Microneedle enclosure and applicator device for microneedle array-based continuous analyte monitoring devices - Patent Application 20070122997

Abstract

To provide a microneedle enclosure and an applicator device for a microneedle array based continuous analyte monitoring device.SOLUTION: An applicator for an analyte monitoring device may include an actuatable housing having a body defining a cavity therein and having a distal opening and a side opening. A cuff and a shuttle are received within the cavity and are separately movable in parallel with the housing body. A base may be removably engaged with the housing body at the distal opening. The housing body, the cuff, the shuttle, and / or the base may be engaged with one another with one or more releasable coupling features. The base may be removed from an engagement with the housing body, causing the cuff and the shuttle to be aligned and positioned in a configuration in which the analyte monitoring device, held by the shuttle, is ready for insertion into the skin.SELECTED DRAWING: Figure 15C

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 249,399, filed September 28, 2021, U.S. Provisional Patent Application No. 63 / 291,293, filed December 17, 2021, and U.S. Provisional Patent Application No. 63 / 355,987, filed June 27, 2022, the contents of which are incorporated herein by reference in their entireties.

[0002] The present invention relates generally to the field of analyte monitoring, such as continuous glucose monitoring. [Background technology]

[0003] Diabetes is a chronic disease in which the body does not produce or properly utilize insulin, a hormone that regulates blood sugar. Insulin can be administered to diabetic patients to help regulate blood sugar levels, but blood sugar levels must nevertheless be carefully monitored to help ensure that timing and dosage are appropriate. Without proper management of their condition, diabetic patients can suffer from a variety of complications resulting from hyperglycemia (high blood sugar levels) or hypoglycemia (low blood sugar levels).

[0004] Blood glucose monitors help diabetic patients manage their condition by measuring blood glucose levels from a sample of blood. For example, a diabetic patient may obtain a blood sample through a finger-prick sampling mechanism, transfer the blood sample to a test strip with a suitable reagent that reacts with the blood sample, and use the blood glucose monitor to analyze the test strip and measure the glucose level in the blood sample. However, patients using this process are typically only able to measure their glucose levels at discrete time points, which may not capture hyperglycemic or hypoglycemic conditions in a timely manner. Another more recent variety of glucose monitor is the continuous glucose monitor (CGM) device, which includes an implantable transcutaneous electrochemical sensor used to continuously detect and quantify blood glucose levels by surrogate measurement of glucose levels in subcutaneous interstitial fluid. However, conventional CGM devices also have weaknesses, including tissue trauma from insertion and signal latency (e.g., due to the time required for the glucose analyte to diffuse from the capillary source to the sensor). These weaknesses also lead to several drawbacks, such as pain experienced by the patient when the electrochemical sensor is inserted and limited accuracy in measuring glucose, especially when blood glucose levels are changing rapidly. Therefore, a need exists for new and improved analyte monitoring systems. Summary of the Invention [Means for solving the problem]

[0005] According to embodiments, the present disclosure relates to analyte monitoring.

[0006] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device comprising: a housing including a body defining a cavity therein, the housing body including a distal opening; a cuff received within the cavity, the cuff including a lumen therethrough; and a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device, the applicator movable between a collapsed configuration, an extended configuration, and a released configuration, wherein in the collapsed configuration the analyte monitoring device is retained within the shuttle and a distal edge of the shuttle and cuff is in a proximal-most position; in the extended configuration the distal edge of the cuff is in a distal-most position and the shuttle is in an intermediate position; and in the released configuration the analyte monitoring device is released from the shuttle and the distal edge of the cuff is in the intermediate position and the shuttle is in the distal-most position.

[0007] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, the housing body comprising a distal opening; a cuff received within the cavity, the cuff comprising a lumen therethrough; and a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device, the applicator being movable between a collapsed configuration, an extended configuration, and a released configuration, wherein in the collapsed configuration, the analyte monitoring device is retained within the shuttle and distal edges of the shuttle and cuff are positioned proximal to the distal opening of the housing body; in the extended configuration, the distal edge of the cuff is positioned distal to the distal opening of the housing body and the shuttle is positioned proximal to the distal opening of the housing body; and in the released configuration, the analyte monitoring device is released from the shuttle and the distal edge of the cuff is positioned distal to the distal opening of the housing body and the shuttle is positioned distal to the distal opening of the housing body.

[0008] In embodiments, the present disclosure further relates to a method of applying an analyte monitoring device to a user's skin surface comprising providing an applicator in a collapsed configuration, the applicator comprising a shuttle that releasably retains the analyte monitoring device, the shuttle being slidably received within a trigger cavity of a cuff, the cuff being received within a cavity of a housing comprising a body defining the cavity, the housing body comprising a distal opening; transitioning the applicator from the collapsed configuration to an extended configuration; and transitioning the applicator from the extended configuration to a released configuration, wherein in the collapsed configuration a distal edge of the shuttle and the cuff are in a proximal-most position; and in the extended configuration the distal edge of the cuff is in a distal-most position and the shuttle is in an intermediate position; and wherein in the released configuration the analyte monitoring device is released from the shuttle, the distal edge of the cuff is in the intermediate position, and the shuttle is in the distal-most position.

[0009] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device comprising: a. a housing comprising a body defining a cavity therein, the housing body comprising a distal opening and a side opening; b. a cuff received within the cavity; c. a shuttle received within the cavity and configured to releasably retain the analyte monitoring device; d. a locking member received at least partially within the side opening of the housing body, the locking member engaged with the cuff in a first configuration and disengaged from the cuff in a second configuration; and e. a base configured to removably couple to the housing body at the distal opening, the base comprising a proximal surface; and f. movement of the locking member from the first configuration to the second configuration releases the cuff, thereby uncoupling the proximal surface from the housing body.

[0010] In embodiments, the present disclosure further relates to a method of using an applicator for an analyte monitoring device, the method including transitioning a locking member of the applicator from a first configuration to a second configuration, the applicator comprising a housing body defining a cavity therein, a cuff and a shuttle each received within the cavity, and a base removably coupled to the housing body, the shuttle releasably retaining the analyte monitoring device, and transitioning the locking member disengaging the locking member from the cuff, thereby allowing the cuff to move relative to the housing body and displacing the base of the applicator relative to the housing body.

[0011] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device comprising: a housing having a body defining a cavity therein; a cuff received within the cavity and having a lumen; and a shuttle received within the lumen, the shuttle comprising: a shaft; and a base portion at a distal end of the shaft, the base portion comprising a plurality of flexible leaves extending from the shaft; and a plurality of petals extending from the shaft, the plurality of flexible leaves defining a receptacle for holding the analyte monitoring device.

[0012] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device comprising: a housing comprising a housing body and a mounting portion; a cuff-ring assembly comprising a cuff and a friction ring coupled to the cuff; and a shuttle configured to releasably retain the analyte monitoring device, wherein the shuttle and the cuff-ring assembly are independently translatable relative to the housing body, and the shuttle and the cuff-ring assembly are each releasably coupled to the mounting portion.

[0013] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device comprising: a housing including a housing body defining a cavity therein and a mounting portion extending from an inner surface of the proximal end of the housing body into the cavity; a cuff having a lumen and a proximal opening; and a cuff-ring assembly including a friction ring positioned within the lumen and extending through the proximal opening, the cuff-ring assembly being positioned around the mounting portion; and a shuttle configured to releasably retain the analyte monitoring device, a portion of which extends through the mounting portion.

[0014] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device, the applicator comprising: a housing including a housing body defining a cavity therein and a mounting portion extending into the cavity; a cuff-ring assembly including a cuff and a friction ring coupled to the cuff; a shuttle configured to releasably retain the analyte monitoring device; and a base removably coupled to the housing, wherein the mounting portion is configured to 1) releasably engage the friction ring to prevent axial movement of the shuttle before removal of the base from the housing, and 2) releasably engage the shuttle to control axial movement of the shuttle after removal of the base from the housing.

[0015] In embodiments, the present disclosure further relates to a method of applying an analyte monitoring device to a skin surface using an applicator, the method including: providing an applicator comprising: a housing defining a cavity, a cuff, and a shuttle, wherein the cuff and shuttle are each received within the cavity, the shuttle retaining the analyte monitoring device; applying a distal surface of the cuff of the applicator to the skin surface; advancing the housing toward the skin surface, wherein advancing the housing moves the housing relative to the cuff and shuttle and disengages one or more retention features that prevent movement of the shuttle independent of the housing, wherein disengagement of the one or more retention features releases the shuttle and advances the shuttle toward the skin surface along with the analyte monitoring device; and releasing the analyte monitoring device from the shuttle.

[0016] In embodiments, the present disclosure further relates to an applicator for an analyte monitoring device, the applicator comprising: a housing having a body defining a cavity therein and a distal opening; a cuff slidably received within the cavity, the cuff having a lumen therethrough; a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device; a first biasing element arranged between the housing and the cuff; a second biasing element arranged between the housing and the shuttle; a microneedle enclosure configured to releasably engage with the analyte monitoring device and, when engaged, to surround a portion of the analyte monitoring device, the microneedle enclosure comprising a third biasing element; and a base releasably engaged with the housing and coupled to the microneedle enclosure. The present invention provides, for example, the following. (Item 1) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, the housing body comprising a distal opening; a cuff received within the cavity, the cuff having a lumen therethrough; a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device; Equipped with the applicator is movable between a collapsed configuration, an extended configuration, and a released configuration; In the collapsed configuration, the analyte monitoring device is retained within the shuttle and a distal edge of the shuttle and the cuff is in a proximal-most position; In the extended configuration, the distal edge of the cuff is in a distal-most position and the shuttle is in an intermediate position; In the released configuration, the analyte monitoring device is released from the shuttle, the distal edge of the cuff is in an intermediate position, and the shuttle is in a distal-most position. Applicator. (Item 2) In the collapsed configuration, a distal edge of the shuttle and the cuff is positioned proximal to a distal opening of the housing body; In the extended configuration, a distal edge of the cuff is positioned distal to a distal opening of the housing body and the shuttle is positioned proximal to the distal opening of the housing body; In the released configuration, a distal edge of the cuff and the shuttle are each positioned distal to a distal opening of the housing body. Item 1. The applicator according to item 1. (Item 3) Item 10. The applicator of item 1, wherein when the applicator is in the collapsed configuration, the position of the distal edge of the cuff is fixed relative to the position of the shuttle. (Item 4) Item 10. The applicator of item 1, further comprising a base configured to removably couple to the housing body at the distal opening. (Item 5) Item 10. The applicator of item 1, further comprising a friction ring releasably engageable with the cuff. (Item 6) Item 5. The applicator of item 4, wherein the housing body further comprises a recess formed in a distal surface of the housing body, and the base further comprises a wall circumferentially disposed around a microneedle enclosure that is releasably coupled to a proximal surface of the base. (Item 7) Item 6. The applicator according to item 5, wherein the housing body further includes a mounting portion extending from the proximal end of the housing body toward the distal opening of the housing body. (Item 8) Item 10. The applicator of item 1, further comprising a locking member at least partially received within at least one side opening of the housing body and releasably engageable with the cuff. (Item 9) Item 10. The applicator of item 1, wherein the applicator is locked when it is in the collapsed configuration. (Item 10) 10. The applicator of claim 9, further comprising a locking member, wherein the applicator is unlocked when the locking member is actuated. (Item 11) Item 9. The applicator of item 8, wherein when the applicator is in the collapsed configuration, the locking member engages with the cuff, thereby preventing the cuff from moving distally toward a distal opening of the housing body. (Item 12) Item 12. The applicator of item 11, wherein engagement between the locking member and the cuff comprises contact between an upper edge of the locking member and a retention edge of the cuff. (Item 13) Item 1, the applicator of item 1, wherein the cuff includes one or more tracks within which one or more corresponding tracking protrusions on the shuttle can slidably engage, thereby maintaining alignment of the cuff and the shuttle, when the applicator is moved from the collapsed configuration to the extended configuration and the released configuration. (Item 14) Item 9. The applicator of item 8, wherein actuation of the locking member releases engagement between the locking member and the cuff, thereby allowing the cuff to move toward a distal opening of the housing body and the applicator to move from the collapsed configuration to the extended configuration. (Item 15) Item 15. The applicator according to item 14, wherein when the locking member is actuated, the shuttle moves toward the distal opening of the housing body. (Item 16) Item 16. The applicator of item 15, further comprising a base configured to removably couple to the housing body at the distal opening, wherein movement of the cuff toward the distal opening of the housing body axially displaces the base relative to the housing body. (Item 17) Item 16. The applicator of item 15, further comprising a base configured to removably couple to the housing body at the distal opening, wherein a distal surface of the cuff presses against a proximal surface of the base during movement of the cuff toward the distal opening of the housing body, thereby displacing the base axially relative to the housing body. (Item 18) Item 18. The applicator of item 17, wherein the distal surface of the cuff is a bottom surface of a bottom flange of the cuff. (Item 19) 7. The applicator of claim 6, wherein the base wall is received within a recess in the housing body when the applicator is in the collapsed configuration. (Item 20) 5. The applicator of claim 4, further comprising a microneedle enclosure releasably coupled to the proximal surface of the base, the microneedle enclosure comprising a cavity and a capsule slidably received therein, the capsule enclosing the microneedle array of the analyte monitoring device when the applicator is in the collapsed configuration. (Item 21) 21. The applicator of claim 20, wherein the microneedle array enclosure maintains the sterility of the microneedle array by the capsule when the applicator is in the collapsed configuration. (Item 22) Item 1, the applicator of claim 1, wherein the housing body further includes a mounting portion extending from the proximal end of the housing body toward the distal opening of the housing body, the mounting portion being releasably engaged with the shuttle when the applicator is in the extended configuration. (Item 23) Item 23. The applicator of item 22, wherein engagement between the mount and the shuttle comprises contact between a retaining surface of at least one downwardly extending finger of the mount and a ledge on an outer surface of the shuttle. (Item 24) Item 5. The applicator of item 4, wherein the base includes a restraining arm configured to be releasably received within a recess in the housing body. (Item 25) Item 25. The applicator of item 24, wherein the restraining arms are biased radially outward toward the housing body when received within a recess in the housing body. (Item 26) Item 25. The applicator of item 24, wherein the restraining arm is configured to prevent reattachment of the base to the housing body when the applicator is in the extended configuration. (Item 27) Item 25. The applicator of item 24, wherein the base further comprises a plurality of restraining arms circumferentially positioned on a proximal surface of the base. (Item 28) Item 5. The applicator of item 4, wherein the base further includes a retaining arm configured to be received between the cuff and an inner surface of the housing body. (Item 29) Item 29. The applicator of item 28, wherein the retention arms are configured to releasably engage retention surfaces on the cuff. (Item 30) 30. The applicator of claim 29, wherein when the applicator is in the extended configuration, the retention arms engage retention surfaces on the cuff, thereby preventing further separation between the base and the cuff. (Item 31) 7. The applicator of claim 6, wherein when the applicator is in the extended configuration, the base wall is outside the recess of the housing body. (Item 32) Item 2. The applicator of item 1, wherein at least a portion of the cuff extends beyond a distal opening of the housing body when the applicator is in the extended configuration. (Item 33) 5. The applicator of claim 4, further comprising a microneedle enclosure releasably coupled to a proximal surface of the base, the microneedle enclosure configured to surround the microneedle array of the analyte monitoring device when the applicator is in the collapsed configuration, and the microneedle enclosure not surrounding the microneedle array when the applicator is in the extended configuration. (Item 34) Item 6. The applicator of item 5, wherein when the applicator is in the extended configuration, the friction ring is engaged with the cuff, thereby preventing the cuff from moving distally relative to the distal opening of the housing body. (Item 35) Item 6. The applicator of item 5, wherein when the applicator is in the extended configuration, a protruding circumferential edge of the friction ring engages with an underside of a step of the cuff, thereby preventing the cuff from moving distally relative to the distal opening of the housing body. (Item 36) Item 6. The applicator of item 5, wherein the friction ring further includes at least one flexible tab extending distally from an upper shoulder of the friction ring, the at least one flexible tab engaging a corresponding lower edge of the cuff adjacent the upper shoulder when the applicator is moved from the collapsed configuration to the extended configuration. (Item 37) Item 37. The applicator of item 36, wherein the friction ring and the cuff are locked together after the applicator is moved to the extended configuration. (Item 38) Item 37. The applicator of item 36, wherein engagement between at least one flexible tab of the friction ring and a corresponding lower edge of the cuff prevents proximal movement of the cuff relative to the friction ring. (Item 39) Item 8. The applicator of item 7, wherein the mounting portion is releasably engaged with the friction ring when the applicator is in the extended configuration. (Item 40) 40. The applicator of claim 39, wherein engagement between the mounting portion and the friction ring comprises contact between a friction ring retaining surface of at least one downwardly extending finger of the mounting portion and a protrusion of the friction ring. (Item 41) 8. The applicator of claim 7, wherein the mounting portion is releasably engaged with the shuttle when the applicator is in the extended configuration. (Item 42) Item 42. The applicator of item 41, wherein engagement between the mounting portion and the shuttle comprises contact between a shuttle retaining surface of at least one downwardly extending finger of the mounting portion and a ledge on an outer surface of the shuttle. (Item 43) Item 42. The applicator of item 41, wherein engagement between the mounting portion and the shuttle prevents the cuff from moving proximally relative to the distal opening of the housing body. (Item 44) Item 5. The applicator of item 4, wherein the applicator is moved from the extended configuration to the released configuration after the base is removed from the housing. (Item 45) Item 41. The applicator of item 40, wherein when the applicator is moved to the release configuration, a friction ring retention surface of at least one downwardly extending finger of the mounting portion disengages from a protrusion of the friction ring. (Item 46) Item 43. The applicator of item 42, wherein when the applicator is moved to the released configuration, a shuttle retention surface of at least one downwardly extending finger of the mounting portion disengages from a ledge on the outer surface of the shuttle. (Item 47) Item 47. The applicator of item 46, wherein when the applicator is moved to the released configuration, disengagement of the friction ring from the mounting portion causes at least one downwardly extending finger of the mounting portion to bend away from the shuttle, thereby releasing a shuttle retention surface of the at least one downwardly extending finger from a shuttle member of the shuttle. (Item 48) Item 48. The applicator of item 47, wherein a biasing member urges the shuttle toward the distal opening of the housing when the shuttle retention surface of the at least one downwardly extending finger releases from the shuttle ledge. (Item 49) Item 10. The applicator of item 1, wherein when the applicator is in the released configuration, a distal end of the shuttle is adjacent to a bottom flange of the cuff. (Item 50) Item 1. The applicator of item 1, wherein when the applicator is in the released configuration, one or more tracking projections on the shuttle engage with a shuttle flex surface of the cuff, thereby preventing further movement of the shuttle relative to the cuff and away from the proximal end of the housing body. (Item 51) Item 8. The applicator of item 7, wherein the applicator comprises a first intermediate configuration between the collapsed configuration and the extended configuration. (Item 52) Item 52. The applicator of item 51, wherein when the applicator is in the first intermediate configuration, the cuff is moved away from the proximal end of the housing body and the shuttle is moved away from the proximal end of the housing body and into engagement with the mounting portion. (Item 53) Item 53. The applicator of item 52, wherein the base is moved away from the proximal end of the housing body and away from the distal opening of the housing body when the cuff is axially displaced. (Item 54) Item 54. The applicator of item 53, wherein the housing body further comprises a recess formed in a distal surface of the housing body, the base further comprises a wall circumferentially disposed on a proximal surface of the base, and removal of the base wall from the recess comprises displacement of the base wall from a corresponding recess in the distal surface of the housing body. (Item 55) Item 5. The applicator of item 4, wherein the applicator is configured to move from the extended configuration to the released configuration following removal of the base from the housing. (Item 56) Item 5. The applicator of item 4, wherein the applicator includes a second intermediate configuration between the extended configuration and the released configuration. (Item 57) Item 57. The applicator of item 56, wherein the base is removed from the housing when the applicator is in the second intermediate configuration. (Item 58) Item 57. The applicator of item 56, wherein the base further comprises a retaining arm configured to be received between the cuff and an inner surface of the housing body, the retaining arm configured to releasably engage a retaining surface on the cuff, and the retaining arm is disengaged from the retaining surface of the cuff when the applicator is in the second intermediate configuration. (Item 59) Item 59. The applicator of item 58, wherein disengagement of the retention arm from the retention surface of the cuff comprises movement of the retention arm over the retention surface and away from the proximal end of the housing body. (Item 60) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, the housing body comprising a distal opening; a cuff received within the cavity, the cuff having a lumen therethrough; a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device; Equipped with the applicator is movable between a collapsed configuration, an extended configuration, and a released configuration; In the collapsed configuration, the analyte monitoring device is retained within the shuttle, and a distal edge of the shuttle and the cuff is positioned proximal to a distal opening of the housing body; In the extended configuration, a distal edge of the cuff is positioned distal to a distal opening of the housing body and the shuttle is positioned proximal to the distal opening of the housing body; In the released configuration, the analyte monitoring device is released from the shuttle, a distal edge of the cuff is positioned distal to a distal opening of the housing body, and the shuttle is positioned distal to the distal opening of the housing body. Applicator. (Item 61) 1. A method of applying an analyte monitoring device to a skin surface of a user, the method comprising: providing an applicator in a collapsed configuration, the applicator including a shuttle that releasably retains an analyte monitoring device, the shuttle being slidably received within a trigger cavity of a cuff, the cuff being received within a cavity of a housing including a body defining the cavity, the housing body including a distal opening; transitioning the applicator from the collapsed configuration to an extended configuration; transitioning the applicator from the extended configuration to a released configuration; Including, In the collapsed configuration, the distal edge of the shuttle and the cuff are in a proximal-most position; In the extended configuration, the distal edge of the cuff is in a distal-most position and the shuttle is in an intermediate position; In the released configuration, the analyte monitoring device is released from the shuttle, the distal edge of the cuff is in an intermediate position, and the shuttle is in a distal-most position. method. (Item 62) Item 62. The method of item 61, wherein transitioning the applicator from the extended configuration to the released configuration includes applying a force to a housing body of the applicator. (Item 63) Item 62. The method of item 61, wherein the applicator further comprises a base configured to removably couple to the housing body at the distal opening. (Item 64) Item 62. The method of item 61, wherein the applicator further comprises a friction ring releasably engageable with the cuff. (Item 65) Item 64. The method of item 63, wherein the housing body further comprises a recess formed in a distal surface of the housing body, and the base further comprises a wall circumferentially disposed around a microneedle enclosure that is releasably coupled to a proximal surface of the base. (Item 66) Item 62. The method of item 61, wherein the housing body further comprises a mounting portion extending from a proximal end of the housing body toward a distal opening of the housing body. (Item 67) The applicator further comprises a locking member at least partially received within at least one side opening of the housing body, and the method further comprises: transitioning the applicator between a locked state and an unlocked state by actuating the locking member through the at least one side opening. Item 62. The method according to Item 61, comprising: (Item 68) When the applicator is in the collapsed configuration, the method further comprises: Engaging the locking member with the cuff, thereby preventing the cuff from moving distally toward the distal opening of the housing body. Item 68. The method according to Item 67, comprising: (Item 69) Item 69. The method of item 68, wherein engagement between the locking member and the cuff comprises contact between an upper edge of the locking member and a retention edge of the cuff. (Item 70) Transitioning from the collapsed configuration to the extended configuration comprises: actuating the locking member to release engagement between the locking member and the cuff, thereby allowing the cuff to move toward the distal opening of the housing body. Item 69. The method according to Item 68, comprising: (Item 71) Item 62. The method of item 61, wherein the housing body further includes a mounting portion extending from a proximal end of the housing body toward a distal opening of the housing body, the mounting portion being releasably engaged with the shuttle when the applicator is in the extended configuration. (Item 72) Transitioning the applicator from the collapsed configuration to the extended configuration comprises: releasing a microneedle enclosure from a portion of the analyte monitoring device, the microneedle enclosure configured to surround a microneedle array of the analyte monitoring device, wherein when the microneedle enclosure is released, the microneedle enclosure does not surround the microneedle array; Item 61. The method according to item 61. (Item 73) Transitioning the applicator from the collapsed configuration to the extended configuration comprises: sliding the cuff relative to the friction ring so that at least one flexible tab extending substantially distally from the upper step of the friction ring engages a corresponding lower edge of the cuff adjacent the upper step; Item 65. The method according to Item 64, comprising: (Item 74) Item 74. The method of item 73, wherein the friction ring and the cuff are locked together in response to transitioning the applicator to the extended configuration. (Item 75) Transitioning the applicator from the extended configuration to the released configuration comprises: Removing the base from the housing. Item 64. The method according to Item 63, comprising: (Item 76) Item 67. The method of item 66, wherein during transition of the applicator from the extended configuration to the released configuration, a friction ring retention surface of at least one downwardly extending finger of the mounting portion disengages from a protrusion of the friction ring. (Item 77) Transitioning the applicator to the released configuration comprises: disengaging a shuttle retaining surface of at least one downwardly extending finger of said mounting portion from a ledge on an exterior surface of said shuttle; Item 67. The method according to Item 66, comprising: (Item 78) Transitioning the applicator to the released configuration comprises: disengaging the friction ring from the mount such that at least one downwardly extending finger of the mount bends away from the shuttle, thereby releasing a shuttle retaining surface of the at least one downwardly extending finger from a shuttle member of the shuttle. Item 67. The method according to Item 66, comprising: (Item 79) Item 67. The method of item 66, further comprising transitioning the applicator to a first intermediate configuration between the collapsed configuration and the extended configuration. (Item 80) 80. The method of claim 79, further comprising moving the cuff away from the proximal end of the housing body and into engagement with the mounting portion. (Item 81) 80. The method of claim 79, further comprising moving the cuff away from the proximal end of the housing, thereby moving the base away from the proximal end of the housing body and the distal opening of the housing body. (Item 82) Transitioning the applicator from the extended configuration to the released configuration comprises: Removing the base from the housing. Item 64. The method according to Item 63, comprising: (Item 83) Item 64. The method of item 63, further comprising transitioning the applicator to a second intermediate configuration between the extended configuration and the released configuration. (Item 84) Item 84. The method of item 83, wherein the base is removed from the housing when the applicator is in the second intermediate configuration. (Item 85) 1. An applicator for an analyte monitoring device, the applicator comprising: a. a housing comprising a body defining a cavity therein, the housing body comprising a distal opening and a side opening; b. a cuff received within the cavity; c. a shuttle received within the cavity and configured to releasably retain the analyte monitoring device; d. a locking member at least partially received within the side opening of the housing body, the locking member engaged with the cuff in a first configuration and disengaged from the cuff in a second configuration; e. a base configured to removably couple to the housing body at the distal opening, the base including a proximal surface; and Equipped with f. movement of the locking member from the first configuration to the second configuration releases the cuff, thereby uncoupling the proximal surface from the housing body; Applicator. (Item 86) Item 86. The applicator of item 85, wherein movement of the locking member from the first configuration to the second configuration allows axial displacement of the cuff relative to the housing body. (Item 87) Item 87. The applicator of item 86, wherein axial displacement of the cuff displaces the base axially relative to the housing body. (Item 88) Item 87. The applicator of item 86, wherein a distal surface of the cuff pushes against a proximal surface of the base during axial displacement of the cuff, thereby separating the proximal surface from the housing body. (Item 89) Item 89. The applicator of item 88, wherein the distal surface of the cuff is a bottom surface of a distal flange of the cuff. (Item 90) Item 86. The applicator of item 85, wherein the base includes a restraining arm configured to be releasably received within a recess in the housing body. (Item 91) Item 91. The applicator of item 90, wherein the restraining arms are biased radially outward or inward toward the housing body when received within a recess in the housing body. (Item 92) Item 91. The applicator of item 90, wherein the restraining arm is configured to prevent reattachment of the base to the housing body after the restraining arm is released from a recess in the housing body. (Item 93) Item 91. The applicator of item 90, wherein the base includes a plurality of restraint arms, the plurality of restraint arms being positioned circumferentially around the proximal surface. (Item 94) Item 86. The applicator of item 85, wherein the base includes a retaining arm configured to be received between the cuff and an inner surface of the housing body. (Item 95) Item 95. The applicator of item 94, wherein the retention arms are configured to releasably engage retention surfaces on the cuff. (Item 96) Item 96. The applicator of item 95, wherein the retention arms prevent separation between the base and the cuff when the retention arms are engaged with retention surfaces on the cuff. (Item 97) Item 96. The applicator of item 95, wherein the retention surface is on an outer surface of the cuff. (Item 98) Item 96. The applicator of item 95, wherein engagement between the retention arms and the retention surfaces of the cuff is maintained during decoupling of the proximal surface from the housing body. (Item 99) Item 95. The applicator of item 94, wherein the base includes a plurality of retention arms, each of the plurality of retention arms configured to be received between the cuff and an inner surface of the housing body. (Item 100) 100. The applicator of claim 99, wherein the plurality of retention arms are positioned circumferentially around the proximal surface. (Item 101) Item 86. The applicator of item 85, wherein the base comprises a retaining arm configured to prevent separation between the base and the housing body, and a restraining arm configured to prevent reattachment of the base to the housing body. (Item 102) Item 92. The applicator of item 91, wherein the length of the restraining arm exceeds the length of the retaining arm. (Item 103) Item 92. The applicator of item 91, wherein the base comprises a plurality of retaining arms and a plurality of restraining arms. (Item 104) Item 86. The applicator of item 85, wherein the base includes a sidewall, an upper edge of the sidewall being received within a recess in the housing body when the locking member is in the first configuration. (Item 105) Item 105. The applicator of item 104, wherein an upper edge of the side wall is outside a recess in the housing body when the locking member is in the second configuration. (Item 106) Item 86. The applicator of item 85, wherein the cuff includes a retention edge, and the locking member is engaged with the retention edge in the first configuration and disengaged from the retention edge in the second configuration. (Item 107) Item 86. The applicator of item 85, wherein the locking member is configured to transition from the first configuration to the second configuration in response to depression of a portion of the locking member. (Item 108) Item 108. The applicator of item 107, wherein the locking member is configured to pivot in response to depression of a portion of the locking member. (Item 109) Item 108. The applicator of item 107, wherein the housing body includes a flexible contact member configured to limit movement of the locking member. (Item 110) Item 109. The applicator of item 109, wherein a first end of the flexible contact member is coupled to the housing body and a second end is coupled to the locking member. (Item 111) Item 86. The applicator of item 85, wherein the cuff includes a lumen and the shuttle is positioned within the lumen. (Item 112) Item 112. The applicator of item 111, wherein the shuttle is configured to move axially within the lumen of the cuff. (Item 113) Item 86. The applicator of item 85, wherein the base is configured to preserve sterility of the analyte monitoring device when the locking member is in the first configuration. (Item 114) Item 86. The applicator of item 85, wherein the housing includes a guide member configured to maintain axial and rotational alignment between the housing body and the cuff. (Item 115) Item 86. The applicator of item 85, further comprising: a first biasing element arranged between the housing body and the cuff; and a second biasing element arranged between the housing body and the shuttle. (Item 116) Item 117. A method of using an applicator for an analyte monitoring device, the method including transitioning a locking member of the applicator from a first configuration to a second configuration, the applicator comprising a housing body defining a cavity therein, a cuff and a shuttle each received within the cavity, and a base removably coupled to the housing body, the shuttle releasably retaining the analyte monitoring device, and transitioning the locking member disengaging the locking member from the cuff, thereby allowing the cuff to move relative to the housing body and displacing a base of the applicator relative to the housing body. 1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein; a cuff received within the cavity and having a lumen; a shuttle received within the lumen, the shuttle comprising: A shaft, a base portion at a distal end of the shaft, the base portion comprising a plurality of flexible leaves extending from the shaft and a plurality of petals extending from the shaft, the plurality of flexible leaves defining a receptacle for retaining the analyte monitoring device; Equipped with a shuttle An applicator comprising: (Item 118) Item 118. The applicator of item 117, wherein at least one flexible leaf of the plurality of flexible leaves comprises an arcuate member. (Item 119) Item 119. The applicator of item 118, wherein at least one flexible leaf of the plurality of flexible leaves further comprises a flexible connector coupling the arcuate member to the core. (Item 120) Item 119. The applicator of item 118, wherein the arcuate member comprises a support surface configured to engage the analyte monitoring device when the analyte monitoring device is received within the receptacle. (Item 121) Item 121. The applicator of item 120, wherein the support surface extends inwardly at a distal end of the arcuate member. (Item 122) Item 118. The applicator of item 117, wherein each flexible leaf of the plurality of flexible leaves is configured to flex radially outward. (Item 123) Item 123. The applicator of item 122, wherein each flexible leaf of the plurality of flexible leaves is configured to move relative to the shaft. (Item 124) Item 118. The applicator of item 117, wherein the plurality of flexible leaves are arranged circumferentially about the shaft. (Item 125) Item 118. The applicator of item 117, wherein a distal surface of at least one support petal of the plurality of support petals comprises a radiused surface. (Item 126) Item 126. The applicator of item 125, wherein the at least one support petal further comprises a flexible connector connecting the radiused surface to the shaft. (Item 127) Item 126. The applicator of item 125, wherein the free end of the radiused surface comprises a support grip configured to engage the analyte monitoring device when the analyte monitoring device is retained within the receptacle. (Item 128) Item 128. The applicator of item 127, wherein the support gripper is configured to engage a proximal surface of the analyte monitoring device when the analyte monitoring device is retained within the receptacle. (Item 129) Item 118. The applicator of item 117, wherein the plurality of support petals are configured to stabilize the analyte monitoring device when the analyte monitoring device is retained within the receptacle. (Item 130) Item 118. The applicator of item 117, wherein the plurality of flexible leaves and the plurality of petals are arranged in an alternating configuration around the shaft. (Item 131) Item 118. The applicator of item 117, wherein at least one flexible leaf of the plurality of flexible leaves includes a following projection extending radially outward from an outer surface of the at least one flexible leaf. (Item 132) Item 132. The applicator of item 131, wherein the tracking projection is configured to engage a surface of the cuff and stop axial movement of the shuttle. (Item 133) Item 118. The applicator of item 117, wherein the shaft comprises an internal cavity. (Item 134) Item 134. The applicator of item 133, further comprising a biasing element positioned within the inner cavity. (Item 135) Item 135. The applicator of item 134, wherein the biasing element is configured to transfer stored energy to the shuttle to displace each leaf of the plurality of flexible leaves radially outward. (Item 136) Item 136. The applicator of item 135, wherein radially outward displacement of each leaf of the plurality of flexible leaves is configured to release the analyte monitoring device from the receptacle when retained therein. (Item 137) Item 118. The applicator of item 117, wherein the shuttle is configured to prevent reinsertion of the analyte monitoring device into the receptacle after being released therefrom. (Item 138) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing including a housing main body and a mounting portion; a cuff-ring assembly including a cuff and a friction ring coupled to the cuff; a shuttle configured to releasably retain the analyte monitoring device; Equipped with the shuttle and the cuff ring assembly are independently translatable relative to the housing body, and the shuttle and the cuff ring assembly are each releasably coupled to the mounting portion; Applicator. (Item 139) Item 139. The applicator of item 138, wherein the mounting portion comprises a plurality of fingers extending from an inner surface of the proximal end of the housing body into the cavity. (Item 140) Item 140. The applicator of item 139, wherein the plurality of fingers define a rounded footprint. (Item 141) Item 140. The applicator of item 139, wherein at least one finger of the plurality of fingers includes a ring retention surface releasably coupled to the friction ring. (Item 142) Item 142. The applicator of item 141, wherein the friction ring comprises a ring core and a protrusion extending inward from an inner surface of the ring core, the ring retention surface being releasably coupled to the protrusion. (Item 143) Item 142. The applicator of item 141, wherein the ring retention surface comprises a step formed on an outward facing surface of at least one of the plurality of fingers of the mounting portion. (Item 144) Item 140. The applicator of item 139, wherein at least one finger of the plurality of fingers comprises a shuttle retaining surface that is releasably engaged with the shuttle. (Item 145) Item 145. The applicator of item 144, wherein the shuttle includes an angled surface, and the shuttle retaining surface releasably engages the angled surface. (Item 146) Item 145. The applicator of item 144, wherein the shuttle retaining surface comprises a shoulder formed along an inwardly facing surface of at least one of the plurality of fingers. (Item 147) Item 147. The applicator of item 146, wherein the shuttle comprises a shaft including a ledge having a distal angled surface, the shoulder releasably engaging the distal angled surface. (Item 148) Item 140. The applicator of claim 139, wherein at least one finger of the plurality of fingers comprises a ring retention surface releasably coupled to the friction ring and a shuttle retention surface releasably engaged with a distal angled surface on the outer surface of the shuttle shaft. (Item 149) Item 149. The applicator of item 148, wherein the ring retaining surface is on an outward facing surface of at least one finger of the plurality of fingers, and the shuttle retaining surface is on an inward facing surface of a finger of the plurality of fingers. (Item 150) Item 149. The applicator of item 148, wherein the ring retention surface and the friction ring are configured to decouple during actuation of the housing. (Item 151) Item 149. The applicator of item 148, wherein the shuttle retaining surface and the distal angled surface of the shuttle shaft are configured to disengage during actuation of the housing. (Item 152) Item 149. The applicator of item 148, wherein during actuation of the housing, the ring retention surface is configured to disengage from the friction ring before the shuttle retention surface is configured to disengage from the angled surface of the shuttle shaft. (Item 153) Item 153. The applicator of item 152, wherein the shuttle is configured to move axially toward the distal end of the housing body after disengagement of the shuttle retention surface and the distal angled surface of the shuttle shaft. (Item 154) Item 154. The applicator of item 153, wherein the shuttle shaft further comprises a proximal angled surface, and wherein a distal end of the shuttle retaining surface engages the proximal angled surface of the shuttle shaft after disengagement of the shuttle retaining surface and the distal angled surface of the shuttle shaft in response to axial movement of the shuttle toward the proximal end of the housing. (Item 155) Item 155. The applicator of item 154, wherein the distal end of the shuttle retaining surface comprises a flat surface. (Item 156) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing including a housing body defining a cavity therein and a mounting portion extending from an interior surface of a proximal end of the housing body into the cavity; a cuff ring assembly including a cuff having a lumen and a proximal opening, and a friction ring positioned within the lumen and extending through the proximal opening, the cuff ring assembly being positioned around the mounting portion; a shuttle configured to releasably retain the analyte monitoring device, a portion of which extends through the mounting portion; and An applicator comprising: (Item 157) Item 157. The applicator of item 156, wherein the mounting portion comprises a plurality of fingers extending from an inner surface of the proximal end of the housing body into the cavity. (Item 158) Item 158. The applicator of item 157, wherein the plurality of fingers define a rounded footprint. (Item 159) Item 158. The applicator of item 157, wherein at least one finger of the plurality of fingers includes a ring retention surface releasably coupled to the friction ring. (Item 160) Item 159. The applicator of item 159, wherein the friction ring comprises a ring core and a protrusion extending inward from an inner surface of the ring core, the ring retention surface being releasably coupled to the protrusion. (Item 161) Item 159. An applicator as described in item 159, wherein the ring retention surface comprises a step formed on an outward facing surface of at least one of the plurality of fingers of the mounting portion. (Item 162) Item 158. The applicator of item 157, wherein at least one finger of the plurality of fingers includes a shuttle retaining surface that is releasably engaged with the shuttle. (Item 163) Item 163. The applicator of item 162, wherein the shuttle comprises an angled surface, and the shuttle retaining surface releasably engages the angled surface. (Item 164) Item 164. The applicator of item 163, wherein the shuttle retaining surface comprises a shoulder formed along an inwardly facing surface of at least one of the plurality of fingers. (Item 165) Item 165. The applicator of item 164, wherein the shuttle comprises a shaft comprising a ledge having a distal angled surface, the shoulder releasably engaging the distal angled surface. (Item 166) Item 158. The applicator of item 157, wherein at least one finger of the plurality of fingers comprises a ring retaining surface that is releasably coupled to the friction ring and a shuttle retaining surface that is releasably coupled to an angled surface on the shuttle shaft. (Item 167) Item 167. The applicator of item 166, wherein the ring retaining surface is on an outward facing surface of at least one finger of the plurality of fingers, and the shuttle retaining surface is on an inward facing surface of a finger of the plurality of fingers. (Item 168) Item 168. The applicator of item 167, wherein the ring retention surface and the friction ring are configured to decouple during actuation of the housing. (Item 169) Item 168. The applicator of item 167, wherein the shuttle retaining surface and the shuttle are configured to engage and disengage during actuation of the housing. (Item 170) Item 168. The applicator of item 167, wherein during actuation of the housing, the ring retention surface is configured to disengage from the friction ring before the shuttle retention surface is configured to disengage from the shuttle. (Item 171) Item 171. The applicator of item 170, wherein the shuttle is configured to move axially toward the distal end of the housing body after disengagement of the shuttle retaining surface and the shuttle. (Item 172) Item 172. The applicator of item 171, wherein the shuttle comprises a shaft including a proximal angled surface and a distal angled surface, and wherein a distal end of the shuttle retaining surface engages with the proximal angled surface of the shuttle shaft after disengagement of the shuttle retaining surface and the distal angled surface of the shuttle shaft in response to axial movement of the shuttle toward the proximal end of the housing. (Item 173) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing including a housing body defining a cavity therein and a mounting portion extending into the cavity; a cuff-ring assembly including a cuff and a friction ring coupled to the cuff; a shuttle configured to releasably retain the analyte monitoring device; a base removably coupled to the housing; Equipped with The mount is configured to 1) releasably engage the friction ring to prevent axial movement of the shuttle prior to removal of the base from the housing, and 2) releasably engage the shuttle to control axial movement of the shuttle after removal of the base from the housing. Applicator. (Item 174) Item 174. The applicator of item 173, wherein the mounting portion comprises a first retaining feature that is releasably engaged with the friction ring and prevents axial movement of the shuttle before removal of the base from the housing, and a second retaining feature that is releasably engaged with the shuttle and controls axial movement of the shuttle after removal of the base from the housing. (Item 175) Item 175. The applicator of item 174, wherein the first retaining feature is on a first side of the mounting portion and the second retaining feature is on a second, opposing side of the mounting portion. (Item 176) 1. A method of applying an analyte monitoring device to a skin surface using an applicator, the method comprising: providing an applicator comprising a housing defining a cavity, a cuff, and a shuttle, the cuff and the shuttle each being received within the cavity, the shuttle retaining the analyte monitoring device; applying a distal surface of the applicator cuff to the skin surface; advancing the housing toward the skin surface, where advancing the housing moves the housing relative to the cuff and the shuttle and disengages one or more retention features that prevent movement of the shuttle independent of the housing, where disengagement of the one or more retention features releases the shuttle and advances the shuttle along with the analyte monitoring device toward the skin surface; Releasing the analyte monitoring device from the shuttle; A method comprising: (Item 177) 177. The method of claim 176, wherein releasing the analyte monitoring device from the shuttle comprises engaging a tracking protrusion on the shuttle with a flexible surface on the cuff. (Item 178) Item 178. The method of item 177, wherein the shuttle comprises a plurality of flexible leaves, and wherein engaging the following projections of the shuttle with the flexing surfaces of the cuff flexes the flexible leaves radially outward. (Item 179) 177. The method of claim 176, wherein advancing the housing toward the skin surface comprises piercing the skin surface with a microneedle array of the analyte monitoring device. (Item 180) 180. The method of claim 179, wherein advancing the housing toward the skin surface comprises adhering the analyte monitoring device to the skin surface. (Item 181) Item 177. The method of item 176, further comprising removing the base of the applicator from the housing prior to applying the distal surface of the cuff to the skin surface. (Item 182) 182. The method of claim 181, wherein removing the base from the applicator further comprises breaking a sterile seal around a microneedle array of the analyte monitoring device. (Item 183) Item 177. The method of item 176, further comprising transitioning a locking member of the applicator from a first configuration to a second configuration. (Item 184) Item 184. The method of item 183, wherein transitioning the locking member disengages the locking member from the cuff, thereby allowing the cuff to move relative to the housing. (Item 185) Item 185. The method of item 184, wherein movement of the cuff relative to the housing in response to engagement and disengagement of the locking member from the cuff causes a base of the applicator to move relative to the housing. (Item 186) Item 186. The method of claim 185, wherein movement of the base relative to the housing breaks a sterile seal between a microneedle enclosure coupled to the base and the analyte monitoring device. (Item 187) Item 186. The method of item 185, further comprising removing the base from the applicator. (Item 188) 1. An applicator for an analyte monitoring device, the applicator comprising: a housing having a body defining a cavity therein and a distal opening; a cuff slidably received within the cavity, the cuff having a lumen therethrough; a shuttle slidably received within the lumen and configured to releasably retain the analyte monitoring device; a first biasing element disposed between the housing and the cuff; a second biasing element disposed between the housing and the shuttle; a microneedle enclosure configured to releasably engage the analyte monitoring device and, when engaged, to enclose a portion of the analyte monitoring device, the microneedle enclosure comprising a third biasing element; and a base releasably engaged with the housing and coupled to the microneedle enclosure; An applicator comprising: (Item 189) Item 189. The applicator of item 188, wherein the first biasing element is configured to bias the cuff toward the distal opening. (Item 190) Item 189. The applicator of item 188, wherein the second biasing element is configured to bias the shuttle toward the distal opening. (Item 191) Item 189. The applicator of item 188, wherein the microneedle enclosure, when engaged, maintains the sterility of the analyte monitoring device. (Item 192) Item 189. The applicator of item 188, wherein the shuttle is configured to slide relative to the cuff and the housing body. (Item 193) Item 189. The applicator of item 188, wherein the cuff is configured to slide relative to the shuttle and the housing body. (Item 194) Item 189. The applicator of item 188, wherein the microneedle enclosure comprises a cavity and a capsule slidably received therein, the cavity comprising the third biasing element, and the capsule enclosing a portion of the analyte monitoring device when the microneedle enclosure and the analyte monitoring device are engaged. (Item 195) Item 195. The applicator of item 194, wherein the third biasing element biases the capsule toward the analyte monitoring device. (Item 196) The microneedle enclosure further comprises: a force collector arranged within the cavity, the force collector including a shaft and a head, the shaft being disposed within the third biasing element; the force collector and the third biasing element are adapted to bias the capsule toward the analyte monitoring device and maintain the enclosure for the analyte monitoring device; Item 195. The applicator of item 194. (Item 197) Item 189. The applicator of item 188, wherein the shuttle and the cuff are telescopically arranged within the housing body. (Item 198) Item 189. The applicator of item 188, wherein the first biasing element, the second biasing element, and the third biasing element are each selected from the group consisting of a coiled metal spring, a plastic leaf spring, and a coiled plastic spring. (Item 199) Item 189. The applicator of item 188, wherein the analyte monitoring device comprises a microneedle array oriented away from the proximal end of the housing body. (Item 200) Item 189. The applicator of item 188, wherein the first biasing element is further arranged around a mounting portion extending from a proximal end of the housing body toward a distal opening of the housing body. (Item 201) Item 201. The applicator of item 200, wherein the mounting portion comprises at least one downwardly extending finger configured to releasably engage the shuttle. (Item 202) Item 201. The applicator of item 200, further comprising a friction ring arranged around the mounting portion and around the shuttle shaft, the shuttle shaft extending toward the proximal end of the housing body, away from the analyte monitoring device. (Item 203) Item 203. The applicator of item 202, wherein the mounting portion includes at least one downwardly extending finger configured to releasably engage the friction ring. (Item 204) Item 203. The applicator of item 202, further comprising a locking member at least partially received within the side opening of the housing body and releasably engaged with the cuff. (Item 205) Item 205. The applicator of item 204, wherein actuation of the locking member releases engagement between the locking member and the cuff, thereby allowing the cuff to move. (Item 206) Item 189. The applicator of item 188, wherein the microneedle enclosure comprises a locking tab configured to engage a connector feature of the analyte monitoring device. (Item 207) Item 189. The applicator of item 188, wherein the base includes a retaining arm configured to be received between the cuff and an inner surface of the housing body. (Item 208) Item 208. The applicator of item 207, wherein the retention arms are configured to releasably engage retention surfaces on the cuff. (Item 209) Item 209. The applicator of item 208, wherein the retention arms prevent separation between the base and the cuff when the retention arms are engaged with retention surfaces on the cuff. (Item 210) Item 208. The applicator of item 207, wherein the base includes a plurality of retention arms, each of the plurality of retention arms configured to be received between the cuff and an inner surface of the housing body. (Item 211) Item 189. The applicator of item 188, wherein the base includes a restraining arm configured to be releasably received within a recess in the housing body. (Item 212) Item 212. The applicator of item 211, wherein the restraining arms are biased radially outward toward the housing body when received within recesses in the housing body. (Item 213) Item 212. The applicator of item 211, wherein the base includes a plurality of restraint arms, the plurality of restraint arms being positioned circumferentially around the base. (Item 214) Item 189. The applicator of item 188, wherein the cuff includes one or more tracks in which corresponding one or more following protrusions on the shuttle can be slidably engaged. (Item 215) Item 215. The applicator of item 214, wherein the one or more tracks are circumferentially arranged around the cuff and the corresponding one or more following protrusions are circumferentially arranged at corresponding locations around the shuttle. (Item 216) Item 189. An applicator as described in Item 188, wherein the housing body has one or more guides on its inner surface and the cuff has one or more corresponding guide protrusions on its outer surface, the one or more corresponding guide protrusions being slidably engageable with the one or more guides. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 depicts an illustrative schematic of an analyte monitoring system involving a microneedle array.

[0018] [Figure 2A] FIG. 2A depicts an illustrative schematic diagram of an analyte monitoring device.

[0019] [Figure 2B] FIG. 2B depicts an illustrative schematic of microneedle insertion depth in an analyte monitoring device.

[0020] [Figure 3] 3A-3D depict a top side perspective view, a side view, a bottom view, and an exploded view, respectively, of an analyte monitoring device.

[0021] [Figure 4-1] 4A-4E depict an exploded perspective view, an exploded side view, a bottom perspective view, a side view, and a top side perspective view, respectively, of a sensor assembly within an analyte monitoring device.

[0022] [Figure 4-2] 4F-4H depict a perspective exploded view, a side exploded view, and a side view, respectively, of a sensor assembly within an analyte monitoring device.

[0023] [Figure 5-1] 5A-5D depict a side view of the microneedle enclosure in an exploded view, a first side and side cross-sectional view, a second side and side cross-sectional view, and a bottom perspective view, respectively.

[0024] [Figure 5-2]5E-5G depict a side view of the microneedle enclosure with the base plate of the analyte monitoring device in a perspective exploded view, a perspective view, and a side cross-sectional view, respectively.

[0025] [Figure 6] Figure 6A depicts an illustrative schematic diagram of a microneedle array. Figure 6B depicts an illustrative schematic diagram of a microneedle within the microneedle array depicted in Figure 6A.

[0026] [Figure 7] FIG. 7 depicts an illustrative schematic of a microneedle array used for sensing multiple analytes.

[0027] [Figure 8] Figure 8A depicts a cross-sectional side view of a pillar-shaped microneedle having a tapered distal end. Figures 8B and 8C are images depicting a perspective and detailed view, respectively, of the microneedle embodiment shown in Figure 8A.

[0028] [Figure 9] FIG. 9 depicts an illustrative schematic of a pillar-shaped microneedle with a tapered distal end.

[0029] [Figure 10-1] Figures 10A and 10B depict illustrative schematic diagrams of a microneedle array and microneedles, respectively. Figures 10C-10F depict detailed partial views of illustrative variations of microneedles. [Figure 10-2] Figures 10A and 10B depict illustrative schematic diagrams of a microneedle array and microneedles, respectively. Figures 10C-10F depict detailed partial views of illustrative variations of microneedles.

[0030] [Figure 11] 11A and 11B depict illustrative variations of microneedles.

[0031] [Figure 12-1]12A and 12B depict illustrative schematic diagrams of microneedle array configurations. Figures 12C and 12D depict illustrative schematic diagrams of microneedle array configurations. [Figure 12-2] 12A and 12B depict illustrative schematic diagrams of microneedle array configurations. Figures 12C and 12D depict illustrative schematic diagrams of microneedle array configurations.

[0032] [Figure 13] 13A and 13B depict perspective and orthogonal views, respectively, of an illustrative variation of a die containing a microneedle array.

[0033] [Figure 14A] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14B] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14C] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14D] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14E] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14F] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14G] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14H] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14I] 14A-14J depict illustrative schematics of different variations of microneedle array configurations. [Figure 14J] 14A-14J depict illustrative schematics of different variations of microneedle array configurations.

[0034] [Figure 15A] 15A-15D depict a side view of an applicator for an analyte monitoring device in a first side view, a second side view, a top perspective view, and a bottom perspective view, respectively. [Figure 15B] 15A-15D depict a side view of an applicator for an analyte monitoring device in a first side view, a second side view, a top perspective view, and a bottom perspective view, respectively. [Figure 15C] 15A-15D depict a side view of an applicator for an analyte monitoring device in a first side view, a second side view, a top perspective view, and a bottom perspective view, respectively. [Figure 15D] 15A-15D depict a side view of an applicator for an analyte monitoring device in a first side view, a second side view, a top perspective view, and a bottom perspective view, respectively.

[0035] [Figure 15E] 15E and 15F depict the side of the analyte monitoring device relative to the shuttle of the applicator in exploded and perspective views, respectively. [Figure 15F] 15E and 15F depict the side of the analyte monitoring device relative to the shuttle of the applicator in exploded and perspective views, respectively.

[0036] [Figure 16-1] 16A-16D depict a side view of a shuttle of an applicator for an analyte monitoring device in a top perspective view, a bottom view, a side view, and a side cross-sectional view, respectively. [Figure 16-2] 16A-16D depict a side view of a shuttle of an applicator for an analyte monitoring device in a top perspective view, a bottom view, a side view, and a side cross-sectional view, respectively.

[0037] [Figure 16-3] 16E and 16F depict a side view of an applicator shuttle for an analyte monitoring device in bottom perspective and plan views, respectively.

[0038] [Figure 16-4] 16G and 16H depict a side view of a shuttle of an applicator for an analyte monitoring device in a side view and a side cross-sectional view, respectively.

[0039] [Figure 17-1] 17A-17E depict a side view of an applicator cuff for an analyte monitoring device in a top perspective view, a bottom view, a top view, a first side and cross-sectional side view, and a second side and cross-sectional side view, respectively. [Figure 17-2] 17A-17E depict a side view of an applicator cuff for an analyte monitoring device in a top perspective view, a bottom view, a top view, a first side and cross-sectional side view, and a second side and cross-sectional side view, respectively.

[0040] [Figure 17-3] 17F and 17G depict the side of an applicator cuff for an analyte monitoring device in bottom and side views, respectively.

[0041] [Figure 18-1] 18A-18D depict a side view of a locking friction ring of an applicator for an analyte monitoring device in a first top perspective view, a second top perspective view, a first bottom perspective view, and a second bottom perspective view, respectively. [Figure 18-2] 18A-18D depict a side view of a locking friction ring of an applicator for an analyte monitoring device in a first top perspective view, a second top perspective view, a first bottom perspective view, and a second bottom perspective view, respectively.

[0042] [Figure 19-1] 19A-19E depict a side view of a cuff-ring assembly of an applicator for an analyte monitoring device in top perspective, bottom, top, side, and side cross-sectional views, respectively, along with a detailed view. [Figure 19-2]19A-19E depict a side view of a cuff-ring assembly of an applicator for an analyte monitoring device in top perspective, bottom, top, side, and side cross-sectional views, respectively, along with a detailed view.

[0043] [Figure 20-1] 20A-20F depict a side view of an applicator housing for an analyte monitoring device in a first top perspective view, a second top perspective view, a first bottom perspective view, a second bottom perspective view, a first cross-sectional side view, and a second cross-sectional side view, respectively. [Figure 20-2] 20A-20F depict a side view of an applicator housing for an analyte monitoring device in a first top perspective view, a second top perspective view, a first bottom perspective view, a second bottom perspective view, a first cross-sectional side view, and a second cross-sectional side view, respectively.

[0044] [Figure 21] 21A-21B depict a side view of a locking member of an applicator for an analyte monitoring device in front and back perspective views, respectively.

[0045] [Figure 22A] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22B] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22C] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22D]22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22E] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22F] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively. [Figure 22G] 22A-22G depict the side of a base of an applicator for an analyte monitoring device in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view, respectively.

[0046] [Figure 22H] 22H-22J depict a side view of the base of an applicator for an analyte monitoring device with a microneedle enclosure in exploded, top perspective, and side cross-sectional views, respectively. [Figure 22I] 22H-22J depict a side view of the base of an applicator for an analyte monitoring device with a microneedle enclosure in exploded, top perspective, and side cross-sectional views, respectively. [Figure 22J] 22H-22J depict a side view of the base of an applicator for an analyte monitoring device with a microneedle enclosure in exploded, top perspective, and side cross-sectional views, respectively.

[0047] [Figure 22K] FIG. 22K depicts, in a top perspective view, a side view of the base of an applicator for an analyte monitoring device engaged with the cuff of the applicator.

[0048] [Figure 23-1] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-2] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-3] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-4] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-5] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-6] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations. [Figure 23-7] 23A-23O depict, in cross section and close-up, diagrams of applicators for analyte monitoring devices in various configurations.

[0049] [Figure 24] FIG. 24 is a process flow chart illustrating the process of the applicator from the collapsed configuration to the extended configuration.

[0050] [Figure 25] FIG. 25 is a process flow chart illustrating the process of the applicator from the extended configuration to the released configuration.

[0051] [Figure 26] 26A and 26B depict, in cross section and close-up, views of an applicator for an analyte monitoring device in various configurations.

[0052] [Figure 27-1] Figures 27A-27C depict top side perspective, side, and bottom perspective views, respectively, of an analyte monitoring device. Figure 27D depicts a partially exploded view of the analyte monitoring device shown in Figure 27A, including the adhesive layer. Figure 27E depicts an exploded view of the analyte monitoring device shown in Figure 27A. [Figure 27-2] Figures 27A-27C depict top side perspective, side, and bottom perspective views, respectively, of an analyte monitoring device. Figure 27D depicts a partially exploded view of the analyte monitoring device shown in Figure 27A, including the adhesive layer. Figure 27E depicts an exploded view of the analyte monitoring device shown in Figure 27A. [Figure 27-3] Figures 27A-27C depict top side perspective, side, and bottom perspective views, respectively, of an analyte monitoring device. Figure 27D depicts a partially exploded view of the analyte monitoring device shown in Figure 27A, including the adhesive layer. Figure 27E depicts an exploded view of the analyte monitoring device shown in Figure 27A.

[0053] [Figure 27-4] 27F-27I depict a top perspective view, a bottom perspective view, a side view, and an exploded view, respectively, of a sensor assembly in an analyte monitoring device.

[0054] [Figure 27-5] FIG. 27J depicts a transparent side view of a sensor assembly in an analyte monitoring device.

[0055] [Figure 28-1] 28A-28E depict a perspective view, a side view, a bottom view, a side cross-sectional view, and a top perspective transparent view, respectively, of an analyte monitoring device. [Figure 28-2] 28A-28E depict a perspective view, a side view, a bottom view, a side cross-sectional view, and a top perspective transparent view, respectively, of an analyte monitoring device.

[0056] [Figure 29]FIG. 29 depicts a cross-sectional side view of a pillar-shaped microneedle with a tapered distal end.

[0057] [Figure 30] FIG. 30 depicts an illustrative schematic of a pillar-shaped microneedle with a tapered distal end.

[0058] [Figure 31] Figures 31A-31C depict a top side perspective view, a side view, and a bottom perspective view of the applicator, respectively. Figure 31D depicts an exploded view of the applicator shown in Figures 31A-31C.

[0059] [Figure 32-1] 32A-32G depict a top side perspective view, a bottom perspective view, another top side perspective view, another bottom perspective view, a top view, a side view, and a bottom view, respectively, of the shuttle of the applicator. [Figure 32-2] 32A-32G depict a top side perspective view, a bottom perspective view, another top side perspective view, another bottom perspective view, a top view, a side view, and a bottom view, respectively, of the shuttle of the applicator.

[0060] [Figure 33-1] Figures 33A-33E depict a top side perspective view, a top view, a bottom view, a bottom perspective view, and a side view, respectively, of the applicator's trigger. Figure 33F depicts another side view of the trigger shown in Figures 33A-33E, and Figure 33G depicts a cross-sectional view of the trigger taken along line 18G:18G shown in Figure 33F. [Figure 33-2] Figures 33A-33E depict a top side perspective view, a top view, a bottom view, a bottom perspective view, and a side view, respectively, of the applicator's trigger. Figure 33F depicts another side view of the trigger shown in Figures 33A-33E, and Figure 33G depicts a cross-sectional view of the trigger taken along line 18G:18G shown in Figure 33F.

[0061] [Figure 34-1]Figure 34A depicts a top side perspective view of the housing of the applicator. Figures 34B-34F depict top side perspective, top, bottom, bottom perspective, and side views, respectively, of the housing shown in Figure 34A. Figure 34G depicts a side cross-sectional view of the housing taken along line 19G:19G shown in Figure 34F. [Figure 34-2] Figure 34A depicts a top side perspective view of the housing of the applicator. Figures 34B-34F depict top side perspective, top, bottom, bottom perspective, and side views, respectively, of the housing shown in Figure 34A. Figure 34G depicts a side cross-sectional view of the housing taken along line 19G:19G shown in Figure 34F.

[0062] [Figure 34-3] 34H and 34I depict exemplary variations of the applicator housing.

[0063] [Figure 35] Figure 35A depicts a bottom view of the applicator at the beginning of a loading process for loading an analyte monitoring device into the applicator, and Figure 35B depicts a bottom view of the applicator of Figure 35A after an analyte monitoring device has been loaded into the applicator.

[0064] [Figure 36A] 36A-36C depict the loading process for loading an analyte monitoring device into an applicator. [Figure 36B] 36A-36C depict the loading process for loading an analyte monitoring device into an applicator. [Figure 36C] 36A-36C depict the loading process for loading an analyte monitoring device into an applicator.

[0065] [Figure 37A]Figures 37A, 37B, and 37D depict cross-sectional views of an applicator in a primed configuration for deploying an analyte monitoring device from the applicator. Figure 37C depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle C in Figure 37B. Figure 37E depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle D in Figure 37D. [Figure 37B] Figures 37A, 37B, and 37D depict cross-sectional views of an applicator in a primed configuration for deploying an analyte monitoring device from the applicator. Figure 37C depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle C in Figure 37B. Figure 37E depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle D in Figure 37D. [Figure 37C] Figures 37A, 37B, and 37D depict cross-sectional views of an applicator in a primed configuration for deploying an analyte monitoring device from the applicator. Figure 37C depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle C in Figure 37B. Figure 37E depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle D in Figure 37D. [Figure 37D] Figures 37A, 37B, and 37D depict cross-sectional views of an applicator in a primed configuration for deploying an analyte monitoring device from the applicator. Figure 37C depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle C in Figure 37B. Figure 37E depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle D in Figure 37D. [Figure 37E] Figures 37A, 37B, and 37D depict cross-sectional views of an applicator in a primed configuration for deploying an analyte monitoring device from the applicator. Figure 37C depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle C in Figure 37B. Figure 37E depicts a detailed cross-sectional view of a portion of the primed applicator indicated by circle D in Figure 37D.

[0066] [Figure 38] FIG. 38 depicts a cross-sectional view of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator.

[0067] [Figure 39] Figures 39A-39C depict a top side perspective view, a side view, and a bottom perspective view of the applicator, respectively. Figure 39D depicts an exploded view of the applicator shown in Figures 39A-39C.

[0068] [Figure 40] 40A and 40B depict a top side perspective view and a top view, respectively, of the shuttle of the applicator.

[0069] [Figure 41] Figures 41A-41D depict upper side perspective, top, lower perspective, and side views, respectively, of the applicator's trigger, and Figure 41E depicts a cross-sectional view of the trigger taken along line 26E:26E shown in Figure 41D.

[0070] [Figure 42] Figures 42A-42C depict a top side perspective view, a top view, and a side view, respectively, of the housing of the applicator. Figure 42D depicts a cross-sectional view of the housing taken along line 27D:27D shown in Figure 42C. Figure 42E depicts a bottom view of the housing shown in Figures 42A and 42B.

[0071] [Figure 43] FIG. 43 depicts a cross-sectional view of the applicator in a loaded configuration for deploying an analyte monitoring device from the applicator.

[0072] [Figure 44] FIG. 44 depicts a cross-sectional view of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator.

[0073] [Figure 45]Figures 45A-45C depict a top side perspective view, a side view, and a bottom perspective view of the applicator, respectively. Figure 45D depicts an exploded view of the applicator shown in Figures 45A-45C.

[0074] [Figure 46] Figures 46A-46D depict upper side perspective, top, bottom perspective, and side views, respectively, of the shuttle of the applicator. Figure 46E depicts a cross-sectional view of the shuttle taken along line 31E:31E shown in Figure 46D.

[0075] [Figure 47] Figures 47A-47C depict upper side perspective, lower side perspective, and side views, respectively, of the applicator's trigger, and Figure 47D depicts a cross-sectional view of the trigger taken along line 32D:32D shown in Figure 47C.

[0076] [Figure 48] Figures 48A-48E depict a top side perspective view, a bottom perspective view, a bottom view, and a side view, respectively, of the housing of the applicator. Figure 48E depicts a cross-sectional view of the housing taken along line 33E:33E shown in Figure 48D.

[0077] [Figure 49] FIG. 49 depicts a cross-sectional view of the applicator in a loaded configuration for deploying an analyte monitoring device from the applicator.

[0078] [Figure 50] FIG. 50 depicts a cross-sectional view of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator.

[0079] [Figure 51A] 51A-51C depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator. [Figure 51B]51A-51C depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator. [Figure 51C] 51A-51C depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator.

[0080] [Figure 51D] 51D-51F depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator. [Figure 51E] 51D-51F depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator. [Figure 51F] 51D-51F depict a bottom perspective view, a side view, and a bottom view, respectively, of the shuttle of the applicator.

[0081] [Figure 51G] 51G-51I depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a loaded configuration for deploying an analyte monitoring device from the applicator. [Figure 51H] 51G-51I depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a loaded configuration for deploying an analyte monitoring device from the applicator. [Figure 51I] 51G-51I depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a loaded configuration for deploying an analyte monitoring device from the applicator.

[0082] [Figure 51J] 51J-51L depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator. [Figure 51K] 51J-51L depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator. [Figure 51L] 51J-51L depict a top side perspective view, a cross-sectional view, and a bottom view, respectively, of the applicator in a fired configuration for deploying the analyte monitoring device from the applicator.

[0083] [Figure 51M] 51M and 51N are top and bottom perspective views, respectively, of the shuttle of the applicator with an analyte monitoring device. [Figure 51N] 51M and 51N are top and bottom perspective views, respectively, of the shuttle of the applicator with an analyte monitoring device.

[0084] [Figure 52] 52A and 52B depict top and bottom perspective views, respectively, of the shuttle of the applicator with the analyte monitoring device.

[0085] [Figure 53A] FIG. 53A depicts an exploded view of the applicator.

[0086] [Figure 53B] 53B-53E depict upper side perspective, top, bottom perspective, and cross-sectional views, respectively, of the shuttle of the applicator. [Figure 53C] 53B-53E depict upper side perspective, top, bottom perspective, and cross-sectional views, respectively, of the shuttle of the applicator. [Figure 53D] 53B-53E depict upper side perspective, top, bottom perspective, and cross-sectional views, respectively, of the shuttle of the applicator. [Figure 53E] 53B-53E depict upper side perspective, top, bottom perspective, and cross-sectional views, respectively, of the shuttle of the applicator.

[0087] [Figure 53F]53F-53H depict lower, bottom, and upper side perspective views, respectively, of the applicator's trigger. [Figure 53G] 53F-53H depict lower, bottom, and upper side perspective views, respectively, of the applicator's trigger. [Figure 53H] 53F-53H depict lower, bottom, and upper side perspective views, respectively, of the applicator's trigger.

[0088] [Figure 53I] 53I-53K depict a bottom perspective view, a cross-sectional view, and a bottom view, respectively, of the actuator of the applicator. [Figure 53J] 53I-53K depict a bottom perspective view, a cross-sectional view, and a bottom view, respectively, of the actuator of the applicator. [Figure 53K] 53I-53K depict a bottom perspective view, a cross-sectional view, and a bottom view, respectively, of the actuator of the applicator.

[0089] [Figure 54] 54A and 54B depict a perspective view and an exploded view, respectively, of the shuttle of the applicator. DETAILED DESCRIPTION OF THE INVENTION

[0090] Detailed Description Non-limiting examples of various aspects and variations of the present invention are described herein and illustrated in the accompanying drawings.

[0091] Aspects of the present subject matter are directed to a microneedle enclosure for providing a protected environment within which a microneedle array of an analyte monitoring device can be safely contained. The microneedle enclosure is releasably attached to the analyte monitoring device to protect the microneedle array prior to application of the analyte monitoring device, and is removable from the analyte monitoring device to provide for application of the analyte monitoring device (e.g., insertion of the microneedle array).

[0092] An additional aspect of the present subject matter is directed to applicator devices (also referred to as applicators) for application of an analyte monitoring device including one or more microneedle arrays to a target area of ​​a user. The applicator devices and variations described herein provide a user with safe and effective application of the analyte monitoring device such that the microneedle arrays pierce the user's skin for insertion into the skin, for example, into the upper dermal region of the skin (e.g., the papillary dermis and upper reticular dermis).

[0093] Before providing additional details regarding aspects of the microneedle enclosure and applicator device, the following provides a description of several examples of analyte monitoring devices that may be used in conjunction with the microneedle enclosure and / or applicator device described herein. The following description is intended to be exemplary, and aspects related to microneedle enclosures and applicator devices consistent with the present subject matter are not limited to the exemplary analyte monitoring devices described herein.

[0094] Generally, as described herein, an analyte monitoring system may include an analyte monitoring device worn by a user and including one or more sensors for monitoring at least one analyte of the user. The sensor may include, for example, one or more electrodes configured to perform electrochemical detection of at least one analyte. The analyte monitoring device may communicate sensor data to an external computing device for storage, display, and / or analysis of the sensor data.

[0095] For example, as shown in FIG. 1 , analyte monitoring system 100 may include analyte monitoring device 110 worn by a user, which may be a continuous analyte monitoring device (e.g., a continuous glucose monitoring device). Analyte monitoring device 110 may include, for example, a microneedle array with at least one electrochemical sensor for detecting and / or measuring one or more analytes in the user's bodily fluid. In some variations, analyte monitoring device 110 may be applied to the user using a suitable applicator 160 (e.g., any of the applicators described herein). Analyte monitoring device 110 may include one or more processors for performing analysis on the sensor data and / or a communications module (e.g., a wireless communications module) configured to communicate the sensor data to mobile computing device 102 (e.g., a smartphone) or other suitable computing device. In some variations, the mobile computing device 102 may include one or more processors that execute mobile applications to process the sensor data (e.g., display the data, analyze the data for trends, etc.) and / or provide suitable alerts or other notifications related to the sensor data and / or its analysis. In some variations, the mobile computing device 102 may perform sensor data analysis locally, although it should be understood that other computing devices may alternatively or additionally analyze the sensor data remotely and / or communicate information related to such analysis with the mobile computing device 102 (or other suitable user interface) for display to a user. Furthermore, in some variations, the mobile computing device 102 may be configured to communicate the sensor data and / or an analysis of the sensor data to one or more storage devices 106 (e.g., servers) via the network 104 for archiving data and / or other suitable information related to a user of the analyte monitoring device.

[0096] The analyte monitoring devices described herein have characteristics that improve several properties that are advantageous relative to continuous analyte monitoring devices, such as continuous glucose monitoring (CGM) devices. For example, the analyte monitoring devices described herein have improved sensitivity (the amount of sensor signal generated per given concentration of target analyte), improved selectivity (rejection of endogenous and exogenous circulating compounds that may interfere with the detection of the target analyte), and improved stability, which helps minimize changes in sensor response over time throughout storage and operation of the analyte monitoring device. In addition, compared to conventional continuous analyte monitoring devices, the analyte monitoring devices described herein have a shorter warm-up time, which enables the sensor to quickly provide a stable sensor signal following implantation, and a shorter response time, which enables the sensor to quickly provide a stable sensor signal following changes in analyte concentration in the user. Furthermore, as described in further detail below, the analyte monitoring devices described herein can be applied to and function at a variety of application sites, providing a painless sensor insertion for the user. Other properties, such as biocompatibility, sterility, and mechanical integrity, are also optimized in the analyte monitoring devices described herein.

[0097] While the analyte monitoring systems described herein may be described with reference to monitoring glucose (e.g., in users with type 2 diabetes, type 1 diabetes), it should be understood that such systems may be configured to sense and monitor other suitable analytes in addition to, or instead of, detecting other suitable analytes. As described in further detail below, target analytes suitable for detection may include, for example, glucose, ketones, lactate, and cortisol. A single target analyte may be monitored, or multiple target analytes may be monitored simultaneously (e.g., in the same analyte monitoring device). For example, monitoring other target analytes may enable monitoring of other indications such as stress (e.g., through detection of elevated cortisol and glucose) and ketoacidosis (e.g., through detection of elevated ketones).

[0098] As shown in FIG. 2A , in some variations, analyte monitoring device 110 may generally include a housing 112 and a microneedle array 140 extending outward from the housing. Housing 112 may be a wearable housing configured to be worn on a user's skin, such that microneedle array 140 extends at least partially into the user's skin. For example, housing 112 may include an adhesive such that analyte monitoring device 110 is a skin-adhesive patch that is simple and easy to apply to a user. Microneedle array 140 may be configured to include one or more electrochemical sensors (e.g., electrodes) configured to pierce the user's skin and measure one or more target analytes accessible after microneedle array 140 pierces the user's skin. In some variations, analyte monitoring device 110 may be integrated or self-contained as a single unit, which may be disposable (e.g., used for a period of time and replaced with another instance of analyte monitoring device 110).

[0099] The electronics system 120 may include various electronic components, such as a sensor circuit 124, arranged at least in part within the housing 112 and configured to perform signal processing (e.g., biasing and readout of an electrochemical sensor, converting analog signals from the electrochemical sensor to a digital signal, etc.). The electronics system 120 may also include at least one microcontroller 122 for controlling the analyte monitoring device 110, at least one communications module 126, at least one power supply 130, and / or various other suitable passive circuitry 127. The microcontroller 122 may be configured, for example, to interpret digital signals output from the sensor circuit 124 (e.g., by executing programmed routines in firmware), perform various suitable algorithms or mathematical transformations (e.g., calibration, etc.), and / or route processed data to and / or from the communications module 124. In some variations, the communications module 126 may include a suitable wireless transceiver (e.g., a Bluetooth transceiver or equivalent) for communicating data with the external computing device 102 via one or more antennas 128. For example, communications module 126 may be configured to provide unidirectional and / or bidirectional communication of data with an external computing device 102 paired with analyte monitoring device 110. Power source 130 may provide power for analyte monitoring device 110, such as for the electronics system. Power source 130 may include a battery or other suitable source and, in some variations, may be rechargeable and / or replaceable. Passive circuitry 127 may include various unpowered electrical circuits (e.g., resistors, capacitors, inductors, etc.) that provide interconnections between other electronic components, etc. Passive circuitry 127 may be configured, for example, to perform noise reduction, biasing, and / or other purposes. In some variations, electronic components in electronics system 120 may be arranged on one or more printed circuit boards (PCBs), which may, for example, be rigid, semi-rigid, or flexible.Additional details of electronics system 120 are described further below.

[0100] In some variations, the analyte monitoring device 110 may further include one or more additional sensors 150 to provide additional information that may be relevant to user monitoring. For example, the analyte monitoring device 110 may further include at least one temperature sensor (e.g., a thermistor) configured to measure skin temperature, thereby enabling temperature compensation for sensor measurements obtained by the microneedle array electrochemical sensor.

[0101] In some variations, the microneedle array 140 in the analyte monitoring device 110 may be configured to pierce a user's skin. As shown in FIG. 2B, when the device 110 is worn by a user, the microneedle array 140 may extend into the user's skin such that electrodes on distal regions of the microneedles rest within the dermis. Specifically, in some variations, the microneedles may be designed to penetrate the skin and access the upper dermal regions of the skin (e.g., the papillary dermis and upper reticular dermis) to allow the electrodes to access the interstitial fluid surrounding cells in these layers. For example, in some variations, the microneedles may generally have a height ranging from at least 350 μm to about 515 μm. In some variations, one or more microneedles may extend from the housing such that the distal end of the electrode on the microneedle is located less than about 5 mm from the skin-interfacing surface of the housing, less than about 4 mm from the housing, less than about 3 mm from the housing, less than about 2 mm from the housing, or less than about 1 mm from the housing.

[0102] In contrast to conventional continuous analyte monitoring devices (e.g., CGM devices), which typically include sensors implanted about 8 mm to about 10 mm below the skin surface in the subcutaneous or adipose layer of the skin, the analyte monitoring device 110 has a shallower microneedle insertion depth of about 0.25 mm (such that the electrodes are implanted within the upper dermal region of the skin), which provides numerous benefits. These benefits include access to dermal interstitial fluid, which contains one or more target analytes for detection, which is advantageous because at least some types of analyte measurements in dermal interstitial fluid have been found to correlate closely with those in blood. For example, glucose measurements performed using electrochemical sensors that access dermal interstitial fluid have been found to advantageously correlate highly linearly with blood glucose measurements. Thus, glucose measurements based on dermal interstitial fluid accurately represent blood glucose measurements.

[0103] Additionally, due to the shallower microneedle insertion depth of the analyte monitoring device 110, a reduced time delay in analyte detection is obtained compared to conventional continuous analyte monitoring devices. Such a shallower insertion depth positions the sensor surface in close proximity (e.g., within a few hundred micrometers or less) to the dense and well-perfused capillary bed of the reticular dermis, resulting in negligible diffusion delay from the capillaries to the sensor surface. The diffusion time is t=x 2Diffusion distance is related to diffusion distance according to ∂t / (2D), where t is the diffusion time, x is the diffusion distance, and D is the mass diffusion coefficient of the analyte of interest. Thus, positioning the analyte sensing element twice as far away from the source of the analyte in the capillaries would result in a diffusion delay time that is four times longer. Thus, conventional analyte sensors residing in the poorly vascularized adipose tissue below the dermis experience significantly longer diffusion distances from the vessels within the dermis, and thus substantial diffusion latencies (e.g., typically 5-20 minutes). In contrast, the shallower microneedle insertion depth of the analyte monitoring device 110 benefits from less diffusion latency from the capillaries to the sensor, thereby reducing the time delay in analyte detection and providing more accurate results in real time or near real time. For example, in some embodiments, the diffusion latency may be less than 10 minutes, less than 5 minutes, or less than 3 minutes.

[0104] Furthermore, when the microneedle array rests within the upper dermal region, the lower dermis beneath the microneedle array contains very high levels of vascularization and perfusion to support dermal metabolism, which allows for thermoregulation (via vasoconstriction and / or vasodilation) and provides a barrier function to help stabilize the sensing environment around the microneedles. Another advantage of a shallower insertion depth is the lack of pain receptors in the upper dermal layer, thus resulting in reduced pain sensation when the microneedle array pierces the user's skin, providing a more comfortable, minimally invasive user experience.

[0105] Thus, the analyte monitoring devices and methods described herein enable improved continuous monitoring of one or more target analytes in a user. For example, as described above, the analyte monitoring devices can be simple and easy to apply, which improves ease of use and user compliance. In addition, analyte measurement in dermal interstitial fluid can provide highly accurate analyte detection. Furthermore, compared to conventional continuous analyte monitoring devices, insertion of the microneedle array and its sensors can be less invasive and less painful for the patient. Additional benefits of other aspects of the analyte monitoring devices and methods are further described below.

[0106] 3A-3D depict a side view of analyte monitoring device 110. Figures 3A-3D depict a top side perspective view, a side view, a bottom view, and an exploded view of analyte monitoring device 110, respectively.

[0107] The analyte monitoring device 110 may include a housing that at least partially surrounds or encloses other components (e.g., electronic components) of the analyte monitoring device 110, such as for the protection of such components. For example, the housing may be configured to help prevent dust and moisture from entering the analyte monitoring device 110. In some variations, an adhesive layer may attach the housing to a surface (e.g., skin) of a user while allowing the microneedle array 140 to extend outward from the housing and into the user's skin. Additionally, in some variations, the housing may generally include rounded edges or corners and / or be thin to reduce interference with clothing or the like worn by the user.

[0108] 3A-3D, an exemplary variation of analyte monitoring device 110 may include a housing cover 320 and a base plate 330 configured to at least partially enclose the internal components of analyte monitoring device 110. For example, housing cover 320 and base plate 330 may provide an enclosure for sensor assembly 350, including microneedle array 140 and electronic components. Once assembled, microneedle array 140 extends outward from a portion of base plate 330 in a skin-facing direction (e.g., the underside) of analyte monitoring device 110.

[0109] Housing cover 320 and base plate 330 may include one or more rigid or semi-rigid protective shell components that may be coupled together, for example, via suitable fasteners (e.g., mechanical fasteners), mechanical interlocking or interlocking features, and / or engineered fits. Housing cover 320 and base plate 330 may include radiused edges and corners and / or other atraumatic features. When coupled together, housing cover 320 and base plate 330 may form an interior volume that houses internal components, such as sensor assembly 350. For example, the internal components arranged within the interior volume may be arranged in a compact, thin stack, as sensor assembly 350.

[0110] Analyte monitoring device 110 may include one or more adhesive layers for attaching analyte monitoring device 110 (e.g., housing cover 320 and base plate 330 coupled together) to a surface (e.g., skin) of a user. As shown in FIG. 3D , the one or more adhesive layers may include inner adhesive layer 342 and outer adhesive layer 344. Inner adhesive layer 342 may adhere to base plate 330, and outer adhesive layer 344 may adhere to inner adhesive layer 342 and provide adhesive on its outward-facing side for (e.g., temporary) adhesion to the user's skin. Inner adhesive layer 342 and outer adhesive layer 344 together act as a double-sided adhesive for adhering analyte monitoring device 110 to the user's skin. Outer adhesive layer 344 may be protected by a release liner, which the user removes prior to skin application, exposing the adhesive. In some variations, a single adhesive layer is provided. In some variations, the outer adhesive layer 344, the inner adhesive layer 342, and / or the single adhesive layer may have a perimeter that extends beyond the perimeter or rim of the housing cover 320 and the base plate 330. This may increase the surface area for attachment and increase the stability of retention or attachment to the user's skin. The inner adhesive layer 342, the outer adhesive layer 344, and / or the single adhesive layer each have an opening that allows for the passage of the outwardly extending microneedle array 140, as described further below. The openings in the inner adhesive layer 342 and the outer adhesive layer 344 may generally align with one another, but in some variations, they may be different sizes, such that one opening is smaller than the other. In some variations, the openings are approximately the same size.

[0111] The base plate 330 has a first surface (e.g., an outwardly exposed surface) opposite a second surface and serves as a support and / or connecting structure and as a protective cover for the sensor assembly 350. The base plate 330 is sized and shaped to be attached to the housing cover 320. The base plate 330 is sized and shaped to be attached to the housing cover 320 such that the outer edges of the base plate 330 are in contact with the housing cover 320. coverThe base plate 330 may be molded to fit securely within the housing cover 320 so that it aligns with a corresponding edge of the opening in 320. The alignment may be such that no gap exists between the outer edge of the base plate 330 and the corresponding edge of the opening in the housing cover 320.

[0112] A connecting member 332 may be formed near the center or central region of the first surface of the base plate 330. The connecting member 332 is a protrusion (e.g., a protruding hub) with a sidewall extending from the first surface of the base plate 330, the first surface being generally parallel to the first surface of the base plate 330. The sidewall extends from the edge of the first surface of the connecting member 332 to the first surface of the base plate 330. The remainder of the first surface of the base plate 330 surrounding the connecting member 332 may be flat or generally flat. One or more connector features 336 extend outward from the sidewall of the connecting member 332 and releasably engage with a corresponding connector of the microneedle enclosure, as described further below. The first surface and sidewall of the connecting member 332 partially define a cavity. The cavity may further be defined through a portion of the base plate 330 adjacent (e.g., below) the connecting member 332. The cavity is accessible through an opening on the second surface of the base plate 330. An opening 334 is formed through the first surface of the connecting member 332. The opening 334 may be sized and shaped so that the microneedle array 140 fits securely within and extends through the opening 334. For example, the sidewalls of the microneedle array 140 may align with the corresponding sidewalls of the opening 334. In some variations, the opening 334 may be sized and shaped to correspond to the area surrounding the microneedle array 140. The openings in the inner adhesive layer 342 and the outer adhesive layer 344 (or single adhesive layer) are sized so that the connecting member 332 extends through the opening without interfering with the adhesive layers. For example, the diameter of the opening in the inner adhesive layer 342 and the diameter of the opening in the outer adhesive layer 344 are larger than those of the connecting member 332. In some variations, the openings in the inner adhesive layer 342 and / or the openings in the outer adhesive layer 344 (or of the single adhesive layer) are adjacent to the sidewalls of the connecting member 332, and gaps accommodate one or more connector features 336. In some variations, one or more slits or notches may be formed in the inner adhesive layer 342, the outer adhesive layer 344, and / or the single adhesive layer and extend from the openings to aid in the placement of the individual adhesive layers.

[0113] Although the housing cover 320 and base plate 330 depicted in FIGS. 3A-3D are generally circular, with the housing cover 320 having a dome shape, in other variations, the housing cover 320 and base plate 330 may have any suitable shape. For example, in other variations, the housing cover 320 and base plate 330 may be generally prism-shaped, elliptical, triangular, rectangular, pentagonal, hexagonal, or other suitable shapes. The outer adhesive layer 344 (or single adhesive layer) extends outward from the housing cover 320 and base plate 330 and may extend beyond the perimeter of the housing cover 320. The outer adhesive layer 344 (or single adhesive layer) may be circular, as shown in FIGS. 3A-3D , or may have an elliptical, triangular, rectangular, pentagonal, hexagonal, or other suitable shape, and need not be the same shape as the housing cover 320 and / or base plate 330.

[0114] 4A-4E depict a side view of sensor assembly 350 of analyte monitoring device 110 in an exploded perspective view, an exploded side view, a bottom perspective view, a side view, and a top side perspective view, respectively.

[0115] The sensor assembly 350 includes microneedle array components and electronic components for analyte detection and measurement, and implements the analyte detection and processing aspects of the microneedle array-based continuous analyte monitoring device 110. In some variations, the sensor assembly 350 is a compact, thin laminate contained at least in part within an interior volume defined by the housing cover 320 and the base plate 330.

[0116] In some variations, the sensor assembly 350 includes a microneedle array assembly 360 and an electronics assembly 370 that are interconnected and implement the microneedle array analyte detection and processing aspects described further herein. In some variations, the electronics assembly 370 includes a primary printed circuit board (PCB) 450 onto which the electronic components are connected, and the microneedle array assembly 360 includes a secondary printed circuit board (PCB) 420 onto which the microneedle array 140 is connected.

[0117] In some variations, the microneedle array assembly 360 includes, in addition to the secondary PCB 420 and the microneedle array 140, an epoxy skirt 410 and a secondary PCB connector 430. The microneedle array 140 is coupled to the top side (e.g., the outward-facing side) of the secondary PCB 420 so that the individual microneedles of the microneedle array 140 are exposed, as described with reference to Figures 3A-3D. The secondary PCB connector 430 is coupled to the back side, opposite the top side, of the secondary PCB 420. The secondary PCB connector 430 may be an electromechanical connector and may communicatively couple to the primary PCB 450 through a primary PCB connector 470 on the top side (e.g., the outward-facing side) of the primary PCB 450 to enable signal communication between the secondary PCB 420 and the primary PCB 450. For example, signals from microneedle array 140 may be communicated to primary PCB 450 through secondary PCB 420 , secondary PCB connector 430 , and primary PCB connector 470 .

[0118] The secondary PCB 420 is, in part, a substrate for the microneedle array 140 to be mounted on. base The height of the secondary PCB 420 can be selected to help ensure that the microneedle array 140 is properly inserted into the user's skin. base The first surface (e.g., the outward-facing surface) of the connecting member 332 of the plate 330 may act as a stop for microneedle insertion. If the secondary PCB 420 has a reduced height and its top surface is flush or nearly flush with the first surface of the connecting member 332, the connecting member 332 may prevent the microneedle array 140 from being fully inserted into the skin.

[0119] In some variations, other components (e.g., electronic components such as sensors or other components) may also be connected to secondary PCB 420. For example, secondary PCB 420 may be sized and shaped to accommodate electronic components on the top or back side of secondary PCB 420.

[0120] 3C and 3D , the epoxy skirt 410 may be deposited along the edge (e.g., periphery) of the microneedle array 140 to provide a secure fit of the microneedle array 140 within the opening 334 formed in the connecting member 332 of the base plate 330 and / or to soften sharp edges along the microneedle array 140. For example, the epoxy skirt 410 may occupy the portion of the opening 334 that is not filled by the microneedle array 140 and / or the portion of the cavity defined in the base plate 330 that is not filled by the secondary PCB 420. The epoxy skirt 410 may also provide a transition from the edge of the microneedle array 140 to the edge of the secondary PCB 420. In some variations, the epoxy skirt 410 may be replaced or supplemented by a gasket (e.g., a rubber gasket) or the like.

[0121] Electronics assembly 370, having primary PCB 450, includes battery 460 coupled to the back side of primary PCB 450, opposite the top side onto which primary PCB connector 470 is coupled. In some variations, battery 460 may be coupled on the top side of primary PCB 450 and / or in other arrangements.

[0122] 4F-4H depict a side view of an alternative variation of sensor assembly 350 of analyte monitoring device 110. Perspective exploded, side exploded, and side views of sensor assembly 350 are provided in FIGS. 4F-4H, respectively.

[0123] As shown, the sensor assembly 350 incorporates an additional PCB component, the intermediate PCB 425. In some variations, the intermediate PCB 425 is part of the microneedle array assembly 360 and is positioned between and connected to the secondary PCB 420 and the microneedle array 140. The intermediate PCB 425 may be added to increase the height of the microneedle array assembly 360 so that the microneedle array 140 extends a further distance from the base plate 330, which may aid in the insertion of the microneedle array 140 into a user's skin. The microneedle array 140 is bonded to the top side (e.g., the outward-facing side) of the intermediate PCB 425 so that the individual microneedles of the microneedle array 140 are exposed, as described with reference to FIGS. 3A-3D . The secondary PCB 420 is bonded to the back side, opposite the top side, of the intermediate PCB 425, and the secondary PCB connector 430 is bonded to the back side, opposite the top side, of the secondary PCB 420. An epoxy skirt 410 (which may be replaced or supplemented by a gasket or equivalent) provides a transition from the edge of the microneedle array 140 to the edge of the intermediate PCB 425 .

[0124] The intermediate PCB 425, together with the secondary PCB 420, in part, supports the microneedle array 140 thereon. base The incorporation of the intermediate PCB 425 determines the distance the microneedle array 140 protrudes through the opening 334 in the plate 330. The incorporation of the intermediate PCB 425 provides additional height and helps ensure that the microneedle array 140 is properly inserted into the user's skin. In some variations, the top side (e.g., the outward-facing side) of the intermediate PCB 425 extends outward from the opening 334 so that the first surface (e.g., the upper exposed surface) of the connecting member 332 surrounding the opening 334 does not prevent the microneedle array from being fully inserted into the skin. In some variations, the top side (e.g., the outward-facing side) of the intermediate PCB 425 does not extend outward from the opening 334, but the increased height (by incorporating the intermediate PCB 425) prevents the microneedle array 140 from being fully inserted into the skin. base Ensure that it protrudes a sufficient distance from the plate 330 .

[0125] In some variations, a microneedle enclosure may be provided for releasable attachment to the analyte monitoring device 110. The microneedle enclosure may provide a protective environment or enclosure within which the microneedle array 140 may be safely contained, thereby ensuring the integrity of the microneedle array 140 during certain stages of manufacturing and shipping of the analyte monitoring device 110 prior to application of the analyte monitoring device 110. The microneedle enclosure may be releasable or removable from the analyte monitoring device 110, as further described herein, allowing the microneedle array 140 to be exposed and ready for insertion into a user's skin.

[0126] In some variations, the microneedle enclosure provides an enclosed and sealed environment within which the microneedle array 140 may be contained, thereby providing an environment within which the microneedle array 140 may be sterilized. For example, the microneedle enclosure, along with the microneedle array 140, may be subjected to a sterilization process during which the sterilant permeates the microneedle enclosure such that the microneedle array 140 is also sterilized. Because the microneedle array 140 is contained within the enclosed environment, the microneedle array 140 remains sterile until it is removed from the enclosed environment.

[0127] 5A-5D depict a side view of a microneedle enclosure 500 in an exploded view, a first side and side cross-sectional view, a second side and side cross-sectional view, and a bottom perspective view, respectively. The microneedle enclosure 500 includes a capsule 510, a clamp 520, and a biasing element 530 (e.g., a spring). In some variations, the microneedle enclosure 500 may further include a force concentrator 540.

[0128] The capsule 510 is a housing, enclosure, or the like whose sidewalls surround and / or enclose the microneedle array 140, providing an enclosed and sealed environment for the microneedle array 140. The capsule 510 has an opening at its distal end through which the microneedle array 140 is positioned such that the inner portion of the capsule's 510 sidewall surrounds the microneedle array 140. A bumper 512 may be positioned at the distal end of the capsule 510 such that the bumper 512 surrounds the opening of the capsule 510 at the distal end. The bumper 512 may be a ring-shaped elastomeric bumper or the like that provides a tight seal to be maintained around the distal end of the capsule 510. The bumper 512 may be sized to correspond to the size and shape of the opening of the capsule 510 at the distal end. The inner periphery of capsule 510 (e.g., the periphery of the opening) may match or substantially match the footprint of microneedle array 140. For example, the inner periphery of capsule 510 may be sized and shaped to match the outer periphery of microneedle array 140, providing for microneedle array 140 to be fully contained within capsule 510, with the microneedles extending into capsule 510.

[0129] Clamp 520 includes a cavity defined by the sidewalls of clamp 520. The cavities may include a first cavity 522 and a second cavity 524, each defined by a sidewall of clamp 520. Second cavity 524 is adjacent to first cavity 522 in a region proximal to first cavity 522, and second cavity 524 is a proximal extension of first cavity 522 such that first cavity 522 and second cavity 524 are fluidly connected. First cavity 522 is sized and shaped to accommodate capsule 510. An opening at the distal end of clamp 520 provides an access point into first cavity 522, allowing capsule 510 to fit through the opening and into first cavity 522. Second cavity 524 is sized and shaped to accommodate biasing element 530. When biasing element 530 and capsule 510 are positioned within clamp 520 (e.g., through an opening in the distal end of clamp 520), biasing element 530 is securely but movably contained within second cavity 524, and the outer wall of capsule 510 may be aligned with and abut against the side wall of first cavity 522. In some variations, one or more portions of the outer wall of capsule 510 contact a respective one or more portions of first cavity 522 such that capsule 510 is wedged or tightly fitted within first cavity 522, making capsule 510 integral with clamp 520. Biasing element 530 generally corresponds in size and shape to second cavity 524 and may extend distally from an upper region of second cavity 524 to or near the top surface of capsule 510. The diameter of biasing element 530 may be slightly less than the inner diameter of second cavity 524, limiting horizontal movement of biasing element 530 within clamp 520. Biasing element 530 may be a coiled metal spring, a plastic leaf spring, a coiled plastic spring, or any form of spring capable of providing compliance between clamp 520 and capsule 510, as described further herein.

[0130] In some variations, the force concentrator 540 may be positioned within the biasing element 530, with a distal region extending out from the biasing element 530 and contacting the top surface of the capsule 510. For example, the force concentrator 540 may include a shaft and a head. The shaft may fit within the biasing element 530, and the head may extend through the biasing element 530 at a distal end and contact the top surface of the capsule 510. The biasing element 530, and optionally the force concentrator 540, are incorporated to provide a sealing downward force on the capsule 510 and bumper 512, as described further herein, to maintain a sealed enclosure for the microneedle array 140 when the clamp 520 is engaged with the analyte monitoring device 110. The force concentrator 540 provides a downward force to the engaged top surface of the capsule 510 and eliminates the transmission of torque to the bumper 512 during the manufacturing and / or assembly process. For example, the force concentrator 540 eliminates rotation of the damper 512 during the manufacturing and / or assembly process.

[0131] Clamp 520 further includes an outer engagement feature 526 and a locking tab 528. Outer engagement feature 526 is configured to engage a portion of an applicator device, as described further herein. Locking tab 528 is formed on a separate inner portion of a side wall of clamp 520 at the distal end of clamp 520, as best shown in FIG. 5D . Locking tab 528 may be a protrusion extending orthogonally outward from the inner portion of the side wall of clamp 520 and may be configured to releasably engage base plate 330, as described further below.

[0132] 5E-5G depict side views of the microneedle enclosure 500, the base plate 330 of the analyte monitoring device 110, and the releasable connection therebetween. The microneedle enclosure 500 is configured to be releasably attached to or coupled to the base plate 330 through engagement with the connecting member 332. The microneedle array assembly 360 portion of the sensor assembly 350 fits within the cavity formed by the base plate 330 and the connecting member 332, with the microneedle array 140 extending through the opening 334 in the base plate 330. As shown in the side cross-sectional view of FIG. 5G, upon attachment of the microneedle enclosure 500 and the base plate 330, the microneedle array 140 is contained within a capsule 510, with a bumper 512 providing a seal between the capsule 510 and the base plate 330. In some variations, the bottom edge of the sidewall of the microneedle enclosure 500 interfaces and / or abuts the first surface of the base plate 330 around and / or adjacent the outer edge of the connecting member 322. In some variations, the bottom edge of the sidewall of the capsule 510 and the bottom edge of the bumper 512 interface and / or abut the first surface of the connecting member 332 around and / or adjacent the outer edge of the opening 334. In some variations, the outer diameter of the capsule 510 is the same as or slightly less than the diameter of the first surface of the connecting member 322. The diameter of the opening of the capsule 510 is large enough to accommodate the opening 334 without interfering with the microneedle array 140. The sidewalls of the opening of capsule 510 may interface and / or abut the edge surrounding microneedle array 140 such that the sidewalls of the opening of capsule 510 surround the edge of microneedle array 140 .

[0133] To form a releasable attachment or coupling between the base plate 330 and the microneedle enclosure 500, the connector features 336 of the connecting member 332 releasably engage with the locking tabs 528 of the microneedle enclosure 500. In some variations, the connector features 336 may be bayonet connectors that engage and disengage from the locking tabs 528 through a twisting or rotating motion. For example, the connector features 336 may include extending leaves that project orthogonally from an upper region of the connecting member 332. Each extending leaf may terminate at one end, with a stop feature (e.g., a vertical wall or vertically extending barrier) extending from the upper edge of the respective extending leaf to the first surface of the base plate 330. The connector features 336 may be positioned circumferentially around the outer edge of the connecting member 332, and each connector feature 336 may correspond to a respective locking tab 528 of the microneedle enclosure 500. The locking tab 528 interfaces with the connector feature 336 by sliding beneath the extended leaf and engaging a stop feature in response to rotation of the microneedle enclosure 500 relative to the base plate 330. In some variations, the microneedle enclosure 500 is placed over the connecting member 332 and rotated until further rotation is prevented by the locking tab 528 engaging a stop feature on the connector feature 336. Rotation in the opposite direction disengages the locking tab 528 from the stop feature, allowing the microneedle enclosure 500 to disengage from the connecting member 332, at which point the microneedle enclosure 500 can be lifted or pulled away from the base plate 330. Other types of connecting members that form a releasable connection may also be used. In some variations, three connector features 336 and locking tabs 528 may be incorporated. In other variations, one, two, four, or more pairs of connector features 336 and locking tabs 528 may be incorporated.

[0134] 5G, when the microneedle enclosure 500 is connected to the base plate 330, which includes the microneedle array assembly 360, the capsule 510 is aligned around the microneedle array 140 on the first surface of the connecting member 322. When the microneedle enclosure 500 is positioned over the connecting member 322 and twisted to engage one or more connector features 336, the biasing element 530 is biased to maintain a stable connection between the capsule 510 and the clamp 520. The force concentrator 540 provides a downward force to the capsule 510 and the bumper 512, eliminating the transmission of torque to the bumper 512 so that it does not rotate during the twisting action. The sterile barrier provided by the capsule 510 and the bumper 512 is therefore maintained. The inner periphery of the opening of the capsule 510 and the edge of the microneedle array 140 are tightly sealed such that the clamp 520, capsule 510, buffer 512, biasing element 530, and force concentrator 540 provide a tight enclosure around the microneedle array 140.

[0135] The microneedle array assembly 360, including the microneedle array 140 fitted into the base plate 330 with the microneedle enclosure 500 bonded thereto, may be sterilized. For example, a radiation sterilization method may be applied. In some variations, the components may be sterilized in 10 -6 sterilized to a Sterility Assurance Level (SAL) of 100 psi. Notably, sterilization occurs without the microneedle array assembly 360 being connected to the electronics assembly 370. After the sterilization process, the base plate 330 is attached to the housing cover 320, within which the electronics assembly 370 is positioned. Attachment involves establishing a connection between the microneedle array assembly 360 and the electronics assembly 370 through the individual PCB connectors 430 and 470. Because the microneedle array 140 is contained within a sealed microneedle enclosure 500, the sterile environment within which the microneedle array 140 is contained is not compromised. The assembled analyte monitoring device 110, with the attached microneedle enclosure 500, may be contained within an applicator device, as further described herein.

[0136] The configuration of the microneedle enclosure 500 as described herein allows for high-volume batch sterilization. For example, multiple assemblies including the microneedle array assembly 360, the base plate 330, and the microneedle enclosure 500 may be assembled as described herein. The multiple assemblies may then be exposed to radiation to sterilize each microneedle array 140. In some variations, one or more trays, containers, or the like containing multiple assemblies may be placed in an enclosed environment or sterilization chamber, and radiation may be applied to them. This results in multiple assemblies being sterilized simultaneously, thus enabling large-scale manufacturing of analyte monitoring devices.

[0137] In some variations, the electronics system of the analyte monitoring device may include an analog front end. The analog front end may include a sensor circuit (e.g., sensor circuit 124 as shown in FIG. 2A) that converts analog current measurements into digital values ​​that can be processed by a microcontroller. The analog front end may include a programmable analog front end, suitable for use with electrochemical sensors, for example. For example, the analog front end may include MAX30131, MAX30132, or MAX30134 components (having one, two, and four channels, respectively) available from Maxim Integrated (San Jose, CA), which are ultra-low-power programmable analog front ends for use with electrochemical sensors. The analog front end may also include AD5940 or AD5941 components available from Analog Devices (Norwood, MA), which are high-precision, impedance, and electrochemical front ends. Similarly, the analog front end may also include the LMP91000, available from Texas Instruments (Dallas, TX), a configurable analog front-end potentiostat for low-power chemical sensing applications. The analog front end may provide a complete measurement path, including bias and an analog-to-digital converter (ADC). Ultra-low power may enable continuous biasing of the sensor to maintain accuracy and fast response when measurements are required over long durations (e.g., 7 days) using a body-worn, battery-operated device.

[0138] In some variations, the analog front-end device may be compatible with both two- and three-terminal electrochemical sensors, such as to enable both DC and AC current measurements and electrochemical impedance spectroscopy (EIS) measurement capabilities. Additionally, the analog front-end may include an internal temperature sensor and programmable voltage reference, support external temperature monitoring and external reference sources, and integrate voltage monitoring of bias and supply voltages for safety and compliance.

[0139] In some variations, the analog front end may include a multi-channel potentiostat to multiplex sensor inputs and handle multiple signal channels. For example, the analog front end may include a multi-channel potentiostat such as that described in U.S. Pat. No. 9,933,387, which is incorporated herein by reference in its entirety.

[0140] In some variations, the analog front end and peripheral electronics may be integrated into an application specific integrated circuit (ASIC), which may help to reduce costs, for example. This integrated solution may, in some variations, include a microcontroller, as described below.

[0141] In some variations, the electronics system of the analyte monitoring device may include at least one microcontroller (e.g., controller 122 as shown in FIG. 2A). The microcontroller may include, for example, a processor with integrated flash memory. In some variations, the microcontroller in the analyte monitoring device may be configured to perform analyses and correlate sensor signals to analyte measurements (e.g., glucose measurements). For example, the microcontroller may execute programmed routines in firmware, interpret digital signals (e.g., from the analog front end), perform any associated algorithms and / or other analyses, and route processed data to and / or from a communications module. Keeping the analyses onboard the analyte monitoring device may, for example, enable the analyte monitoring device to broadcast analyte measurements to multiple devices in parallel (e.g., mobile computing devices such as smartphones or smartwatches, therapy delivery systems such as insulin pens or pumps, etc.), while ensuring that each connected device has identical information.

[0142] In some variations, the microcontroller may be configured to activate and / or deactivate the analyte monitoring device in response to one or more detected conditions. For example, the device may be configured to power on the analyte monitoring device in response to insertion of the microneedle array into the skin. This may enable a power-saving feature, for example, where the battery is disconnected until the microneedle array is placed within the skin, at which point the device may begin broadcasting sensor data. Such a feature may help, for example, to improve the shelf life of the analyte monitoring device and / or simplify the analyte monitoring device-external device pairing process for the user.

[0143] As illustrated in the schematic diagram of FIG. 6A, in some variations, a microneedle array 600 for use in sensing one or more analytes may include one or more microneedles 610 protruding from a substrate surface 602. The substrate surface 602 may be, for example, generally planar, and the one or more microneedles 610 may protrude orthogonally from the planar surface, generally as shown in FIG. 6B. The microneedle 610 may include a body portion 612 (e.g., a shaft) and a tapered distal portion 614 configured to pierce a user's skin. In some variations, the tapered distal portion 614 may terminate in an insulated distal apex 616. The microneedle 610 may further include an electrode 620 on the surface of the tapered distal portion. In some variations, electrode-based measurements may be performed at the interface between the electrode and interstitial fluid located within the body (e.g., on the outer surface of the entire microneedle). In some variations, the microneedle 610 may have a solid core (e.g., a solid body portion), while in some variations, the microneedle 610 may include one or more lumens, which may be used, for example, for drug delivery or sampling of dermal interstitial fluid. Other microneedle variations, such as those described below, may similarly include either a solid core or one or more lumens.

[0144] The microneedle array 600 may be formed, at least in part, from a semiconductor (e.g., silicon) substrate and include various material layers applied and shaped using various suitable microelectromechanical systems (MEMS) fabrication techniques (e.g., deposition and etching techniques), as described further below. The microneedle array may be reflow soldered to the circuit board, similar to a typical integrated circuit. Furthermore, in some variations, the microneedle array 600 may include a three-electrode setup including a working (sensing) electrode having an electrochemical sensing coating (including a biorecognition element such as an enzyme) that enables detection of a target analyte, a reference electrode, and a counter electrode. In other words, the microneedle array 600 may include at least one microneedle 610 including a working electrode, at least one microneedle 610 including a reference electrode, and at least one microneedle 610 including a counter electrode. Additional details of these types of electrodes are described in more detail below.

[0145] In some variations, the microneedle array 600 may include multiple microneedles that are insulated so that the electrodes on each microneedle within the multiple microneedles are individually addressable and electrically isolated from every other electrode on the microneedle array. The resulting individual addressability of the microneedle array 600 may allow greater control over the function of each electrode, as each electrode may be probed separately. For example, the microneedle array 600 may be used to provide multiple independent measurements of a given target analyte, improving the sensing reliability and accuracy of the device. Furthermore, in some variations, the electrodes of multiple microneedles may be electrically connected to produce enhanced signal levels. As another example, the same microneedle array 600 may additionally or alternatively be interrogated to simultaneously measure multiple analytes and provide a more comprehensive assessment of physiological status. For example, as illustrated in the schematic diagram of FIG. 7 , a microneedle array may include a portion of microneedles for detecting a first analyte A, a second portion of microneedles for detecting a second analyte B, and a third portion of microneedles for detecting a third analyte C. It should be understood that a microneedle array may be configured to detect any suitable number of analytes (e.g., one, two, three, four, five, or more, etc.). Suitable target analytes for detection may include, for example, glucose, ketones, lactate, and cortisol. For example, in some variations, ketones may be detected in a manner similar to that described in U.S. Patent Application No. 16 / 701,784 (herein incorporated by reference in its entirety). Thus, the individual electrical addressability of the microneedle array 600 provides greater control and flexibility of the sensing function of the analyte monitoring device.

[0146] In some variations of microneedles (e.g., microneedles with a working electrode), the electrode 620 may be located proximal to the insulated distal apex 616 of the microneedle. In other words, in some variations, the electrode 620 does not cover the apex of the microneedle. Rather, the electrode 620 may be offset from the apex or tip of the microneedle. An electrode 620 that is proximal to or offset from the insulated distal apex 616 of the microneedle advantageously provides more accurate sensor measurements. For example, this arrangement prevents electric field concentration at the microneedle apex 616 during manufacturing, thereby avoiding non-uniform deposition of sensing chemicals on the surface of the electrode 620, which would result in defective sensing.

[0147] As another example, placing the electrode 620 offset from the microneedle apex further improves sensing accuracy by reducing undesirable signal artifacts and / or erroneous sensor readings caused by stresses responsive to microneedle insertion. The distal apex of the microneedle is the first area to penetrate into the skin and therefore experiences the majority of stresses caused by mechanical shearing, which involves tearing or cutting the skin. If the electrode 620 is placed on the apex or tip of the microneedle, this mechanical stress may delaminate the electrochemical sensing coating on the electrode surface and / or transfer a small, but interfering, amount of tissue onto the active sensing portion of the electrode as the microneedle is inserted. Therefore, placing the electrode 620 sufficiently offset from the microneedle apex can improve sensing accuracy. For example, in some variations, the distal edge of the electrode 620 may be located at least about 10 μm (e.g., about 20 μm to about 30 μm) from the distal apex or tip of the microneedle, as measured along the longitudinal axis of the microneedle.

[0148] The body portion 612 of the microneedle 610 may further include a conductive pathway extending between the electrode 620 and a back electrode or other electrical contact (e.g., arranged on the back surface of the microneedle array substrate). The back electrode may be soldered to a circuit board, allowing electrical communication with the electrode 620 via a conductive pathway. For example, during use, the in vivo sensed current (inside the dermis) measured at the working electrode is queried by the back electrical contact, and the electrical connection between the back electrical contact and the working electrode is facilitated by the conductive pathway. In some variations, this conductive pathway may be facilitated by a metal via extending through the interior of the microneedle body portion (e.g., shaft) between the proximal and distal ends of the microneedle. Alternatively, in some variations, the conductive pathway may be provided by forming the entire body portion from a conductive material (e.g., doped silicon). In some of these variations, the entire substrate on which the microneedle array 600 is constructed may be electrically conductive, as described below, and each microneedle 610 in the microneedle array 600 may be electrically isolated from adjacent microneedles 610. For example, in some variations, each microneedle 610 in the microneedle array 600 may be electrically isolated from adjacent microneedles 610 using an insulating barrier comprising an electrically insulating material (e.g., a dielectric material such as silicon dioxide) surrounding the conductive pathway extending between the electrode 620 and the backside electrical contact. For example, the body portion 612 may include an insulating material that forms a sheath around the conductive pathway, thereby preventing electrical communication between the conductive pathway and the substrate. Other exemplary variations in structure that allow for electrical isolation between microneedles are described in further detail below.

[0149] Such electrical isolation between microneedles in a microneedle array allows the sensors to be individually addressable. This individual addressability advantageously allows for independent, parallelized measurements between sensors and dynamic reconfiguration of sensor assignments (e.g., to different analytes). In some variations, the electrodes in a microneedle array can be configured to provide redundant analyte measurements, which is an advantage over conventional analyte monitoring devices. For example, redundancy can improve performance by improving accuracy (e.g., averaging multiple analyte measurements for the same analyte, reducing the effect of extremely high or low sensor signals on analyte level determinations) and / or improving the reliability of the device by reducing the likelihood of complete failure.

[0150] In some variations, as described in more detail below with individual different variations of microneedles, the microneedle array may be formed, at least in part, using suitable semiconductor and / or MEMS processing techniques and / or mechanical cutting or dicing. Such processes may be advantageous, for example, for enabling large-scale, cost-effective manufacturing of microneedle arrays. For example, in some variations, the microneedle array may be formed, at least in part, using the techniques described in U.S. Patent Application No. 15 / 913,709 (incorporated herein by reference in its entirety).

[0151] Described herein are several exemplary variations of microneedle structures that incorporate one or more of the microneedle features described above with respect to microneedle arrays in analyte monitoring devices.

[0152] In some variations, the microneedle may have a generally cylindrical body portion and a tapered distal portion with an electrode. For example, Figures 8A-8C illustrate an exemplary variation of a microneedle 800 extending from a substrate 802. Figure 8A is a side cross-sectional view of a schematic of the microneedle 800, while Figure 8B is a perspective view of the microneedle 800, and Figure 8C is a detailed perspective view of the distal portion of the microneedle 800. As shown in Figures 7B and 8C, the microneedle 800 may include a cylindrical body portion 812, a tapered distal portion 814 terminating in an insulated distal apex 816, and a ring electrode 820 comprising a conductive material (e.g., Pt, Ir, Au, Ti, Cr, Ni, etc.) and arranged on the tapered distal portion 814. As shown in Figure 8A, the ring electrode 820 may be proximal to (or offset or spaced from) the distal apex 816. For example, the electrode 820 may be electrically insulated from the distal apex 816 by a distal insulating surface 815a comprising an insulating material (e.g., SiO2). In some variations, the electrode 820 may also be electrically insulated from the columnar body portion 812 by a second distal insulating surface 815b. The electrode 820 may be in electrical communication with a conductive core 840 (e.g., a conductive path) along the body portion 812 that passes to a backside electrical contact 830 (e.g., made from a Ni / Au alloy) or other electrical pad in or on the substrate 802. For example, the body portion 812 may include a conductive core material (e.g., highly doped silicon). As shown in FIG. 8A, in some variations, an insulating moat 813 comprising an insulating material (e.g., SiO2) may be arranged around (e.g., around the periphery of) the body portion 812 and extend at least partially through the substrate 802. Thus, insulating moat 813 may help, for example, to prevent electrical contact between conductive core 840 and surrounding substrate 802. Insulating moat 813 may further extend across the surface of body portion 812. The upper and / or lower surfaces of substrate 802 may also include a layer of substrate insulator 804 (e.g., SiO2). Thus, the insulation provided by insulating moat 813 and / or substrate insulator 804 may contribute, at least in part, to the electrical isolation of microneedles 800, enabling individual addressability of microneedles 800 within a microneedle array.Additionally, in some variations, insulating moats 813 extending across the surface of body portion 812 may serve to increase the mechanical strength of the microneedle 800 structure.

[0153] The microneedle 800 may be formed, at least in part, by suitable MEMS processing techniques, such as plasma etching, also known as dry etching. For example, in some variations, the insulating moat 813 around the microneedle body portion 812 may be formed by first forming a trench in a silicon substrate from the backside of the substrate by deep reactive ion etching (DRIE), and then filling the trench with a SiO2 / polycrystalline silicon (poly-Si) / SiO2 sandwich structure by low-pressure chemical vapor deposition (LPCVD) or other suitable process. In other words, the insulating moat 813 passivates the surface of the microneedle body portion 812 and may continue as a buried feature in the substrate 802 near the proximal portion of the microneedle. By primarily comprising a silicon compound, the insulating moat 813 may provide good filling and adhesion to adjacent silicon walls (e.g., of the conductive core 840, substrate 802, etc.). The sandwiched structure of the insulating moat 813 further provides excellent coefficient of thermal expansion (CTE) matching with the adjacent silicon, which may advantageously help reduce defects, cracks, and / or other thermally induced weaknesses within the insulating moat 813.

[0154] The tapered distal portion may be shaped from the front side of the substrate by isotropic dry etching, and the body portion 812 of the microneedle 800 may be formed by DRIE. The front side metal electrode 820 may be deposited and patterned on the distal portion by specialized lithography (e.g., electron beam evaporation) that allows metal deposition within the desired annular area for the electrode 820 without coating the distal apex 816. Additionally, a Ni / Au backside electrical contact 830 may be deposited by a suitable MEMS fabrication technique (e.g., sputtering).

[0155] The microneedle 800 may have any suitable dimensions. By way of example, in some variations, the microneedle 800 may have a height of about 300 μm to about 500 μm. In some variations, the tapered distal portion 814 may have a tip angle of about 60 degrees to about 80 degrees and an apex diameter of about 1 μm to about 15 μm. In some variations, the surface area of ​​the ring electrode 820 may be about 9,000 μm. 2 ~Approx. 11,000μm 2 or approximately 10,000 μm 2 Figure 9 illustrates various dimensions of an exemplary variation of a pillar-shaped microneedle with a tapered distal portion and a ring electrode, similar to microneedle 800 described above.

[0156] 10A-10F illustrate another exemplary variation of a microneedle 1000 having a generally cylindrical body portion extending from a substrate 1002 having an upper surface 1004. The microneedle 1000 may be similar to the microneedle 800 described above, except as described below. For example, as shown in FIG. 10B , similar to the microneedle 800, the microneedle 1000 may include a cylindrical body portion 1012 and a tapered distal portion disposed on a cylinder 1013 and terminating in an insulated distal apex 1016. The cylinder 1013 may be insulated and have a smaller diameter than the cylindrical body portion 1012. The microneedle 1000 may further include a ring electrode 1020 comprising a conductive material and disposed on the tapered distal portion at a location proximal to (or offset or spaced from) the distal apex 1016. Other elements of microneedle 1000 as shown in FIGS. 10A-10F have numbering similar to the corresponding elements of microneedle 800.

[0157] However, the electrode 1020 on the microneedle 1000 may include a tip contact groove 1022. This contact groove may be configured to help establish ohmic contact between the electrode 1020 and the underlying conductive core 1040 of the microneedle. In some variations, the shape of the tip contact groove 1022 may include an annular recess formed in the surface of the conductive core 1040 (e.g., in the body portion of the microneedle or otherwise in contact with a conductive path within the body portion) such that when the electrode 1020 material is deposited on the conductive core 1040, the electrode 1020 with the tip contact groove 1022 may have a stepped profile when viewed from the side. The tip contact groove 1022 may advantageously provide a margin of error and help ensure contact between the electrode 1020 and the underlying conductive core 1040. Any of the other microneedle variations described herein may also have similar tip contact grooves to help ensure contact between the electrode (which may be, for example, a working electrode, a reference electrode, a counter electrode, etc.) and the conductive pathway within the microneedle.

[0158] 11A and 11B illustrate additional various dimensions of exemplary variations of a pillar-shaped microneedle with a tapered distal portion and a ring electrode, similar to the microneedle 1000 described above. For example, the microneedle variations shown in FIGS. 11A and 11B may generally have a tapered distal portion with a taper angle of about 80 degrees (or about 78 degrees to about 82 degrees, or about 75 degrees to about 85 degrees) and a cone diameter of about 140 μm (or about 133 μm to about 147 μm, or about 130 μm to about 150 μm). The cone of the tapered distal portion may be arranged on the cylinder such that the overall combined height of the cone and cylinder is about 110 μm (or about 99 μm to about 116 μm, or about 95 μm to about 120 μm). The ring electrode on the tapered distal portion may have an outer or base diameter of about 106 μm (or about 95 μm to about 117 μm or about 90 μm to about 120 μm) and an inner diameter of about 33.2 μm (or about 30 μm to about 36 μm or about 25 μm to about 40 μm). The length of the ring electrode as measured along the slope of the tapered distal portion may be about 57 μm (or about 55 μm to about 65 μm), and the overall surface area of ​​the electrode may be about 12,700 μm.2 (or approximately 12,500 μm 2 ~Approx. 12,900μm 2 or approximately 12,000 μm 2 ~Approx. 13,000μm 2 ). As shown in FIG. 11B, the electrode may further have a tip contact groove extending around the periphery of the conical central region of the tapered distal portion, and the contact may have a width of about 11 μm (or about 5 μm to about 50 μm, about 10 μm to about 12 μm, or about 8 μm to about 14 μm) as measured along the slope of the tapered distal portion and a groove depth of about 1.5 μm (or about 0.1 μm to about 5 μm, or about 0.5 μm to about 1.5 μm, or about 1.4 μm to about 1.6 μm, or about 1 μm to about 2 μm). The microneedle has an insulated distal apex with a diameter of about 5.5 μm (or about 5.3 μm to about 5.8 μm, or about 5 μm to about 6 μm).

[0159] Details of exemplary variations of microneedle array configurations are described in further detail below.

[0160] As described above, each microneedle in the microneedle array may include an electrode. In some variations, multiple distinct types of electrodes may be included between the microneedles in the microneedle array. For example, in some variations, the microneedle array may function as an electrochemical cell capable of operating in an electrolytic mode with three types of electrodes. In other words, the microneedle array may include at least one working electrode, at least one counter electrode, and at least one reference electrode. Thus, the microneedle array may include three distinct electrode types, although one or more of each electrode type may form a complete system (e.g., the system may include multiple distinct working electrodes). Furthermore, multiple distinct microneedles may be electrically joined to form an effective electrode type (e.g., a single working electrode may be formed from two or more connected microneedles with working electrode sites). Each of these electrode types may include a metallization layer and one or more coatings or layers over the metallization layer that help facilitate the function of that electrode.

[0161] Generally, the working electrode is the electrode where the oxidation and / or reduction reaction of interest occurs for the detection of the analyte of interest. The counter electrode functions to source or sink (store) the electrons required to sustain the electrochemical reaction at the working electrode via current. The reference electrode functions to provide a reference potential for the system; i.e., the potential to which the working electrode is biased is referenced to the reference electrode. A fixed, time-varying, or at least controlled potential relationship is established between the working and reference electrodes, and, within practical limits, no current is sourced from or sunk to the reference electrode. In addition, to implement such a three-electrode system, the analyte monitoring device may include a suitable potentiostat or electrochemical analog front end to maintain a fixed potential relationship between the working and reference electrode components in the electrochemical system (via an electronic feedback mechanism) while allowing the counter electrode to dynamically swing to the potential required to sustain the redox reaction of interest.

[0162] Multiple microneedles (e.g., any of the microneedle variations described herein, each of which may have a working electrode, a counter electrode, or a reference electrode as described above) may be arranged in a microneedle array. Considerations for how to configure the microneedles include factors such as the desired insertion force for penetrating the skin with the microneedle array, optimization of electrode signal levels and other performance aspects, and manufacturing cost and complexity.

[0163] For example, a microneedle array may include multiple microneedles spaced at a predetermined pitch (the distance between the center of one microneedle and the center of its nearest neighboring microneedle). In some variations, the microneedles may be spaced with sufficient pitch to distribute the force applied to a user's skin to cause the microneedle array to penetrate the skin (e.g., avoid a "bed of needles" effect). As the pitch increases, the force required to insert the microneedle array tends to decrease and the depth of penetration tends to increase. However, it has been found that the pitch begins to affect the insertion force only at low values ​​(e.g., less than about 150 μm). Thus, in some variations, the microneedles in the microneedle array may have a pitch of at least 200 μm, at least 300 μm, at least 400 μm, at least 500 μm, at least 600 μm, at least 700 μm, or at least 750 μm. For example, the pitch may be about 200 μm to about 800 μm, about 300 μm to about 700 μm, or about 400 μm to about 600 μm. In some variations, the microneedles may be arranged in a periodic grid, and the pitch may be uniform in all directions and across all regions of the microneedle array. Alternatively, the pitch may vary as measured along different axes (e.g., X, Y directions), and / or some regions of the microneedle array may include a smaller pitch while others include a larger pitch.

[0164] Additionally, for more consistent penetration, the microneedles may be spaced equidistant from one another (e.g., the same pitch in all directions). To that end, in some variations, the microneedles in the microneedle array may be arranged in a hexagonal configuration, such as shown in Figures 12A-12C, 13A-13B, and 14A-14J. Alternatively, the microneedles in the microneedle array may be arranged in a rectangular array (e.g., a square array) or in another suitable symmetrical manner.

[0165] Another consideration for determining the configuration of a microneedle array is the overall signal level provided by the microneedles. Generally, the signal level at each microneedle is invariant to the total number of microneedle elements in the array. However, the signal level can be enhanced by electrically interconnecting multiple microneedles together in an array. For example, an array with a large number of electrically connected microneedles is expected to generate a signal strength (and therefore increased accuracy) greater than one with fewer microneedles. However, a larger number of microneedles on a die will increase die cost (assuming a constant pitch) and require more force and / or speed to insert into the skin. In contrast, a smaller number of microneedles on a die may reduce die cost and enable insertion into the skin with reduced application force and / or speed. Furthermore, in some variations, a smaller number of microneedles on a die may reduce the overall footprint of the die, which may lead to less unwanted localized edema and / or erythema. Thus, in some variations, a balance between these factors may be achieved using a microneedle array containing 37 microneedles as shown in Figures 13A-13B or a microneedle array containing 7 microneedles as shown in Figures 12A-12C. However, in other variations, there may be fewer microneedles in the array (e.g., about 5 to about 35, about 5 to about 30, about 5 to about 25, about 5 to about 20, about 5 to about 15, about 5 to about 100, about 10 to about 30, about 15 to about 25, etc.) or more microneedles in the array (e.g., greater than 37, greater than 40, greater than 45, etc.).

[0166] Additionally, as described in more detail below, in some variations, only a subset of the microneedles in the microneedle array may be active during operation of the analyte monitoring device. For example, some of the microneedles in the microneedle array may be inactive (e.g., no signal is read from the electrodes of the inactive microneedles). In some variations, some of the microneedles in the microneedle array may be activated at some point during operation and remain active for the remainder of the operational life of the device. Furthermore, in some variations, some of the microneedles in the microneedle array may additionally or alternatively be deactivated at some point during operation and remain inactive for the remainder of the operational life of the device.

[0167] When considering die characteristics for a microneedle array, die size is a function of the number of microneedles in the microneedle array and the pitch of the microneedles. Manufacturing cost is also a consideration, as a smaller die size will increase the number of dies that can be formed from a single wafer of a given area, contributing to lower costs. Furthermore, a smaller die size will also be less susceptible to brittle fracture due to the relative fragility of the substrate.

[0168] Furthermore, in some variations, microneedles at the periphery of the microneedle array (e.g., near the edge or boundary of the die, near the edge or boundary of the housing, near the edge or boundary of the adhesive layer on the housing, along the outer edge of the microneedle array, etc.) may be found to have better performance (e.g., sensitivity) due to better penetration compared to microneedles at the center of the microneedle array or die. Thus, in some variations, the working electrode may be arranged mostly or entirely on microneedles located at the periphery of the microneedle array to obtain more accurate and / or precise analyte measurements.

[0169] 13A and 13B depict illustrative schematic diagrams of 37 microneedles arranged in an exemplary variation of a microneedle array 1300. The 37 microneedles may be arranged in a hexagonal array, for example, with a center-to-center pitch between needles of about 750 μm (or about 700 μm to about 800 μm, or about 725 μm to about 775 μm) between the center of each microneedle and the center of its immediate neighbor in any direction. FIG. 13A depicts an illustrative schematic diagram of an exemplary variation of a die containing the microneedle array. Exemplary dimensions of the die (e.g., about 4.4 mm by about 5.0 mm) and the microneedle array 1300 are shown in FIG. 13B.

[0170] 12A and 12B depict perspective views of an illustrative schematic of seven microneedles 1210 arranged in an exemplary variation of microneedle array 1200. The seven microneedles 1210 are arranged in a hexagonal array on a substrate 1202. As shown in FIG. 12A, electrodes 1220 are arranged on distal portions of the microneedles 1210 extending from a first surface of the substrate 1202. As shown in FIG. 12B, proximal portions of the microneedles 1210 are conductively connected to respective backside electrical contacts 1230 on a second surface of the substrate 1202 opposite the first surface of the substrate 1202. FIGS. 12C and 12D depict top and side views of an illustrative schematic of a microneedle array similar to microneedle array 1200. As shown in Figures 12C and 12D, seven microneedles are arranged in a hexagonal array with a center-to-center pitch between each microneedle and the center of its immediate neighbor in any direction of about 750 µm. In other variations, the center-to-center pitch between needles may be, for example, about 700 µm to about 800 µm or about 725 µm to about 775 µm. The microneedles may have an approximate outer shaft diameter of about 170 µm (or about 150 µm to about 190 µm or about 125 µm to about 200 µm) and a height of about 500 µm (or about 475 µm to about 525 µm or about 450 µm to about 550 µm).

[0171] Additionally, the microneedle arrays described herein may have a high degree of configurability regarding where the working, counter, and reference electrodes are located within the microneedle array, and this configurability may be facilitated by the electronics system.

[0172] In some variations, the microneedle array includes electrodes distributed symmetrically or asymmetrically across two or more groups in the microneedle array, with each group featuring the same or different numbers of electrode components, depending on requirements for signal sensitivity and / or redundancy. For example, the same type of electrodes (e.g., working electrodes) may be distributed bilaterally or radially symmetrically across the microneedle array. For example, FIG. 14A depicts a variation of a microneedle array 1400A including two symmetric groups of seven working electrodes (WE), with the two working electrode groups labeled "1" and "2." In this variation, the two working electrode groups are distributed bilaterally symmetrically within the microneedle array. The working electrodes are generally arranged between a central region of three reference electrodes (RE) and an outer peripheral region of 20 counter electrodes (CE). In some variations, each of the two working electrode groups may include seven working electrodes electrically connected among themselves (e.g., to enhance the sensor signal). Alternatively, only a portion of one or both of the working electrode populations may include multiple electrodes that are electrically connected among themselves. As yet another alternative, the working electrode populations may include working electrodes that are stand-alone and not electrically connected to other working electrodes. Furthermore, in some variations, the working electrodes may be distributed in the microneedle array in an asymmetric or random configuration.

[0173] As another example, Figure 14B depicts a variation of microneedle array 1400B that includes four symmetric groups of three working electrodes (WE), labeled "1," "2," "3," and "4." In this variation, the four working electrode groups are distributed in a radially symmetric manner in the microneedle array. Each working electrode group is adjacent to one of two reference electrode (RE) components in the microneedle array, arranged in a symmetric manner. The microneedle array also includes counter electrodes (CE) arranged around the periphery of the microneedle array, except for two electrodes on the vertices of a hexagon, which may be inactive or used for other features or modes of operation.

[0174] In some variations, only a portion of the microneedle array may include active electrodes. For example, Figure 14C depicts a variation of a microneedle array 1400C with 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1," "2," "3," and "4") in a bilaterally symmetrical arrangement, 22 counter electrodes, and three reference electrodes. The remaining eight electrodes in the microneedle array are inactive. In the microneedle array shown in Figure 19C, each working electrode is surrounded by a group of counter electrodes. The two groups of such clusters of working and counter electrodes are separated by a row of three reference electrodes.

[0175] As another example, Figure 14D depicts a variation of microneedle array 1400D with 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1," "2," "3," and "4") in a bilaterally symmetrical arrangement, 20 counter electrodes, and three reference electrodes; the remaining 10 electrodes in the microneedle array are inactive.

[0176] As another example, Figure 14E depicts a variation of microneedle array 1400E with 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1," "2," "3," and "4"), 18 counter electrodes, and two reference electrodes. The remaining 13 electrodes in the microneedle array are inactive. The inactive electrodes are along a partial perimeter of the entire microneedle array, thereby reducing the effective size and shape of the active microneedle array to a smaller hexagonal array. Within the active microneedle array, the four working electrodes are generally arranged in a radially symmetrical fashion, with each working electrode surrounded by a group of counter electrodes.

[0177] Figure 14F depicts another exemplary variation of a microneedle array 1400F with 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1," "2," "3," and "4"), two counter electrodes, and one reference electrode. The remaining 30 electrodes in the microneedle array are inactive. The inactive electrodes are arranged in two layers around the periphery of the entire microneedle array, thereby reducing the effective size and shape of the active microneedle array to a smaller hexagonal array centered around the reference electrode. Within the active microneedle array, the four working electrodes are arranged bilaterally symmetrically, and the counter electrodes are equidistant from the central reference electrode.

[0178] Figure 14G depicts another exemplary variation of microneedle array 1400G with 37 microneedles and a reduced number of active electrodes. The active electrodes in microneedle array 1400G are arranged in a manner similar to that in microneedle array 1400F shown in Figure 14F, except that microneedle array 1400G includes one counter electrode and two counter electrodes, with a smaller hexagonal array of active microneedles centered around the counter electrode. Within the active microneedle array, the four working electrodes are arranged bilaterally symmetrically, and the reference electrode is equidistant from the central counter electrode.

[0179] Figure 14H depicts another exemplary variation of a microneedle array 1400H with seven microneedles. The microneedle array contains two microneedles (1 and 2) assigned as independent working electrodes, a counter electrode configuration consisting of four microneedles, and a single reference electrode. There is bilateral symmetry in the arrangement of working and counter electrodes, which are equidistant from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., on the periphery of the die or array) to take advantage of locations where the working electrodes are expected to have greater sensitivity and overall performance.

[0180] Figure 14I depicts another exemplary variation of a microneedle array 1400I with seven microneedles. The microneedle array contains four microneedles (1 and 2), each assigned as two independent groupings of two working electrodes, a counter electrode configuration consisting of two microneedles, and a single reference electrode. There is bilateral symmetry in the arrangement of working and counter electrodes, which are equidistant from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., on the periphery of the die or array) to take advantage of locations where the working electrodes are expected to have greater sensitivity and overall performance.

[0181] Figure 14J depicts another exemplary variation of a microneedle array 1400J with seven microneedles. The microneedle array contains four microneedles (1, 2, 3, and 4) assigned as independent working electrodes, a counter electrode configuration consisting of two microneedles, and a single reference electrode. There is bilateral symmetry in the arrangement of working and counter electrodes, which are equidistant from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., on the periphery of the die or array) to take advantage of locations where the working electrodes are expected to have greater sensitivity and overall performance.

[0182] While Figures 14A-14J illustrate exemplary variations of microneedle array configurations, it should be understood that these figures are not limiting and that other microneedle configurations (including different numbers and / or distributions of working, counter, and reference electrodes, and different numbers and / or distributions of active and inactive electrodes, etc.) may be suitable in other variations of microneedle arrays.

[0183] 1, in some variations, the analyte monitoring device 110 may be applied using a suitable applicator 160. The applicator may be configured, for example, to urge the analyte monitoring device 110 toward the user's skin such that the microneedle array 140 is inserted into the skin (e.g., to a desired target depth) and one or more adhesive layers adhere to the skin, holding the analyte monitoring device 110 securely in place.

[0184] The applicator may include an actuatable housing (also referred to as an actuator and / or housing) including a housing body defining a cavity therein. The housing body has a distal opening, and the applicator components may be mounted and / or positioned within the cavity of the housing body. The applicator components are aligned and configured to securely hold the analyte monitoring device 110 so that it is positioned for insertion of the microneedle array 140 into the skin (e.g., with the microneedle array positioned such that the microneedle tips are oriented distally). Furthermore, the applicator components are aligned and configured to move and release the analyte monitoring device 110 at a speed that allows the microneedles of the microneedle array 140 to be inserted into the skin with sufficient force.

[0185] In some variations, the applicator may include a housing body, a cuff assembly, a shuttle, and a removable base (also referred to as the base). The housing body, cuff assembly, shuttle, and base may be engaged with one another using one or more releasable coupling and / or engagement features. The base may be removed from engagement with the housing body to align and position the cuff assembly and shuttle in a configuration in which the analyte monitoring device 110, held by the shuttle, is ready for insertion into the skin. The shuttle and cuff assembly are independently translatable relative to the housing body. In an application procedure, actuation of the housing body (e.g., manually by a user or with an additional external actuator) moves the shuttle and analyte monitoring device 110 at a speed that allows the microneedle array 140 to be inserted into the user's skin with a force that inserts the microneedles of the microneedle array 140 into the skin.

[0186] The housing, cuff assembly, and shuttle may be axially aligned (e.g., concentrically) and / or nested together and / or telescopically arranged. The shuttle may releasably retain (e.g., grasp, embrace, or otherwise carry) the analyte monitoring device 110. The applicator may transition from a first "collapsed" configuration to a second "extended" configuration to a third "released" configuration. In the collapsed configuration, the components of the applicator are locked relative to one another such that engagement between the various components of the applicator is fixed, the components cannot move relative to one another, and the analyte monitoring device 110 cannot be deployed. In the collapsed configuration, the base is engaged with the housing. In the extended configuration, the components of the applicator are arranged and configured such that the analyte monitoring device can be deployed (e.g., released) from the applicator in response to actuation of the housing. The base is removed, and the shuttle is moved to a fired position in the extended configuration. In the released configuration, the analyte monitoring device 110 is released from the applicator and inserted into the user's skin. Each configuration and the transitions between them are described in detail below.

[0187] The cuff assembly may be a single component, or in some variations, two or more components may be incorporated to form the cuff assembly. For example, the cuff and friction ring may engage and / or lock together as further described herein.

[0188] In some variations, in the collapsed configuration, the analyte monitoring device 110 is retained within the shuttle and the distal edge of the shuttle and cuff are in their proximal-most positions. In the extended configuration, the distal edge of the cuff is in its distal-most position and the shuttle is in its intermediate position. In the released configuration, the analyte monitoring device 110 is released from the shuttle, the distal edge of the cuff is in its intermediate position and the shuttle is in its distal-most position.

[0189] The housing may include a first retaining surface or feature that is releasably coupled with a coupling member of the cuff assembly. The housing may also include a second retaining surface or feature that is releasably engaged with an engagement member of the shuttle. In response to actuation of at least a portion of the housing toward the shuttle (e.g., the applicator may be placed in compression against a user's skin surface, etc.), the first retaining surface of the housing may disengage from the coupling member of the cuff assembly, which may allow for release of engagement between the second retaining surface of the housing and the engagement member of the shuttle. During axial movement of the shuttle, in response to actuation of the housing, the shuttle may engage at least one shuttle flexing surface (e.g., a positive stop) of the cuff assembly. Engagement of the shuttle and the shuttle flexing surface may cause a radial outward deflection of the shuttle, resulting in release of the analyte monitoring device 110 from the shuttle.

[0190] Further, the applicator may include one or more biasing elements (e.g., springs) arranged to urge adjacent components apart. For example, in some variations, the applicator may include a first biasing element arranged between the housing and the cuff assembly. The first biasing element may be loaded to store potential energy prior to actuation of the housing (e.g., the first biasing element may include a compression spring that is pre-compressed prior to actuation of the housing). During the application procedure, in response to actuation of the housing, the first biasing element may provide a force to the cuff assembly that disengages the first retention surface of the housing from the coupling member of the cuff assembly. Additionally or alternatively, the applicator may include a second biasing element arranged between the housing and the shuttle. The second biasing element may be loaded to store potential energy prior to actuation of the housing (e.g., the second biasing element may include a compression spring that is pre-compressed prior to actuation of the housing). Upon actuation of the housing, when the shuttle disengages from the housing during the application procedure, energy stored in the loaded second biasing element can be transferred to the shuttle, thereby driving the analyte monitoring device with a suitable applied force (e.g., for suitable skin puncture with the microneedle array). The incorporation of two biasing elements for deployment of the analyte monitoring device 110 allows for control of the actuation force and velocity (e.g., impact velocity) at which the shuttle moves in response to actuation of the housing. The dual biasing element design allows for control of the impact velocity independent of the force applied for actuation. In some variations, the force on the cuff assembly provided by the first biasing element may range from about 5 Newtons to about 45 Newtons. In some variations, the residual force provided to the shuttle by the second biasing element may range from about 5 Newtons to about 45 Newtons. The impact velocity may range from about 2 meters / second to about 10 meters / second. The force provided by the first and second biasing elements and the resulting impact velocity may be controlled by adjusting the compression and properties of the biasing elements.

[0191] The components of the applicator may be formed using any suitable manufacturing process, including injection molding, casting, 3D printing, machining techniques (e.g., using rolling or lathing), and / or the like.

[0192] 15A-15D depict an exemplary variation of an applicator 1500 for an analyte monitoring device (e.g., analyte monitoring device 110). FIGS. 15A and 15B are side views, FIG. 15C is a top perspective view, and FIG. 15D is a bottom perspective view of applicator 1500. FIGS. 15A and 15B depict applicator 1500 in a collapsed configuration in which base 1550 is engaged with a housing covered by outer enclosure 1570.

[0193] 15C and 15D depict exploded views of applicator 1500. As shown in FIGS. 15C and 15D, applicator 1500 includes a housing 1510, a cuff 1520, a friction ring 1530, a shuttle 1540, and a base 1550. Housing 1510 includes a housing body defining a cavity therein. Housing body has a distal opening through which components of the applicator may be mounted and / or positioned within and / or connected to the cavity of the housing body.

[0194] The friction ring 1530 is configured to be axially aligned with, nested within, and arranged (e.g., telescopically arranged) with the cuff 1520. The cuff 1520 and friction ring 1530 are configured to be axially aligned with, nested within, and arranged with the housing body cavity. The shuttle 1540 is configured to be axially aligned with, nested within, and arranged with the nested arrangement of the cuff 1520 and friction ring 1530 within the housing body cavity.

[0195] The applicator 1500 also includes a base 1550 arranged to engage the housing body at its distal opening. A locking member 1560, an outer enclosure 1570, and an upper plug 1580 are also provided. In some variations, the outer enclosure 1570 and / or the upper plug 1580 are optional and need not be included within the applicator 1500 for operation.

[0196] As further shown in Figures 15C and 15D, a first biasing element 1582 (e.g., a first compression spring) may be arranged between the housing 1510 and the cuff 1520, and a second biasing element 1584 (e.g., a second compression spring) may be arranged between the housing 1510 and the shuttle 1540.

[0197] 15E and 15F depict a side view of the shuttle 1540 and the analyte monitoring device 110 relative to one another in exploded and perspective views, respectively. As shown in FIGS. 15E and 15F, the analyte monitoring device 110, along with the attached microneedle enclosure 500, may be retained within the shuttle 1540 with the microneedle array 140 (enclosed by the microneedle enclosure 500 in the views of FIGS. 15E and 15F) in the distal direction. When the shuttle 1540 is arranged within the cavity of the housing body, the analyte monitoring device 110 is at the distal end.

[0198] The base 1550 is removably coupled to the housing body and completely encloses the analyte monitoring device 110 within a cavity defined by the housing body (e.g., to preserve the sterility of the device 110 prior to application, as further described herein). The base 1550 is a removable distal cover or cap that is releasably engaged with the housing body when the applicator is in a collapsed configuration. The base 1550 couples to a microneedle enclosure 500, which provides a sterile environment for the microneedle array 140. In some variations, when the base 1550 is removed from the housing body, the microneedle enclosure 500 is removed along with the base 1550, thereby making the microneedle array 140 accessible through a distal opening in the housing body. Additional details are provided herein.

[0199] 16A, 16B, 16C, and 16D depict a side view of shuttle 1540 in further detail. FIG. 16A is a perspective view of shuttle 1540, FIG. 16B is a bottom view, FIG. 16C is a side view, and FIG. 16D is a cross-sectional side view taken along line AA shown in FIG. 16C. Shuttle 1540 is configured to retain analyte monitoring device 110 when applicator 1500 is in the collapsed and extended configuration. Shuttle 1540 is configured to deploy analyte monitoring device 110 in response to actuation of housing 1510 with the speed and force required to insert microneedles of microneedle array 140 into the user's skin. In the applicator's release configuration, analyte monitoring device 110 is released from shuttle 1540.

[0200] As shown, the shuttle 1540 includes a base portion 1610 and a shuttle shaft 1630. The shuttle shaft 1630 defines an internal cavity 1632 in which the second biasing element 1584 is arranged.

[0201] The shuttle 1540 may include an engagement member or feature for releasably engaging with a shuttle retaining surface or feature of the housing 1510. The engagement member or feature may be formed around one or more portions of the circumference of the shuttle shaft 1630 and may be configured to releasably engage with a shuttle retaining surface of the housing 1510. In some variations, as best seen in FIG. 16C , the engagement member may include a distal surface 1636 of a ledge 1634. The ledge 1634 may be a section of the shuttle shaft 1630 that extends horizontally outward from the shuttle shaft 1630. The span (e.g., width or diameter) of the ledge 1634 is greater than the span (e.g., width or diameter) of the shuttle shaft 1630, the span being measured in a direction perpendicular to the axial alignment of the shuttle 1540 within the cavity of the housing body. The distal surface 1636 may be a surface, such as a step, extending between the ledge 1634 and the shuttle shaft 1630. In some variations, the distal surface 1636 may be an angled surface. In some variations, the distal surface 1636 may be flat or generally flat. As described further herein, the distal surface 1636 releasably engages the housing 1510 at a shuttle retention surface.

[0202] The base portion 1610 includes, at the distal end of the shuttle shaft 1630, one or more flexible leaves 1612 extending from the shuttle shaft 1630, one or more flexible support petals 1614 extending from the shuttle shaft 1630, and one or more following protrusions 1616 extending from the outer walls of the one or more flexible leaves 1612.

[0203] The configuration or orientation of the flexible leaves 1612 defines the configuration (e.g., delivery configuration and release configuration) of the shuttle 1540, as described further herein. The flexible leaves 1612 define a receptacle 1640 within which the analyte monitoring device 110 can be received. For example, as shown in FIGS. 16A and 16B , each flexible leaf 1612 includes an arcuate or curved member extending at its proximal end from a flexible connecting member that is attached to the shuttle shaft 1630. The flexible connecting member allows the flexible leaf 1612 to flex relative to the shuttle shaft 1630. For example, the flexible leaves 1612, in some variations, are cantilevered arms that can flex radially outward. The flexible leaves 1612 may be arranged circumferentially around the shuttle shaft 1630 and define a receptacle 1640 that approximates the footprint of the analyte monitoring device 110 for embracing the analyte monitoring device 110. As shown in FIGS. 16A and 16B , the receptacle 1640 may be generally circular. The shuttle 1540 is in a transport configuration in which the analyte monitoring device 110 is embraced or retained within the receptacle 1640 when the flexible leaves 1612 are in their natural, unflexed state. In the transport configuration, the analyte monitoring device 110 is held within the receptacle 1640 due to engagement between the inner walls of the flexible leaves 1612 and the periphery of the analyte monitoring device 110. External pressure may be applied to the flexible leaves 1612, for example, to transition the shuttle 1540 to the released configuration. In the released configuration, the analyte monitoring device 110 is not held by the flexible leaves 1612 and the analyte monitoring device 110 can be released from the receptacle 1640. External pressure may be provided, at least in part, by the second biasing element 1584. For example, during an application procedure, in response to actuation of the housing 1510, the shuttle 1540 is moved axially downward through a concentric (e.g., retractable) arrangement within the cuff 1520 and the second biasing element 1584 is compressed within the inner cavity 1632. A tracking protrusion 1616 extending from the outer wall of the flexible leaves 1612 of the shuttle 1540 engages and interferes with a shuttle flexing surface (e.g., a positive stop) of the cuff 1520 during axial movement of the shuttle 1540.The shuttle flexing surface of the cuff 1520 stops the axial movement of the shuttle 1540, and energy stored in the second biasing element 1584 is transferred to the shuttle 1540, thereby flexing the flexible leaves 1612 radially outward to eject the analyte monitoring device 110 with a suitable applied force (e.g., for suitable insertion of the microneedle array 140 into the user's skin). The configuration of the flexible leaves 1612 is similar and / or analogous to a collet configuration, where in the delivery configuration the collet arms are biased radially inward to engage and retain a component. At the end of the delivery path, the collet arms are released from their biased state, thereby disengaging the component.

[0204] In some variations, each flexible leaf 1612 may further include one or more optional attachment features arranged at the distal end of the flexible leaf 1612 and configured to assist in embracing the analyte monitoring device 110. For example, as shown in Figures 16B and 16D, at least one flexible leaf 1612 may include a shoulder 1622 or other protrusion or stepped support surface at the distal end of the arcuate or curved member of the flexible leaf 1612. The shoulder 1622 or other protrusion or stepped support surface may extend inward at the distal end and help to provide stable support for the distal surface of the analyte monitoring device 110.

[0205] In some variations, each flexible support petal 1614 is a tab-like member extending from a flexible connecting member that is attached at its proximal end to the shuttle shaft 1630. The flexible support petals 1614 may be arranged circumferentially around the shuttle shaft 1630 in an alternating configuration with the flexible leaves 1612. The flexible support petals 1614 may each have a radiused or curved distal surface to retain and / or support and / or stabilize the proximal surface of the analyte monitoring device 110. For example, in some variations, a portion of the proximal surface of the analyte monitoring device 110 fits snugly within the radiused configuration formed by the distal surfaces of the flexible support petals 1614.

[0206] Each flexible support petal 1614 may also include one or more optional binding or gripping features. For example, a support gripper 1624 in the form of a protrusion or extension of a tab-like member may be positioned at the distal end of one or more of the flexible support petals 1614. The support gripper 1624, together with the radiused or curved distal surface of the flexible support petal 1614, helps to stabilize and hold the analyte monitoring device 110.

[0207] When the analyte monitoring device 110 is installed within the receptacle 1640, the shoulders 1622 and / or gripping members 1624 provide additional support for holding or retaining the analyte monitoring device 110. The engagement between the circumferential edge of the analyte monitoring device 110 and the shoulders 1622 and / or the engagement between the proximal surface of the analyte monitoring device 110 and the gripping members 1624 helps to provide additional stability of the analyte monitoring device 110 within the receptacle 1640 when the shuttle 1540 is in the transport configuration. When the flexible leaves 1612 are flexed radially outward (in the release configuration of the shuttle 1540), the shoulders 1622 do not engage the analyte monitoring device 110 and therefore do not provide additional stability and / or impede the release of the analyte monitoring device 110.

[0208] Although the shuttle 1540 is shown with four flexible leaves 1612 and four flexible support petals 1614, in other variations, the shuttle 1540 may have any suitable number (e.g., 1, 2, 3, 5, 6, or more) of flexible leaves 1612 and any suitable number (e.g., 1, 2, 3, 5, 6, or more) of flexible support petals 1614. In some variations, no flexible support petals 1614 are included. In some variations, the number of flexible leaves 1612 may vary from the number of flexible support petals 1614. For example, the shuttle 1540 may include fewer or more flexible support petals 1614 than flexible leaves 1612.

[0209] Although the shuttle 1540 is shown with flexible leaves 1612 that are substantially equal in size and shape to one another, in other variations, one or more of the flexible leaves 1612 may vary in size and shape from one or more of the other flexible leaves 1612. For example, the shuttle 1540 may include two flexible leaves 1612 that have a longer circumference than the two other flexible leaves 1612. Similarly, although the shuttle 1540 is shown with flexible support petals 1614 that are substantially equal in size and shape to one another, in other variations, one or more of the flexible support petals 1614 may vary in size and shape from one or more of the other flexible support petals 1614.

[0210] Although the receptacle 1640 is shown as having a rounded or substantially rounded footprint formed by the shape and configuration of the flexible leaves 1612 and flexible support petals 1614, the receptacle 1640 may define a footprint of other shapes, such as square, oval, rectangular, etc., to account for the shape of the analyte monitoring device 110. The flexible leaves 1612 and flexible support petals 1614 may have varying configurations (e.g., curvature, size, shape, etc.) to provide retention and release of analyte monitoring devices of any shape. In some variations, the curvature of the flexible support petals 1614 mirrors the curvature of the proximal surface of the analyte monitoring device such that the flexible support petals 1614 embrace the proximal surface.

[0211] 16E and 16F, additional features of the shuttle 1540 are illustrated in bottom perspective and bottom plan views, respectively. In some variations, a gripping layer 1650 may be provided on the distal surfaces of the flexible leaves 1612, flexible support petals 1614, and shuttle shaft 1630. The gripping layer 1650 may be an elastomeric layer deposited and / or applied to provide additional gripping capabilities between the analyte monitoring device 110 and the flexible leaves 1612, flexible support petals 1614, and / or the distal surface of the shuttle shaft 1630. In some variations, one or more proximal surfaces of the analyte monitoring device 110 may be smooth or substantially smooth, and the incorporation of the gripping layer 1650 helps to retain the analyte monitoring device 110 within the receptacle 1640 defined by the flexible leaves 1612. In some variations, a gripping layer 1650 is provided on one or more distal surfaces of the flexible leaf 1612, flexible support petal 1614, and / or shuttle shaft 1630 that contact the analyte monitoring device 110 when retained within the receptacle 1640. In some variations, the gripping layer 1650 is uniformly distributed. In some variations, the gripping layer 1650 is non-uniformly distributed. In some variations, the gripping layer 1650 is provided at one or more points of contact between the analyte monitoring device 110 and the distal surface of the flexible leaf 1612, flexible support petal 1614, and / or shuttle shaft 1630.

[0212] 16G and 16H depict, in side and side cross-sectional views, respectively, a side view of shuttle 1540 with modifications to shelf 1634. Additional aspects and features of shuttle 1540 may be the same as those shown and described with reference to FIGS. 16A-16F.

[0213] In some variations, the ledge 1634 has a proximal surface 1638. The proximal surface 1638 may be a surface, such as a step, extending between the ledge 1634 and the shuttle shaft 1630. In some variations, the proximal surface 1638 may be an angled surface. In some variations, the proximal surface 1638 may be flat or generally flat. The proximal surface 1638 of the ledge 1634 may, in some variations, be used as a shuttle arresting feature. For example, it may be desirable to incorporate a feature that prevents the shuttle 1540 from being reloaded such that the applicator 1500 cannot be moved from the released configuration to the extended configuration. This may be desirable in situations in which the sterility state and / or condition of the analyte monitoring device 110 is unknown. For example, when the analyte monitoring device 110 is released from the applicator 1500, the microneedle array 140 or other components of the analyte monitoring device 110 may be compromised. In response to axial movement of the shuttle 1540 toward the proximal end of the housing 1510, after disengagement of the housing 1510 at the distal surface 1636 of the shuttle 1540 and the shuttle retaining surface, the axial movement of the shuttle 1540 is stopped by the distal end of the shuttle retaining surface. In particular, the proximal surface 1638 will abut against the distal end of the shuttle retaining surface and prevent axial movement of the shuttle 1540 toward the proximal end of the housing 1510. The distal end of the shuttle retaining surface may be a flat or nearly flat surface to prevent the proximal surface 1638 from being pushed past the shuttle retaining surface.

[0214] In some variations (such as those shown in and described with reference to FIGS. 16A-16D ), the applicator 1500 may be rechargeable and / or reusable. For example, the shuttle 1540 is rechargeable, allowing axial movement of the shuttle 1540 toward the proximal end of the housing 1510, such that the applicator components are reengaged in an extended configuration.

[0215] In some variations, alternative and / or additional shuttle restraining features may be incorporated. In one variation, spring finger features are nested within the shuttle shaft 1630 within retention posts positioned within the shuttle shaft 1630. The distal ends of the spring-loaded fingers are flexed inward and held by the retention posts. The proximal ends of the spring-loaded fingers are held at the proximal end of the cavity in the housing body. As the applicator 1500 transitions to the extended configuration and the shuttle 1540 moves toward the distal end of the housing body, the retention posts also move with the shuttle 1540, and the spring-loaded fingers expand to a larger radial configuration. In the larger radial configuration, the spring-loaded fingers create a blocking surface for the shuttle 1540 if a shuttle reload or repositioning (e.g., moving the shuttle 1540 toward the proximal end of the housing body) is attempted.

[0216] In another variation, a restraining post is positioned within the shuttle shaft 1630. The restraining post includes a spring-loaded finger at its distal end that engages with an interior surface feature of the shuttle shaft 1630. At its proximal end, the restraining post is engaged within a footprint defined by a restraining arm extending from the proximal end of the cavity in the housing body. Engagement of the restraining post within the footprint defined by the restraining arm causes outward deflection of the restraining arm. As the applicator 1500 transitions to the extended configuration and the shuttle 1540 moves toward the distal end of the housing body, the restraining post moves with the shuttle 1540, and the restraining arm deflects inward toward its natural, unflexed state. The distal end of the restraining arm provides a blocking surface for the shuttle 1540 when shuttle reloading or repositioning is attempted.

[0217] 17A-17E depict in further detail the side view of cuff 1520. Fig. 17A provides a top perspective view of cuff 1520, Fig. 17B is a bottom view, Fig. 17C is a top view, Fig. 17D is a first side and corresponding side cross-sectional view, and Fig. 17E is a second side and corresponding side cross-sectional view.

[0218] The cuff 1520 is arranged within a cavity defined by the housing body and is configured to maintain the applicator 1500 in a collapsed configuration (in which the positions of the housing 1510 and the shuttle 1540 are fixed relative to one another) when the base 1550 is engaged with the housing 1510. The cuff 1520 is further configured to disengage the base 1550 from the housing 1510 and transition the applicator 1500 to an extended configuration in response to depression of the locking member 1560. The cuff 1520 interacts with and engages with the friction ring 1530, as further described herein, to transition the shuttle 1540 to a firing position in the extended configuration. The shuttle 1540 may be substantially axially aligned and nested within the cuff 1520, and the shuttle 1540 may move axially within the cuff 1520. The cuff 1520 functions to cause the analyte monitoring device 110 to disengage from the shuttle 1540 in response to actuation of the housing 1510 .

[0219] 17A, the cuff 1520 is a tubular structure with a sidewall and a lumen 1720 extending therethrough. The cuff 1520 has a proximal opening and a distal opening. The firing ring 1530 and shuttle 1540 are axially aligned and move axially within the lumen 1720 through the proximal and / or distal openings.

[0220] In some variations, the cuff 1520 is generally cylindrical with a circular or approximately circular cross-section along a plane perpendicular to the height of the cuff 1520. In some variations, the cuff 1520 may have other configurations. For example, the cuff 1520 may have a square, rectangular, or oval cross-section. The effective inner diameter or inner span between opposing side walls may be consistent along the height of the cuff 1520. In some variations, the effective inner diameter or inner span of the cuff 1520 may vary slightly along its height. The upper shoulder 1722 is positioned at the proximal end of the cuff 1520 along the proximal opening, and the bottom flange 1732 is positioned at the distal end of the cuff 1520 along the distal opening.

[0221] The cuff 1520 includes a retaining wall 1712 formed on the outer wall and extending generally along the height of the cuff 1520 at a location corresponding to a respective one of the locking members 1560. As shown, in some variations, the cuff 1520 has two retaining walls 1712 corresponding to the two locking members 1560. In some variations, the cuff 1520 has fewer or additional retaining walls 1712 and corresponding locking members 1560. For example, in some variations, there may be one retaining wall 1712 and one locking member 1560. Each retaining wall 1712 is defined by a retaining edge 1714 that extends around at least a portion of the circumference of the retaining wall 1712. Each retaining wall 1712 may be sized and shaped to generally correspond to the outer periphery of the movable locking member 1560 such that the retaining edge 1714 closely conforms to and / or aligns with the outer periphery of the movable locking member 1560. The outer exposed surface of the retaining wall 1712 may be flat or substantially flat. In some variations, the outer curvature of the cuff 1520 forms the outer exposed surface of the retaining wall 1712.

[0222] An upper edge of the retaining lip 1714 is configured to engage an upper edge of a corresponding locking member 1560. In the collapsed configuration of the applicator 1500, the locking member 1560 is positioned within the retaining wall 1712 such that the upper edge of the locking member 1560 is engaged beneath the upper edge of the retaining lip 1714, preventing downward movement of the cuff 1520 relative to the housing 1510. Upon depression of the locking member 1560, vertical movement of the cuff 1520 is no longer impeded due to the locking member 1560 being removed from engagement with the upper edge of the retaining lip 1714. Additional details are further described herein.

[0223] The rotational alignment of the shuttle 1540 within the cuff 1520 may be guided by one or more track features. The one or more track features may also guide the axial movement of the shuttle 1540 within the cuff 1520. For example, the cuff 1520 may include one or more tracks 1716 extending along at least a portion of the height of the cuff 1520, within which one or more tracking protrusions 1616 on the shuttle 1540 may travel. The track 1716 may include an open slot, as shown in FIG. 17A , or other suitable structure (e.g., a recessed groove or channel) with which the tracking protrusions 1616 on the shuttle 1540 may slidably engage. The track 1716 may also be configured to receive other suitable types of track features (e.g., ball bearings) on the shuttle 1540. The cuff 1520 and shuttle 1540 may include any suitable number of track features (e.g., one, two, three, four, or more), and the track features may be circumferentially distributed in an equal or unequal manner. For example, four track features may be equally distributed around the circumference of the shuttle 1540 and cuff 1520 so that they are 90 degrees apart from each other. In some variations, two track features may be equally distributed so that they are 180 degrees apart from each other or directly opposite each other, three track features may be equally distributed so that they are 120 degrees apart from each other, etc.

[0224] Each track 1716 may terminate at a shuttle flex surface 1718 at the bottom end of the track 1716. The shuttle flex surface 1718 may be part of the bottom surface or bottom flange 1732 of the cuff 1520 or another stepped surface that acts as a stop for axial movement of the shuttle 1540 and assists in radially outward deflection of the flexible leaves 1612 of the shuttle 1540. For example, the shuttle flex surface 1718 of each track 1716 prevents further movement of the shuttle 1540 beyond the bottom edge of the cuff 1520.

[0225] The upper shoulder 1722 of the cuff 1520 may include features for engaging and locking with the friction ring 1530. In the collapsed configuration of the applicator 1500, the friction ring 1530 is collapsed within the lumen 1720 of the cuff 1520. Upon transitioning from the collapsed configuration to the extended configuration, the friction ring 1530 retracts and / or extends out of the proximal opening of the cuff 1520 at its proximal end. The collapsed arrangement of the friction ring 1530 within the cuff 1520 in the collapsed configuration of the applicator 1500 provides a compact overall height for the applicator 1500. In some variations, the friction ring 1530 is not collapsed within the cuff 1520, resulting in an applicator having a greater height in the collapsed configuration. In some variations, the friction ring 1530 and the cuff 1520 are not separate components.

[0226] A step formed circumferentially around the upper edge of the cuff 1520 can ensure engagement of the friction ring 1530 and the cuff 1520. In some variations, a portion of the upper step 1722 can include a lower edge 1724 with a guide wall 1726. The lower edge 1724 can be a flat or substantially flat surface extending outward from a portion of the upper step 1722 such that the lower edge 1724 extends across a corresponding portion of the lumen 1720. Two guide walls 1726 can be arranged on either end of the lower edge 1724, where the guide walls 1726 include vertically extending members extending upward from or adjacent to the lower edge 1724. The lower edge 1724 provides a flat surface for engaging the flexible tab of the friction ring 1530, and the pair of guide walls 1726 secure the flexible tab onto the lower edge 1724 by preventing rotational movement of the friction ring 1530. For example, the pair of guide walls 1726 are positioned at opposite ends of the lower edge 1724 to lock the flexible tab in place on the lower edge 1724. The cuff 1520 may include more than one of the engagement and locking features to ensure engagement with the friction ring 1530, and the engagement and locking features may be distributed circumferentially around the upper step 1722 in an equal or unequal manner. For example, as shown in FIGS. 17A, 17B, and 17C, three lower edges 1724 with corresponding pairs of guide walls 1726 are equally distributed around the upper step 1722, 120 degrees apart from each other. In some variations, four lower edges 1724 with corresponding pairs of guide walls 1726 may be equally distributed so that they are 90 degrees apart from each other, two lower edges 1724 with corresponding pairs of guide walls 1726 may be equally distributed so that they are 180 degrees apart from each other or directly opposite each other, etc.

[0227] The lower surface 1728 of the upper step 1722 may also interface with the friction ring 1530. For example, the lower surface 1728 may interface with a portion of the circumferential edge of the friction ring 1530, and the friction ring 1530 may be used to maintain the axial position of the cuff 1520. Additional details related to engagement and locking are further described herein.

[0228] The outer wall of the cuff 1520 may have features for interfacing with the base 1550. For example, a base retention surface 1730 may be formed on one or more portions around the periphery and near or at the distal end of the cuff 1520. The base retention surface 1730 may be a rib that protrudes from the outer wall of the cuff 1520 and may be configured to provide a retention surface for one or more members of the base 1550, as described further herein.

[0229] 17F and 17G depict, in bottom and side views, respectively, a side view of the cuff 1520 with modifications to the bottom flange 1732. Additional aspects and features of the cuff 1520 may be the same as those shown in and described with reference to FIGS. 17A-17E. As shown in FIGS. 17F and 17G, the bottom flange 1732 has an increased surface area compared to the bottom flange shown, for example, in FIGS. 17A-17C. During actuation of the applicator 1500, the distal end of the bottom flange 1732 provides the contact area with the user's skin at the insertion site for the analyte monitoring device 110. The increased surface area of ​​the bottom flange 1732 distributes the force applied during actuation, making the application process a more comfortable experience for the user. With a bottom flange (e.g., 17A-17C) having a smaller surface area, the force applied during actuation is concentrated over a smaller area, resulting in a more noticeable force felt by the user at the distal end of the cuff 1520.

[0230] The bottom flange 1732, which has an increased surface area, has cutouts 1734 formed therethrough to accommodate the arms of the base 1550, as described further herein.

[0231] The bottom flange 1732 creates a contact surface area for insertion of the microneedle array 140 of the analyte monitoring device 110. The contact surface area, along with the actuation force required to actuate the housing body, causes the user's skin to bulge convexly inside the perimeter of the bottom flange 1732 distal to the microneedle array 140 when the applicator 1500 is in the extended configuration. As the skin bulges (in some variations, approximately 3-6 mm, depending on skin type), it stretches and tightens, providing a preferred insertion site for microneedle array insertion because the stretched / tightened skin improves insertion effectiveness and consistency. The domed and convex shape of the skin reduces the well-known "bed of needles" effect that can occur with standard microneedle insertion. The result is that microneedles at the center of the microneedle array penetrate first, followed by microneedles around the perimeter of the microneedle array, resulting in consistent and effective insertion.

[0232] 18A-18D depict in further detail a side view of friction ring 1530. Fig. 18A provides a first top perspective view of friction ring 1530, Fig. 18B is a second top perspective view, Fig. 18C is a first bottom perspective view, and Fig. 18D is a second bottom perspective view.

[0233] The frictional ring 1530 has a ring-shaped structure that is concentrically and axially arranged within the cuff 1520 and serves as an extension of the cuff 1520 for application of the analyte monitoring device 110. In the collapsed configuration of the applicator 1500, the frictional ring 1530 is collapsed within the cuff 1520. The frictional ring 1530 includes a coupling member that prevents the launch of the shuttle 1540 until the base 1550 is removed. During the transition of the applicator 1500 from the collapsed configuration to the extended configuration, in response to the removal of the base 1550, the cuff 1520 moves axially toward the distal opening of the housing body such that the frictional ring 1530 extends and / or stretches out from the proximal opening and locks into the cuff 1520. During actuation of the housing 1510, the frictional ring 1530 and the cuff 1520 lock together as a single component and function to cause disengagement of the analyte monitoring device 110 from the shuttle 1540. The shuttle 1540 may be substantially axially aligned and nested within the frictional ring 1530, and the shuttle 1540 may move axially within the frictional ring 1530.

[0234] 18A-18D, friction ring 1530 has a ring-shaped core defining a friction ring cavity 1810 extending therethrough. Shuttle 1540 is axially aligned and moves within friction ring cavity 1810. An outer wall of the ring-shaped core is axially aligned and moves within cuff 1520 and extends at least partially outward therefrom.

[0235] Locking of the cuff 1520 and the frictional ring 1530 may be achieved by one or more engaging and locking features. For example, the frictional ring 1530 may include one or more features that engage and lock with individual features of the cuff 1520. In some variations, the engaging and locking features may be arranged circumferentially around the ring-shaped core of the frictional ring 1530. For example, the flexible tab 1812 may extend along at least a portion of the height of the outer wall of the ring-shaped core and be circumferentially aligned with the lower edge 1724 of the cuff 1520. A proximal or top end of the flexible tab 1812 is attached or secured to the top shoulder 1814 of the frictional ring 1530, and a distal or bottom end of the flexible tab 1812 is unsecured, allowing the distal end of the flexible tab 1812 to flex or move relative to the secured proximal end. When the applicator 1500 is in the collapsed configuration, the proximal end of the flexible tab 1812 is aligned with a portion of the inner diameter of the upper shoulder 1722 of the cuff 1520. During the transition of the applicator 1500 from the collapsed configuration to the extended configuration, the cuff 1520 moves axially along the length of the flexible tab 1812, relative to the friction ring 1530, toward and through the distal opening of the housing body. The flexible tab 1812 is flexed or pushed inward until the cuff 1520 passes the distal end of the flexible tab 1812, at which point the flexible tab 1812 snaps onto the lower edge 1724 and is held between a pair of guide walls 1726.

[0236] The friction ring 1530 may include more than one flexible tab 1812, and the flexible tabs 1812 may be distributed circumferentially around the outer wall of the ring-shaped core in an equal or unequal manner. For example, as shown in FIGS. 18A-18D , three flexible tabs 1812 are equally distributed around the outer wall of the ring-shaped core so that they are 120 degrees apart from each other. In some variations, four flexible tabs 1812 may be equally distributed so that they are 90 degrees apart from each other, two flexible tabs 1812 may be equally distributed so that they are 180 degrees apart from each other or directly opposite each other, etc. The number of flexible tabs 1812 generally corresponds to the number of lower edges 1724 and associated pairs of guide walls 1726.

[0237] The frictional ring 1530 may further include an outwardly extending surface for engaging and locking with the cuff 1520. For example, the lower surface 1728 of the upper step 1722 of the cuff 1520 may interface with the frictional ring 1530 at the outwardly extending surface. The interface between the lower surface 1728 of the cuff 1520 and the outwardly extending surface of the frictional ring 1530 may serve to maintain the axial position of the cuff 1520 relative to the frictional ring 1530. For example, the frictional ring 1530 may include a protruding circumferential edge 1816. The protruding circumferential edge 1816 may protrude outward at a distal end or region of the outer wall of the ring-shaped core, perpendicular to the height of the outer wall, as best shown in FIG. 18B . The protruding circumferential edge 1816 provides an interface or engagement point for the lower surface 1728 of the cuff 1520. As the cuff 1520 moves axially downward relative to the friction ring 1530, during the transition of the applicator 1500 from the collapsed configuration to the extended configuration, the lower surface 1728 abuts against the protruding circumferential edge 1816, which prevents further downward axial movement of the cuff 1520.

[0238] A damping member 1818 may be positioned on the upper surface of the protruding circumferential edge 1816. The damping member 1818 may be an elastomer or rubber strip or the like that dampens or softens the contact between the lower surface 1728 of the cuff 1520 and the protruding circumferential edge 1816.

[0239] The friction ring 1530 may include more than one protruding circumferential edge 1816, and the protruding circumferential edges 1816 may be distributed circumferentially around the outer wall of the ring-shaped core in an equal or unequal manner. For example, as shown in Figures 18A-18D, three protruding circumferential edges 1816 are equally distributed around the outer wall of the ring-shaped core so that they are 120 degrees apart from each other. In some variations, four protruding circumferential edges 1816 may be equally distributed so that they are 90 degrees apart from each other, two protruding circumferential edges 1816 may be equally distributed so that they are 180 degrees apart from each other or directly opposite each other, etc.

[0240] The friction ring 1530 may include a coupling member that is releasably coupled to a ring retention surface of the housing 1510 and helps lock the shuttle 1540 when the base 1550 is engaged with the housing 1510. For example, in some variations, in a collapsed configuration of the applicator 1500, the friction ring 1530 is collapsed within the cuff 1520, preventing the launch of the shuttle 1540 until the base 1550 is removed.

[0241] For example, the housing 1510 may include at least one ring retention surface, and the friction ring 1530 may include a protrusion 1820 arranged within a cavity defined by the housing body and releasably coupled to the ring retention surface. In response to actuation of at least a portion of the housing 1510 toward the shuttle 1540 (e.g., the applicator may be placed in compression against a user's skin surface, etc.), the ring retention surface of the housing may decouple from the protrusion 1820, which may cause release of a releasable coupling feature coupling the shuttle 1540 and the housing 1510.

[0242] 18C, the protrusions 1820 may be arranged on the inner wall of the ring-shaped core and extend into the friction ring cavity 1810. The protrusions 1820 may include a surface, such as a flat surface, perpendicular or nearly perpendicular to the inner wall of the ring-shaped core that forms a releasable engagement with a ring retention surface of the housing 1510, as described further herein.

[0243] The friction ring 1530 may include more than one protrusion 1820, and the protrusions 1820 may be distributed circumferentially around the inner wall of the ring-shaped core in an equal or unequal manner. For example, as shown in Figures 18A-18D, three protrusions 1820 are equally distributed around the inner wall of the ring-shaped core so that they are 120 degrees apart from each other. In some variations, four protrusions 1820 may be equally distributed so that they are 90 degrees apart from each other, two protrusions 1820 may be equally distributed so that they are 180 degrees apart from each other or directly opposite each other, etc.

[0244] 19A-19E depict a side view of cuff-ring assembly 1900, including cuff 1520 and friction ring 1530, of analyte monitoring device 1500. A top perspective view, a bottom view, a top view, a side view, a side cross-sectional view, and two detail views, respectively, are shown in FIGS. 19A-19E with cuff-ring assembly 1900 in a locked state in which cuff 1520 and friction ring 1530 are locked together.

[0245] The cuff 1520 and the frictional ring 1530 may be locked or secured to one another through one or more engagement and locking features. When the applicator 1500 is in the collapsed configuration, the frictional ring 1530 is collapsed within the cuff 1520, and the engagement and locking features are not interconnected. Upon removal of the base 1550 from the housing 1510, the applicator 1500 transitions from the collapsed configuration to the extended configuration. During this transition, the cuff 1520 is moved or pushed downward while the engagement and locking features become engaged, thereby locking the cuff 1520 and the frictional ring 1530 to one another.

[0246] As best shown in Figures 19A, 19D, and 19E, when the cuff-ring assembly 1900 is in the locked state, the upper portion of the friction ring 1530 extends upward and is exposed out the proximal end of the cuff 1520 such that the upper shoulder 1722 surrounds the upper exposed portion of the friction ring 1530.

[0247] The detail view provided in FIG. 19E is an enlarged view illustrating some of the engagement and locking features of the cuff 1520 and friction ring 1530 in the locked state.

[0248] As shown in close-up D, in the locked position, the lower surface 1728 of the upper step 1722 of the cuff 1520 interfaces with the friction ring 1530 at the protruding circumferential edge 1816. This interface serves to maintain the axial position of the cuff 1520 relative to the friction ring 1530. For example, the protruding circumferential edge 1816 acts as a stop for the cuff 1520. As shown in close-up C, the flexible tab 1812 snaps onto the lower edge 1724 and is held aligned between the pair of guide walls 1726.

[0249] 20A-20F depict a side view of a housing 1510 of an applicator 1500 for an analyte monitoring device 110 according to some variations. A first top perspective view, a second top perspective view, a first bottom perspective view, a second bottom perspective view, a first cross-sectional side view, and a second cross-sectional side view are provided in FIGS. 20A-20F, respectively. The housing 1510 is configured to be manipulated (e.g., manually by a user) to actuate the applicator 1500 and deploy the analyte monitoring device 110, which is releasably retained within the shuttle 1540. The housing 1510 has a housing body 2002 defining a cavity 2010 that receives the cuff 1520, the friction ring 1530, and the shuttle 1540. The housing body 2002 has a distal opening 2004. A first biasing element 1582 (e.g., a first compression spring) may be arranged inside the cavity 2010 on or around a mount 2014 (e.g., a mount or support structure) that extends downwardly from the proximal surface 2012 of the housing body 2002 through the cavity 2010. For example, the mount 2014 may extend from an underside of the proximal surface 2012 of the housing body 2002 such that the mount 2014 extends into the cavity 2010. The mount 2014 may be concentrically aligned or nested with the cuff 1520, the friction ring 1530, and the shuttle 1540. For example, the mount 2014 may extend through the locking friction ring cavity 1810 of the friction ring 1530, and the shuttle shaft 1630 may extend through at least a portion of the mount 2014.

[0250] 20C-20F, the mounting portion 2014 includes a plurality of downwardly extending fingers 2016 arranged in a circumferential configuration. For example, the plurality of downwardly extending fingers 2016 are arranged such that the configuration defines a circular or approximately circular footprint. The circular or approximately circular footprint may correspond to the circumference of the shuttle shaft 1630 such that the shuttle shaft 1630 (e.g., an upper portion of the shuttle shaft 1630) fits within the circular or approximately circular footprint. Variations to the shape and configuration of the footprint defined by the downwardly extending fingers 2016 may be based on the shape and configuration of the shuttle shaft 1630 and / or the first biasing element 1582. Each downwardly extending finger 2016 may be configured to flex or bend outward in response to a force along a portion of the length of the downwardly extending finger 2016.

[0251] One or more retention surfaces and / or features may be formed on the mounting portion 2014. For example, each downwardly extending finger 2016 may have one or more retention members formed thereon. The retention surfaces and / or features may include a ring retention surface including a shoulder 2018 for releasably engaging with a protrusion 1820 of the friction ring 1530 to prevent launch of the shuttle 1540 until removal of the base 1550. For example, the shoulder 2018 may be formed along an outward (e.g., first) surface of the downwardly extending finger 2016 and may engage with the protrusion 1820 by a distal surface of the protrusion 1820 contacting or resting on the shoulder 2018. In some variations, a ring retention slot (e.g., a groove or channel) may be formed through or along the outward surface of the downwardly extending finger 2016, with the ring retention slot terminating at the distal end of the shoulder 2018. The ring retention slot may be sized to allow the protrusion 1820 to progress smoothly but securely along its length. For example, the thickness of the protrusion 1820 may approximate the width of the ring retention slot. In response to actuation of the housing 1510, the housing 1510 is moved downward relative to the cuff 1520 and friction ring 1530. During this downward movement of the housing 1510, the ring retention slot slides downward along the protrusion 1820, and the coupling (e.g., contact) between the shoulder 2018 and the protrusion 1820 is released.

[0252] The retaining surfaces and / or features of each downwardly extending finger 2016 may also include a shuttle retaining surface including a shoulder 2020 for releasably engaging a ledge 1634 of the shuttle 1540 to control axial movement of the shuttle 1540 upon release of the analyte monitoring device 110. For example, the shoulder 2020 may be formed along an inwardly facing (e.g., second) surface of the downwardly extending finger 2016, and the shoulder 2020 may engage a distal surface 1636 of the ledge 1634. The ledge 1634 and the distal surface 1636 may extend circumferentially along the shuttle shaft 1630. Upon actuation of the housing 1510, the engagement between the step 2018 and the protrusion 1820 is released, so that downward movement of the shuttle 1540 toward the distal opening 2004 of the housing body 2002 pushes (e.g., deflects or bends) the shelf 1634 past the shoulder 2020, which is no longer prevented by the friction ring 1530.

[0253] In some variations, each downwardly extending finger 2016 may include a step 2018 formed along an outward-facing surface of the downwardly extending finger 2016 and a shoulder 2020 formed along an opposing inward-facing surface of the downwardly extending finger 2016. The number of downwardly extending fingers 2016 may correspond to the number of protrusions 1820. The downwardly extending fingers 2016 may be circumferentially distributed in an equal or unequal manner. For example, as shown in FIG. 20D , three downwardly extending fingers 2016 are equally distributed within the cavity 2010, 120 degrees apart from each other. In some variations, four downwardly extending fingers 2016 may be equally distributed 90 degrees apart from each other, two downwardly extending fingers 2016 may be equally distributed 180 degrees apart from each other, or directly opposite each other, etc.

[0254] In some variations, the housing 1510 may include one or more guide members along the interior sidewall of the housing body 2002 within the cavity 2010. For example, one or more ribs may extend along the length or portion of the length of the interior sidewall of the housing body 2002 and interface with corresponding outwardly facing members arranged along the length or portion of the length of the cuff 1520. The guide members may help maintain the axial and rotational alignment of the cuff 1520 within the housing body 2002.

[0255] The housing 1510 may further include features for aligning and retaining the locking member 1560 in the movable configuration. For example, a first side opening 2022 formed through a side wall of the housing body 2002 may be sized and shaped to retain the depressible member of the locking member 1560 therein. A pivot surface 2024 may be formed at a height above the first side opening 2022 and may provide a pivot surface for the locking member 1560. For example, the pivot surface 2024 may provide a point along which the locking member 1560 may pivot to release the locking member 1560 from its engagement with the cuff 1520. At a height above the pivot surface 2024, a second side opening 2026 may be formed through the side wall of the housing body 2002. The second side opening 2026 may be sized and shaped to retain the pivot member of the locking member 1560 therein. A flexible contact member 2028 may be formed at a height above the second side opening 2026. The flexible contact member 2028 may be fixed at its proximal end to the side wall of the housing body 2002. The distal end of the flexible contact member 2028 may not be fixed to the side wall of the housing body 2002 and may be configured to flex outward from the side wall in response to an applied force. For example, the distal end of the flexible contact member 2028 may engage a portion of the pivot member of the locking member 1560. When the pivot member pivots outward along the pivot bar 2024, the flexible contact member 2028 flexes outward in response to the pivoting movement but limits the outward pivoting or flexing movement of the locking member 1560.

[0256] In some variations, the housing 1510 may include features for interfacing with and / or securing to the base 1550. For example, one or more recesses or slots may be formed in one or more portions at the distal end of the housing body 2002 to receive a portion of a base sidewall of the base 1550, and / or one or more recesses or slots may be formed in an inner wall of the housing body 2002 to receive a corresponding one or more arms of the base 1550, as further described herein.

[0257] In some variations, the housing 1510 may include or be coupled to an outer enclosure 1570. For example, the outer enclosure 1570 may be a gripping portion, which may include a sheath or ring, that is slid around the housing 1510 or that is coupled to the housing 1510 using a suitable mechanical interfit, such as a thread, an interference fit, or the like. In some variations, the outer enclosure 1570 may be integrally formed (e.g., overmolded) with the housing 1510, and / or the housing 1510 may include one or more gripping features. In some variations, the outer enclosure 1570 may include one or more features to improve a user's ability to manipulate the housing 1510. For example, the outer enclosure 1570 may include one or more concave or otherwise recessed contours with finger-receiving surfaces to improve manual gripping capabilities. Additionally or alternatively, the outer enclosure 1570 may include one or more convex texture features (bumps, ridges, ribs, rings, etc.) to increase friction. Additionally or alternatively, the outer enclosure 1570 may include one or more materials with greater friction (e.g., silicone or other elastomers). In some variations, the outer enclosure 1570 is an elastomeric material that provides an environmental enclosure for the housing body 2002 and the components arranged therein (e.g., by substantially enclosing the housing body 2002). The outer enclosure 1570 may also control acoustics (e.g., reducing sound produced by actuation of the applicator) and vibrations (e.g., damping vibrations between the user and the applicator components produced by actuation of the applicator).

[0258] 21A-21B depict a side view of a locking member 1560 of an applicator 1500 for an analyte monitoring device 110 in front and rear perspective views, respectively. The movable locking member 1560 fits within a corresponding feature of the housing body 2002 and is aligned with and at least partially fits within a retaining wall 1712 formed on the outer wall of the cuff 1520. For example, the periphery of the locking member 1560 at the rear surface may be an elongated member that fits within the retaining wall 1712 defined by a retaining edge 1714. The locking member 1560 includes a depressible member 2110, a pivot bar 2112, and a pivot member 2114 with a flat or substantially flat upper edge 2116. The pressable member 2110 may be in the form of a button or nubby portion and may have a configuration that fits within and extends through the first side opening 2022 of the housing 1510. The pressable member 2110 is generally sized and shaped to allow a user to contact and press the pressable member 2110. The pivot bar 2112 is a bar-like member that extends through the second side opening 2026 of the housing 1510 and along the pivot surface 2024. For example, the pivot bar 2112 movably engages the pivot surface 2024 such that when the pressable member 2110 is pressed inward (e.g., pressed down), the locking member 1560 pivots at the interface between the pivot bar 2112 and the pivot surface 2024. The pivoting movement of the locking member 1560 causes the pivoting member 2114 to move outward. That is, when the pressable member 2110 is pressed or pushed inward within the first opening 2022, the pivot member 2114 moves outward from the second side opening 2026. The outward movement of the pivot member 2114 is controlled or limited by the flexible contact member 2028 of the housing 1510.

[0259] The pivot member 2114 has a flat or substantially flat upper edge 2116 that releasably engages an upper edge on the retaining lip 1714 that defines the retaining wall 1712 of the cuff 1520. In the collapsed configuration of the applicator 1500, the locking member 1560 is positioned within the retaining wall 1712 such that the upper edge 2116 of the movable locking member 1560 engages beneath the upper edge of the retaining lip 1714, preventing downward movement of the cuff 1520 relative to the housing body 2002. In response to depression of the locking member 1560, vertical movement of the cuff 1520 is no longer impeded due to outward movement of the pivot member 2114 away from the upper edge of the retaining lip 1714.

[0260] The locking member 1560 is thus engaged with the cuff 1520 in a first configuration and disengaged from the cuff 1520 in a second configuration. In some variations, movement of the locking member 1560 from the first configuration to the second configuration releases the cuff 1520, thereby uncoupling the proximal surface of the base 1550 from the housing body 2002, as described further herein.

[0261] In some variations, one locking member 1560 is provided. In some variations, two locking members 1560 are provided. The incorporation of two locking members 1560 provides a locking system for the applicator 1500 that requires careful and controlled user action (e.g., simultaneous or near-simultaneous depression of two locking members 1560) to unlock the applicator 1500 and transition the applicator 1500 from the collapsed configuration to the extended configuration for deployment of the analyte monitoring device 110.

[0262] 22A-22G depict a side view of a base 1550 of an applicator 1500 for an analyte monitoring device 110 according to some variations. The base 1550 is shown in a top perspective view, a top view, a bottom view, a first side view, a first cross-sectional side view, a second side view, and a second cross-sectional side view in FIGS. 22A-22G, respectively. Generally, the base 1550 provides an enclosed area for the analyte monitoring device 110 before a user is ready to apply the analyte monitoring device 110. The base 1550 is removably coupled to the housing body 2002 at a distal opening 2004. The base 1550 is held in place through releasable engagement between features of the base 1550, the cuff 1520, and the housing body 2002, as further described herein. The base 1550 is removed from its releasable engagement with the cuff 1520 and housing body 2002 in response to movement of the locking member 1560 from the first configuration to the second configuration, after which a removal force is applied by the user to the base 1550. The release of the locking member 1560 from engagement with the upper edge of the retaining edge 1714 of the cuff 1520 allows the cuff 1520 to translate vertically toward the distal opening 2004 of the housing body 2002. Movement of the cuff 1520 toward the distal opening 2004 contacts and pushes the base 1550 in the same direction.

[0263] As the cuff 1520 advances downward, the shuttle 1540 engages one or more downwardly extending fingers 2016 therein. Shoulder 1520 is moved axially downward to a position where the friction ring 1530 engages a ledge 1634 formed on the shuttle shaft 1630 (e.g., at the distal surface 1636). The cuff 1520 is further advanced downward until it is stopped by the protruding circumferential edge 1816 of the friction ring 1530, which is locked into the cuff 1520 via engagement on the lower edge 1724 of the flexible tab 1812. While the cuff 1520 is being moved axially downward, further movement of the shuttle 1540 causes one or more downwardly extending fingers 2016 to engage with the protruding circumferential edge 1816 of the friction ring 1530. Shoulder2020. Meanwhile, further downward movement results in the base 1550 being pushed further downward such that the restraining arms of the base 1550 prevent the base 1550 from being reattached and the retaining arms of the base 1550 are in a position where a user-applied removal force to the base 1550 causes the base 1550 to be released. In response to a user-applied removal force to the base 1550, the applicator 1500 is brought to an extended configuration in which the components of the applicator 1500 are aligned and ready to apply the analyte monitoring device 110 in response to actuation of the housing 1510.

[0264] 22A-22G, the base 1550 has a proximal surface 2210 with a base sidewall 2212 extending upwardly from a portion of the proximal surface 2210. The proximal surface 2210 may have a generally flat surface with a curved edge that abuts against the bottom edge of the housing body 2002 and / or outer enclosure 1570 to form a sealed enclosure therebetween. In some variations, the base sidewall 2212 may extend continuously in a circular or generally circular arrangement. In some variations, the base sidewall 2212 may be separate and discrete members that together form a circular or generally circular footprint. The upper edge of the base sidewall 2212 may fit into a corresponding recess formed in the bottom edge of the housing body 2002 so that the base sidewall 2212 is surrounded by the housing body 2002 when the applicator 1500 is in the collapsed configuration.

[0265] The base 1550 may be configured to form a secure attachment when the microneedle enclosure 500 is connected to the analyte monitoring device 110. For example, the interior portion of the base 1550 may be sized and shaped so that the clamp 520 (of the microneedle enclosure 500) can mate with and / or be contained within the interior portion. In some variations, the base 1550 includes a receiving area or compartment that provides a surrounding enclosure for the microneedle enclosure 500. The microneedle enclosure 500 and the base plate 330 of the analyte monitoring device 110 may be contained within the receiving area of ​​the base 1550 when attached to one another via the locking tabs 528 and connecting members 332. Engagement may occur between the outer engagement feature 526 of the microneedle enclosure 500 and a clamp engagement feature formed within the receiving area of ​​the base 1550, as further described herein.

[0266] 22H-22J depict a side view of base 1550 and microneedle enclosure 500 in an exploded view, a top perspective view, and a side cross-sectional view, respectively, as further described herein.

[0267] In some variations, the receiving area may include an enclosure sidewall 2214 extending upward from a central region of the proximal surface 2210 inwardly relative to the base sidewall 2212. The enclosure sidewall 2214 may form a perimeter that surrounds or interfaces with the outer periphery of the base plate 330 of the analyte monitoring device 110. Within the enclosure sidewall 2214, the clamp engagement feature may include a plurality of upwardly extending flexible fingers 2216, each having a chamfer or beveled edge, and a plurality of walls 2217, each engaging with the outer engagement feature 526 of the clamp 520. The upwardly extending flexible fingers 2216 flex outward to receive the microneedle enclosure 500, the chamfer or beveled edge securing to the microneedle enclosure 500, and the walls 2217 limiting the rotational movement of the microneedle enclosure 500. The flexible fingers 2216 may be positioned in an alternating configuration with the walls 2217, and the flexible fingers 2216 and walls 2217 may be positioned circumferentially around the inner circumference of the enclosure side wall 2214 such that the flexible fingers 2216 and walls 2217 form an occupation area for the clamp 520.

[0268] 5E and 5F , the outer engagement features 526 of the clamp 520 may include an extending surface that projects orthogonally from a central region of the clamp 520 and terminates in a fin that extends orthogonally from the extending surface to at or near the proximal end of the clamp 520. The outer engagement features 526 of the clamp 520 may be positioned circumferentially around the outer edge of the clamp 520, and each outer engagement feature 526 (including the extending surface and fin) may correspond to a respective flexible finger 2216 and wall 2217 of the base 1550. The extended surfaces of the clamps 520 may interface with the flexible fingers 2216 such that, in response to the application of pressure therebetween, the extended surfaces are secured beneath the upper edges of the flexible fingers 2216 (e.g., the flexible fingers 2216 flex outward in response to pressure, allowing the extended surfaces to snap-fit ​​beneath the chamfered or beveled upper edges of the flexible fingers 2216).

[0269] Rotational movement of clamp 520 is limited or restricted due to the interface between the fins of clamp 520 and wall 2217. For example, rotational movement of clamp 520 is stopped in response to contact between the fins of clamp 520 and wall 2217 of base 1550. Because clamp 520 has a rotatable connection with connecting member 332 of base plate 330 (as described above with reference to FIGS. 5E, 5F, and 5G), rotation of clamp 520 while held within the clamp engagement feature of base 1550 can result in disengagement of clamp 520 and base plate 330. For example, by rotating the clamp 520 so that the clamp's locking tab 528 disengages from the connector feature 336 of the base plate 330, the microneedle enclosure 500 (held within the base 1550 by the clamp engagement features (e.g., engagement of the flexible fingers 2216 and the extended surface of the clamp 520)) can be lifted from the base plate 330.

[0270] Thus, once the analyte monitoring device 110, along with the microneedle enclosure 500, is fitted into the base 1550, the microneedle array 140 of the analyte monitoring device 110 is contained within the sterile environment provided by the capsule 510 until removal of the compressive engagement between the clamp 520 and the base plate 330. In some variations, once the microneedle enclosure 500 is attached to the base 1550, and the base 1550 is attached to the housing 1510, the rotational locking arrangement between the microneedle enclosure 500 and the base plate 330 can be disengaged, for example, through a manufacturing operation, which retains the engagement between the flexible fingers 2216 and the microneedle enclosure 500. The microneedle array 140 then remains in that sterile environment due to compression from the biasing elements 530, 1582, and 1584 until the base 1550 is disengaged from the housing 1510. Disengagement of the base 1550 results in removal of the microneedle enclosure 500 and base 1550 as the microneedle enclosure 500 is rotatably disengaged from the base plate 330 (through a pre-manufacturing disengagement operation) and secured within the base 1550 through a snap-fit ​​attachment with the flexible fingers 2216.

[0271] In some variations, the base 1550 includes arms that aid in engagement and disengagement between the base 1550, the cuff 1520, and the housing body 2002. The base 1550 may include restraining arms 2218 extending from the proximal surface 2210 in an upwardly protruding configuration. The restraining arms 2218 may be configured to flex or snap into restraint retention recesses formed in the sidewalls of the housing body 2002 when the base 1550 is connected to the housing body 2002. For example, during assembly of the applicator 1500, the restraining arms 2218 may be flexed inward, allowing the outwardly protruding surfaces of the restraint arms 2218 to be positioned (e.g., snapped into) and biased radially outwardly within the restraint retention recesses. During release of the base 1550 as the base 1550 is pushed downward, the restraining arm 2218 is disengaged from (e.g., pulled out of) the restraining retention recess and is pushed past a walled surface formed in the side wall of the housing body 2002 in the downward axial movement of the base 1550. Once the restraining arm 2218 is moved past the walled surface, the user is prevented from reattaching the base 1550 to the housing body 2002 due to the walled surface blocking the upward axial movement of the restraining arm 2218.

[0272] In some variations, the base 1550 may include more than one restraint arm 2218, and the restraint arms 2218 may be distributed circumferentially around and / or positioned within the proximal surface 2210 in an equal or unequal manner. For example, as shown in FIG. 22A , the base 1550 includes four restraint arms 2218 distributed around the proximal surface 2210.

[0273] In some variations, the restraining arms 2218 may be flexed outward, allowing the outwardly protruding surfaces of the restraining arms 2218 to be positioned within (e.g., snapped into) the restraining retention recesses and biased radially inward.

[0274] The base 1550 includes retaining arms that releasably engage base retaining surfaces of the cuff 1520. The configuration of the retaining arms with the base retaining surfaces of the cuff 1520 and with the housing body 2002 prevents the base 1550 from disengaging from its engagement with the cuff 1520 and the housing body 2002 when the applicator 1500 is in the collapsed configuration. For example, the base 1550 may include retaining arms 2220 extending from the proximal surface 2210 in an upwardly protruding configuration. When the applicator 1500 is in the collapsed configuration, the retaining arms 2220 may be sandwiched between the outer surface of the cuff 1520 and the inner surface of the housing body 2002. The inwardly protruding surfaces of the retaining arms 2220 may engage the base retaining surfaces 1730 of the cuff 1520. This engagement or locking configuration prevents separation between the base 1550 and the housing body 2002. During release of the base 1550, the base 1550 is pushed downward along with the cuff 1520, and the engagement between the retaining arms 2220 and the base retaining surfaces 1730 is maintained. Once the engagement point passes the housing body 2002, the base 1550 is in a configuration in which the base 1550 can be removed by a user-applied removal force.

[0275] In some variations, the base 1550 may include more than one retaining arm 2220, and the releasable retaining arms 2220 may be distributed circumferentially around the proximal surface 2210 in an equal or unequal manner. For example, as shown in FIG. 22A, the base 1550 includes four releasable retaining arms 2220 distributed around the proximal surface 2210.

[0276] In some variations, the length of the restraining arm 2218 exceeds the length of the retaining arm 2220. In some variations, the length of the retaining arm 2220 exceeds the length of the restraining arm 2218. In some variations, the length of the restraining arm 2218 is equal to or approximately equal to the length of the retaining arm 2220.

[0277] 22K depicts a side view, in a top perspective view, of the applicator base 1550 engaged with the cuff 1520. As shown, the cuff 1520 includes a bottom flange 1732 with an increased surface area and a cutout 1734 formed therethrough to accommodate the arms of the base 1550 (e.g., the arresting arm 2218 and the retaining arm 220).

[0278] 23A-23O depict, in cross section and close-up, views of applicator 1500 in an assembled form according to variations described herein. FIGS. 23A-23F illustrate applicator 1500 in a collapsed configuration. FIGS. 23G-23K illustrate applicator 1500 during the process of releasing base 1550 from engagement with housing body 2002, transitioning applicator 1500 from the collapsed configuration to the extended configuration. FIGS. 23L-23O sequentially illustrate applicator 1500 moving from the extended configuration, in which analyte monitoring device 110 is ready for release, to the released configuration, in which analyte monitoring device 110 is released from applicator 1500. Analyte monitoring device 110 is shown in several views in FIGS. 23A-23O. If details of the analyte monitoring device 110 are not necessary for the particular aspect being illustrated, the analyte monitoring device 110 may be omitted from the figure. The microneedle enclosure 500 is shown in some of the figures in Figures 23A-23O, but is omitted from other figures if details of the microneedle enclosure 500 are not necessary for the particular aspect being illustrated.

[0279] 23A-23F, applicator 1500 is depicted in a collapsed configuration in which the components are locked (e.g., fixed) relative to one another and analyte monitoring device 110 cannot be deployed.

[0280] In the collapsed configuration, the friction ring 1530 is collapsed into the cuff 1520 and the locking member 1560 is engaged with the cuff 1520. The second biasing element 1584 is positioned within the inner cavity 1632 defined by the shuttle shaft 1630 and is compressed to a first compression of the second biasing element 1584. The first biasing element 1582 is positioned within the cavity 2010 defined by the housing body 2002 and is compressed to a first compression of the first biasing element 1582. The ledge 1634 (e.g., distal surface 1636) of the shuttle shaft 1630 is positioned proximal to (e.g., with a gap therebetween) the shoulder 2020 of the downwardly extending finger 2016. The analyte monitoring device 110 is retained by the shuttle 1540.

[0281] In the collapsed configuration of the applicator 1500, the locking tab 528 of the microneedle enclosure and the connector feature 336 of the base plate 330 are disengaged. The sterile seal provided by the microneedle enclosure 500 is maintained by the opposing forces of the microneedle enclosure biasing element 530 and the first and second biasing elements 1582, 1584. Additionally, because the analyte monitoring device 110 is maintained between these opposing forces, the analyte monitoring device 110 is able to move relative to the components of the applicator 1500. This movement allows the bumper 512 (e.g., a seal around the capsule 510) to be securely held in contact with the analyte monitoring device, thereby maintaining sterility through vibration, temperature changes, and other environmental conditions.

[0282] 23A , the microneedle enclosure 500 is contained within a base 1550 and connected to the analyte monitoring device 110. The outer engagement features 526 of the microneedle enclosure 500 are secured beneath the chamfered or beveled upper edges of the flexible fingers 2216 formed in the base 1550, allowing the microneedle enclosure 500 to be removed upon release of the base 1550 from the housing body 2002. As shown in FIG. 23A , in the collapsed configuration, the distal edges of the shuttle 1540 and cuff 1520 are in a proximal-most position and positioned proximal to the distal opening 2004 of the housing body 2002. In some variations of the collapsed configuration, the distal edges of the shuttle 1540 and cuff 1520 are positioned proximal to the distal opening 2004 of the housing body 2002.

[0283] 23B, a detailed view of locking member 1560 is provided, which fits within retaining wall 1712 formed on the outer wall of cuff 1520. The enlarged view depicts the upper edge 2116 of locking member 1560, which is engaged just below the upper edge of retaining edge 1714 of retaining wall 1712. This engagement between locking member 1560 and cuff 1520 prevents downward movement of cuff 1520 relative to housing body 2002. Because frictional ring 1530 is collapsed into cuff 1520 when applicator 1500 is in the collapsed configuration, the engagement and locking features of cuff 1520 and frictional ring 1530 are not interconnected.

[0284] The arrangement of the frictional ring 1530 within the cuff 1520, as shown in FIGS. 23C and 23D , prevents firing of the shuttle 1540 in the collapsed configuration. This is because the frictional ring 1530 prevents vertical displacement of the shuttle 1540 toward the distal opening 2004 when the frictional ring 1530 is collapsed within the cuff 1520 and sandwiched between the cuff 1520 and the mounting portion 2014 of the housing 1510; i.e., the position of the frictional ring 1530 prevents the downwardly extending fingers 2016 of the mounting portion from flexing a sufficient amount to allow vertical displacement of the shuttle 1540. In other words, when the applicator 1500 is in the collapsed configuration, the shuttle 1540 is locked in place due to the concentric arrangement of the mounting portion 2014, frictional ring 1530, and cuff 1520.

[0285] 23E and 23F depict a side view of the base 1550 engaged with the housing body 2002 and cuff 1520 when the applicator 1500 is in the collapsed configuration. The upper edge of the base sidewall 2212 fits into a corresponding recess formed in the distal edge of the housing body 2002 such that the base sidewall 2212 is surrounded by the housing body 2002. The restraining arms 2218 of the base 1550 fit into restraining retention recesses formed in the sidewalls of the housing body 2002, as shown in the enlarged view of FIG. 23E. The retaining arms 2220 of the base 1550 are sandwiched between the outer surface of the cuff 1520 and the inner surface of the housing body 2002, as shown in the enlarged view of FIG. 23F. For example, the inwardly projecting surfaces of the retaining arms 2220 engage the base retaining surfaces 1730 of the cuff 1520 to prevent separation between the base 1550 and the housing body 2002 .

[0286] 23G-23K, aspects associated with the release of the base 1550 from engagement with the housing body 2002, transitioning the applicator 1500 from the collapsed configuration to the extended configuration, are illustrated. In response to depression of the locking members 1560 (e.g., when the pushable members 2110 are pressed inward to move from the first configuration to the second configuration), each locking member 1560 pivots at the interface between the pivot bar 2112 of the locking member 1560 and the pivot surface 2024 of the housing body 2002. The pivoting movement moves the pivot members 2114 of the locking members 1560 outward within the second side openings 2026, and the upper edges 2116 of the pivot members 2114 are no longer locked below the upper edge of the retention edge 1714 of the cuff 1520. Thus, in response to depression of the locking member 1560, vertical movement of the cuff 1520 is no longer impeded due to outward movement of the pivot member 2114 away from the upper edge of the retaining lip 1714. In the extended configuration of the applicator 1500, the distal edge of the cuff 1520 is in a distal-most position and the shuttle 1540 is in an intermediate position. In some variations of the extended configuration, the distal edge of the cuff 1520 is positioned distal to the distal opening 2004 of the housing body 2002 and the shuttle 1540 is positioned proximal to the distal opening 2004 of the housing body 2002. In some variations of the extended configuration, the distal edge of the cuff 1520 is positioned distal to the distal opening 2004 of the housing body 2002 and the shuttle 1540 is positioned proximal to the distal opening 2004 of the housing body 2002.

[0287] FIG. 23G illustrates disengagement between the cuff 1520 and the locking member 1560. Release of the locking member 1560 from engagement with the upper edge of the retaining edge 1714 of the cuff 1520 allows the cuff 1520 to translate vertically downward, as shown in FIG. 23G. The downward movement of the cuff 1520 pushes the base 1550 (e.g., at the proximal surface 2210) in the same downward direction. The enlarged view in FIG. 23G depicts release of the locking member 1560 from engagement with the upper edge of the retaining edge 1714 of the cuff 1520, with the outward movement of the pivot member 2114 limited by the flexible contact member 2028 of the housing body 2002.

[0288] Figure 23H depicts details of the engagement between the cuff 1520 and the friction ring 1530. During the downward movement of the cuff 1520, the cuff 1520 moves axially such that the friction ring 1530 extends out from the upper surface of the cuff 1520 and locks within it. More specifically, the cuff 1520 moves axially downward relative to the friction ring 1530 along the length of the flexible tab 1812. The flexible tab 1812 is flexed or pushed inward until the cuff 1520 passes the distal end of the flexible tab 1812, at which point the flexible tab 1812 snaps onto the lower edge 1724 (and is held between a pair of guide walls 1726, not shown in Figure 23H). Further downward progression of the cuff 1520 is stopped by the protruding circumferential edge 1816 of the friction ring 1530, which provides an interface or engagement point for the underside 1728 of the cuff 1520. The engagement between the cuff 1520 and the friction ring 1530 prevents the cuff 1520 from moving distally relative to the distal opening 2004 of the housing body 2002.

[0289] Figure 23I depicts a detail of the microneedle enclosure 500 being removed along with the base 1550. The microneedle enclosure 500 is removed along with the base 1550 due to the fixed engagement of the outer engagement feature 526 of the clamp 520 with the upper edges of the flexible fingers 2216 formed in the base 1550. The close-up of Figure 23I depicts the interface between the extended surfaces (of the outer engagement feature 526) and the flexible fingers 2216. As shown and described herein, the flexible fingers 2216 flex outward in response to pressure, allowing the extended surfaces to snap-fit ​​and be retained beneath the chamfered or beveled upper edges of the flexible fingers 2216. Axial displacement of the cuff 1520 pushes the base 1550, and the microneedle enclosure 500, which is secured beneath the flexible fingers 2216, moves with the base 1550. This movement of the microneedle enclosure 500 breaks the sterile seal between the capsule 510 and the microneedle array 140. Thus, in the extended configuration, the microneedle enclosure 500 does not surround the microneedle array 140.

[0290] 23J and 23K depict a side view of the arms of the base 1550 as the base 1550 is pushed downward during transition of the applicator 1500 to the extended configuration. FIG. 23J illustrates that the restraining arms 2218 disengage from the restraining retention recesses of the housing body 2002. As shown in the enlarged view of FIG. 23J, once the restraining arms 2218 are pushed beyond the restraining retention recesses, the user is prevented from reattaching the base 1550 to the housing body 2002 due to the walled surface directly below the restraining retention recess blocking upward axial movement of the restraining arms 2218. FIG. 23K illustrates that engagement between the retaining arms 2220 and the base retaining surface 1730 is maintained as the base 1550, along with the cuff 1520, is pushed downward. Once the engagement point passes beyond the housing body 2002, the base 1550 is configured in such a way that the base 1550 can be removed by a user-applied removal force. For example, a user can grasp the base 1550 and pull the base 1550 apart, the pulling force overcoming the engagement between the retaining arms 2220 and the base retaining surfaces 1730.

[0291] 23L-23O, relevant aspects of applicator 1500 are shown moving from an extended configuration to a released configuration. In the extended configuration, the components of applicator 1500 are arranged and configured such that analyte monitoring device 110 can be deployed (e.g., released) from applicator 1500 in response to actuation of housing 1510. Base 1550 is removed and shuttle 1540 is moved to a fired position in the extended configuration. In the released configuration, analyte monitoring device 110 is released from applicator 1500 and inserted into a user's skin.

[0292] During actuation of the housing 1510, the friction ring 1530 and cuff 1520 act as a single component and function to cause disengagement of the analyte monitoring device 110 from the shuttle 1540. The shuttle 1540 is axially aligned and nested within the friction ring 1530. FIG. 23L depicts a detail of the shuttle 1540 positioned in the extended configuration. In the extended configuration, the mount 2014 is releasably engaged with the friction ring 1530, and the mount 2014 is releasably engaged with the shuttle 1540. In this configuration, the shuttle 1540 is moved to a position in which the shoulders 2020 of the downwardly extending fingers 2016 therein are engaged with the shelves 1634 of the shuttle shaft 1630, and the steps 2018 of the downwardly extending fingers 2016 are engaged with the protrusions 1820 of the friction ring 1530, as shown in the enlarged view of FIG. 23L.

[0293] 23M, 23N, and 23O detail first, second, and third cross-sectional views, respectively, of applicator 1500 in the released configuration. In particular, FIGS. 23M, 23N, and 23O depict the arrangement of applicator components when applicator 1500 is in the released configuration in which analyte monitoring device 110 is deployed from shuttle 1540. As shown in FIGS. 23M, 23N, and 23O, second biasing element 1584 is not significantly compressed because, when loaded, energy stored within second biasing element 1584 is transferred to shuttle 1540 to drive analyte monitoring device 110 with a suitable applied force. In the released configuration, analyte monitoring device 110 is released from shuttle 1540. In the released configuration, the distal edge of cuff 1520 is in an intermediate position, and shuttle 1540 is in a distal-most position. In some variations of the release configuration, the distal edge of the cuff 1520 and the shuttle 1540 are each positioned distal to the distal opening 2004 of the housing body 2002. In some variations of the release configuration, the distal edge of the cuff 1520 is positioned distal to the distal opening 2004 of the housing body 2002, and the shuttle 1540 is positioned distal to the distal opening 2004 of the housing body 2002.

[0294] FIG. 23M depicts details of the disengagement between the friction ring 1530 and the housing body 2002. More specifically, as shown in the enlarged view of FIG. 23M, as the housing body 2002 is actuated (e.g., pushed downward), the protrusion 1820 of the friction ring 1530 disengages from the shoulder 2018 of the housing 1510. The downward movement causes disengagement between the friction ring 1530 and the downwardly extending finger 2016 on which the shoulder 2018 is formed, thereby releasing the releasable coupling feature between the shuttle 1540 and the downwardly extending finger 2016. More specifically, the downward movement of the shuttle 1540 pushes the ledge 1634 over the shoulder 2020 (e.g., causing the downwardly extending finger 2016 to bend away from the shuttle 1540). This bending or flexing is possible because the downwardly extending fingers 2016 are no longer blocked or obstructed by the protrusions 1820. Additionally, during actuation of the housing body 2002, as the housing body 2002 is moved downwardly relative to the cuff 1520 and friction ring 1530, the ring retention slots formed in the outwardly facing sidewalls of the downwardly extending fingers 2016 slide distally along the protrusions 1820.

[0295] 23N and 23O depict details of tracks 1716 formed along the cuff 1520 through which one or more tracking protrusions 1616 on the shuttle 1540 travel during actuation of the housing body 2002. Each track 1716 terminates at a distal end with a shuttle flex surface 1718 that acts as a stop for axial movement of the shuttle 1540 to assist in radially outward flexing of the flexible leaves 1612 of the shuttle 1540, as shown in the enlarged view of FIG. 23O. Using the radially outward flexing of the flexible leaves 1612, the analyte monitoring device 110 is released from the shuttle 1540. The second biasing element 1584 provides the external pressure for radially outward flexing as the second biasing element 1584 is compressed within the inner cavity 1632 of the shuttle 1540. The shuttle flexing surface 1718 of the cuff 1520 stops the axial movement of the shuttle 1540, and the energy stored in the second biasing element 1584 is transferred to the shuttle 1540, thereby flexing the flexible leaves 1612 radially outward and ejecting the analyte monitoring device 110 with a suitable applied force (e.g., for suitable insertion of the microneedle array 140 into the user's skin). The adhesive layer (e.g., outer adhesive layer 344) adheres the analyte monitoring device 110 to the user's skin while the microneedle array 140 is inserted into the user's skin. The analyte monitoring device 110 may be removed with sufficient force applied to overcome the adhesive layer.

[0296] FIG. 24 is a process flow chart including a process for moving the applicator 1500 from the collapsed configuration to the extended configuration and moving the analyte monitoring device 110 into a position for release. P2400 The process is illustrated in the following diagram along the left side of the process flow chart: S2410 from, S2420, S2430, S2440 , and S2450 24. The sides connected by dashed lines and within dashed boxes depict different states and configurations of the applicator components following each of the process steps. The order in which the different states and configurations occur may vary and is not limited to that shown in FIG.

[0297] S2410 , locking member 1560 is depressed (e.g., moved from a first configuration to a second configuration). Depressing locking member 1560 includes locking member 1560 becoming disengaged from cuff 1520.

[0298] S2420 , the cuff 1520 undergoes axial displacement toward the distal end 2004 of the housing body 2002. This axial displacement of the cuff 1520 causes engagement between the cuff 1520 and the frictional ring 1530. In particular, the flexible tab of the frictional ring 1530 snaps onto the lower edge of the cuff 1520, and the protruding edge of the frictional ring 1530 engages the underside of the proximal end of the cuff 1520. Additionally, the first biasing element 1582 moves from its first state of compression of the first biasing element to a second state of compression that is less than the first state of compression.

[0299] S2430 20, the base 1550 undergoes axial displacement as the cuff 1520 is pressed against the base proximal surface 2210. The axial displacement of the base 1550 breaks the sterile seal provided by the microneedle enclosure 500. The axial displacement of the base 1550 also disengages the restraining arms of the base 1550 from the restraining recesses in the housing body 2002.

[0300] S2440 15, the shuttle 1540 descends to a firing position. In the firing position, the shuttle 1540 is configured to launch or advance the analyte monitoring device 110 for insertion of the analyte monitoring device 110 into the skin of a user. As the shuttle 1540 descends to the firing position, the downwardly extending finger shoulder 2020 engages the shuttle shaft ledge 1634. The second biasing element 1584 moves from its first compressed state of the second biasing element to a second compressed state that is slightly less than the first compressed state due to the axial displacement of the shuttle 1540 to the fired position.

[0301] S2450, the base 1550 is pulled apart. The base 1550 can be pulled apart by the user applying an appropriate force. At this point, the applicator 1500 is in the extended configuration.

[0302] FIG. 25 is a process flow chart including the process of moving the applicator 1500 from the extended configuration to the released configuration and inserting an analyte monitoring device. P2500 The process is illustrated in the following diagram along the left side of the process flow chart: S2510 from, S2520, S2530, and S2540 25. The sides connected by dashed lines and within the dashed boxes depict different states and configurations of the applicator components following each of the process steps. The order in which the different states and configurations occur may vary and is not limited to that shown in FIG.

[0303] S2510 , the applicator 1500 is placed on the user in the extended configuration, with the distal end of the cuff 1520 contacting the human skin at the insertion site where the applicator 1500 is placed.

[0304] S2520 , the housing body 2002 is actuated (e.g., pushed downward for axial displacement). The actuation causes a gap or decoupling between the protrusion 1820 of the friction ring 1530 and the shoulder 2018 formed on the downwardly extending finger 2016. The decoupling is caused by the axial displacement of the downwardly extending finger 2016 due to its connection within the cavity 2010 of the housing body 2002. The shelf 1634 of the shuttle shaft is pushed over the shoulder 2020 of the downwardly extending finger. The actuation further moves the first biasing element 1582 beyond its second compressed state to a third compressed state of the first biasing element. In addition to the movement and / or change of applicator components in response to the actuation, the actuation also causes a bulging of the human skin within an area defined by the distal edge of the cuff 1520.

[0305] S2530 In step (a), the shuttle 1540 is displaced axially toward the distal opening 2004 of the housing body 2002. The second biasing element 1584 moves to a third compressed state of the second biasing element, which is less than its second compressed state. The axial displacement of the shuttle 1540 causes the microneedle array 140 to contact the human skin and insert at the insertion site. The continued axial displacement of the shuttle 1540 causes the adhesive to adhere to the human skin at the insertion site.

[0306] S2540 At this point, the tracking projections on the shuttle 1540 engage the shuttle flexing surfaces of the cuff 1520. The engagement between the tracking projections and the shuttle flexing surfaces causes the flexible leaves of the shuttle 1540 to flatten or flex radially outward, thereby releasing the analyte monitoring device.

[0307] 26A and 26B depict a side view of the shuttle arresting mechanism in cross section and in an enlarged view. As shown, a ledge 1634 formed on the shuttle shaft 1630 includes a distal surface 1636 and a proximal surface 1638. The proximal surface 1638 of the ledge 1634 may, in some variations, be used as a shuttle arresting feature. FIG. 26A illustrates the applicator 1500 in an extended configuration in which the distal surface 1636 of the ledge 1634 of the shuttle shaft 1630 is engaged with the shoulder 2020 of the downwardly extending finger 2016 to control movement of the shuttle 1540 toward the distal opening 2004 of the housing body 2002.

[0308] 26B illustrates how the proximal surface 1638 of the ledge 1634 prevents axial movement of the shuttle 1540 toward the proximal end of the housing body 2002. Axial movement toward the proximal end is prevented after disengagement of the distal surface 1636 of the ledge 1634 and the shuttle retaining surface (e.g., shoulder 2020). The proximal surface 1638 abuts against the distal end of the shoulder 2020, preventing axial movement of the shuttle 1540 toward the proximal end of the housing body 2002. The distal end of the shuttle retaining surface may be a flat or nearly flat surface to prevent the proximal surface 1638 from being pushed past the shuttle retaining surface.

[0309] As described above, the analyte monitoring device may include a housing. The housing may at least partially surround or enclose other components (e.g., electronic components) of the analyte monitoring device, such as to protect such components. For example, the housing may be configured to help prevent dust and moisture from entering the analyte monitoring device. In some variations, an adhesive layer may attach the housing to a surface (e.g., skin) of a user while allowing the microneedle array to extend outward from the housing and into the user's skin. Furthermore, in some variations, the housing may generally include rounded edges or corners and / or have a low profile so as to be atraumatic and reduce interference with clothing worn by the user, etc.

[0310] For example, as shown in FIGS. 27A-27E, an exemplary variation of an analyte monitoring device 300 includes a housing 310 configured to at least partially enclose various other internal components of the device 300 and a microneedle array extending outward from the skin-facing surface (e.g., underside) of the housing 310. 331 and

[0311] The housing 310 may include one or more rigid or semi-rigid protective shell components that may be coupled together via, for example, suitable fasteners (e.g., mechanical fasteners), mechanical interlocking or interlocking features, and / or an engineering fit. For example, as shown in FIG. 27E, the housing may include a housing cover 310a and a housing base 310b, where the cover 310a and base 310b may be secured together with one or more threaded fasteners (e.g., fasteners that engage threaded holes in the upper and / or lower housing portions). The cover 310a and base 310b may include radiused edges and corners and / or other atraumatic features. When coupled together, the cover 310a and base 310b securely fasten to the device printed circuit board. 351 (PCB), sensor assembly 321310, and / or other components such as gasket 312. For example, the internal components arranged within the internal volume may be arranged in a compact, low-profile stack as shown in FIG. 27E. While FIG. 27E illustrates that housing 310 includes multiple housing components, in some variations, housing 310 may include a single component that defines an internal volume for storing the internal device components. In some embodiments, housing 310 may be filled with a suitable potting compound (e.g., epoxy) to reduce deleterious environmental effects such as temperature, humidity, pressure, and light.

[0312] Additionally, analyte monitoring device 300 may include an adhesive layer 340 configured to attach housing 310 to a surface (e.g., skin) of a user. Adhesive layer 340 may be, for example, a double-sided adhesive liner as shown in the variation depicted in FIG. 27D. 345 Alternatively, adhesive layer 340 may be bonded directly to the skin-facing side of housing 310 using one or more suitable fasteners (e.g., adhesive, mechanical fasteners, etc.). Adhesive layer 340 may be protected by a release liner that a user removes prior to skin application to expose the adhesive. In some variations, the analyte monitoring device may be mounted on a 3M® PET film, available from 3M®. 1504XL TM Double-sided adhesive and 3M® 4076 TM Skin-facing adhesives may also be included. These materials are selected for their breathability, wearability, mean moisture vapor transmission rate (MWVTR), biocompatibility, compatibility with sensor sterilization methods / strategies, appearance, durability, adhesion, and ability to retain said adhesion for the duration of sensor wear.

[0313] The adhesive layer 340, in some variations, may have a perimeter that extends further than the perimeter or periphery of the housing 310 (e.g., this may increase the surface area for attachment, increasing the stability of retention or attachment to the user's skin). Additionally, in some variations, the adhesive layer 340 may extend outwardly from the microneedle array. 331 The opening 342 may include an opening to allow passage of the microneedle array, as shown in FIG. 27C. 331 The microneedle array may have a size and shape that closely circumscribes the shape of the microneedle array (e.g., a square opening that closely corresponds in size and shape to the square microneedle array), or another suitable size and shape that is larger than the footprint of the microneedle array (e.g., a circular opening that is larger than the square microneedle array).

[0314] While the housing 310 depicted in Figures 27A-27E is hexagonal in shape and generally prismatic, it should be understood that in other variations, the housing 310 can have any suitable shape. For example, in other variations, the housing may be generally prismatic and have a base that is oval (e.g., circular), triangular, rectangular, pentagonal, or other suitable shape. As another example, Figures 28A-28C show a dome-shaped housing. 411 28A-28C illustrate an example variation of an analyte monitoring device 400 including a dome-shaped housing. 411 is generally circular, however, in other variations the dome-shaped housing may have a base having another suitable oval or polygonal shape.

[0315] Similar to the housing 310, 411 may include an interior volume configured to at least partially surround other components of analyte monitoring device 400. For example, as shown in the cross-sectional view of FIG. 411 Among them, the device PCB 451 and microneedle arrays 431 to form an interior volume in which a sensor assembly with 411b A dome-shaped cover is attached to the 411a In addition, the housing 411may be configured to bond to a surface via an adhesive layer 440, and the microneedle array 431 may extend outward from the housing and beyond adhesive layer 440. Additionally, as shown in Figures 28D and 28E, adhesive layer 440 may extend outward from the housing 411 It may extend beyond the periphery of the

[0316] In some variations, the analyte monitoring system may provide user status, analyte monitoring device status, and / or other suitable information directly via a user interface on the analyte monitoring device (e.g., a display, indicator lights, etc., as described below). Thus, in contrast to analyte monitoring systems that may simply communicate information to a separate peripheral device (e.g., a mobile phone, etc.), which in turn communicates the information to the user, in some variations, such information may be provided directly by the analyte monitoring device. Advantageously, in some variations, such a user interface on the analyte monitoring device may reduce the need for a user to constantly maintain a separate peripheral device to monitor user status and / or analyte monitoring device status (which may be impractical due to cost, inconvenience, etc.). Additionally, the user interface on the analyte monitoring device may reduce risks associated with loss of communication between the analyte monitoring device and a separate peripheral device, such as the user having an inaccurate understanding of their current analyte levels (e.g., leading the user to believe their analyte levels are high when they are actually low, which may result in the user self-administering an incorrect dose of medication or withholding a therapeutic intervention when this is medically necessary).

[0317] Additionally, the ability to communicate information to a user via the analyte monitoring device itself, independent of a separate peripheral device, may reduce or eliminate the need to maintain compatibility between the analyte monitoring device and a separate peripheral device when such a peripheral device is upgraded (e.g., replaced with a new device model or other hardware, launched with a new version of an operating system or other software, etc.).

[0318] Thus, in some variations, the housing may include a user interface, such as an interface for providing information in a visual, auditory, and / or tactile manner, to provide information regarding the user status and / or the status of the analyte monitoring device and / or other suitable information. Examples of user status that may be communicated via the user interface include information indicative of an analyte measurement at the user (e.g., below a predetermined target analyte measurement threshold or range, within a predetermined target analyte measurement range, above a predetermined target analyte measurement threshold or range, an increase or decrease in the analyte measurement over time, a rate of change of the analyte measurement, other information regarding trends in the analyte measurement, other suitable alerts associated with the analyte measurement, etc.). Examples of analyte monitoring device status that may be communicated via the user interface include a device operating mode (e.g., associated with a device warm-up status, an analyte monitoring status, a battery power status such as low battery, etc.), a device error status (e.g., an operational error, pressure-induced sensing decay, a fault, a failure mode, etc.), a device power status, a device life status (e.g., an expected end of life for the sensor), a status of connectivity between the device and a mobile computing device, and / or the like.

[0319] 29 illustrates another exemplary variation of a microneedle 900 having a generally cylindrical body portion. The microneedle 900 may be similar to the microneedle 700 described above, except as described below. For example, like the microneedle 700, the microneedle 900 may include a cylindrical body portion 912 and a tapered distal portion 914 that terminates in an insulated distal apex 916. The microneedle 900 may further include a ring electrode 920 comprising a conductive material and arranged on the tapered distal portion 914 at a location proximal to (or offset from or spaced apart from) the distal apex 916. Other elements of the microneedle 900 have numbering similar to corresponding elements of the microneedle 700.

[0320] However, compared to microneedle 700, microneedle 900 may have a sharper tip at distal apex 916 and a modified insulating moat 913. For example, distal apex 916 may have a sharper tip angle, such as about 25 degrees to about 45 degrees, and an apex radius of less than about 100 nm, which provides a sharper microneedle profile that may penetrate skin with greater ease, lower velocity, less energy, and / or less trauma. Furthermore, in contrast to insulating moat 713 (which extends through substrate 702 and along the height of microneedle body portion 712 as shown in FIG. 33A), modified insulating moat 913 may extend only through substrate 902 such that the sandwiching structure filling the groove (e.g., produced by DRIE as described above) forms only a buried feature in the substrate. Although the sidewalls of the microneedle 900 are shown in FIG. 29 as extending approximately perpendicular to the substrate plane, it should be understood that the modified insulating moat 913 need not extend the entire height of the microneedle body portion 712, and therefore in some variations the sidewalls of the microneedle 900 may be angled at a non-orthogonal angle relative to the substrate (e.g., the sidewalls may have a slight positive taper of about 1 degree to about 10 degrees or about 5 degrees to about 10 degrees).

[0321] In some variations, the remainder of the microneedle surface 900 (apart from the ring electrode 920) may include insulating material extending from the substrate insulator 904. For example, a layer of insulating material (e.g., SiO) may extend from the front side of the substrate 902 to provide body portion insulation 918 and may further extend up over the proximal edge of the electrode 920, as shown in FIG. 29 . Another region of insulating material may similarly cover the distal edge of the electrode 920 and insulate the distal apex 916. Such regions of insulating material and / or modified insulating moat 913 may help prevent electrical contact between the conductive core 940 and the surrounding substrate 902. Thus, like the microneedle 700, the microneedle 900 may maintain electrical isolation for individual addressability within a microneedle array. In some variations, the process for forming the microneedle 900 may result in higher yields and / or offer lower production costs compared to the process for forming the microneedle 700.

[0322] The microneedle 900 may have any suitable dimensions. By way of example, the microneedle 900 may, in some variations, include a height of about 400 μm to about 600 μm, or about 500 μm. In some variations, the tapered distal portion 914 may have a tip angle of about 25 degrees to about 45 degrees with a tip radius of less than about 100 nm. Additionally, the microneedle may have a shaft diameter of about 160 μm to about 200 μm. FIG. 30 illustrates additional various dimensions of an exemplary variation of a pillar-shaped microneedle with a tapered distal portion and a ring electrode, similar to the microneedle 900 described above.

[0323] While Figures 31A-31C illustrate exemplary variations of microneedle array configurations, it should be understood that these figures are not limiting and that other microneedle configurations (such as different numbers and / or distributions of working, counter, and reference electrodes, and different numbers and / or distributions of active and inactive electrodes) may be suitable in other variations of microneedle arrays.

[0324] 2A schematic of analyte monitoring device 110, electronics system 120 may be integrated within housing 112 such that electronics system 120 may be combined with sensing elements (e.g., a microneedle array) as part of a single unit, in contrast to conventional CGM systems that typically incorporate components in multiple physically distinct units. Further details of exemplary variations of electronics system 120 are described below.

[0325] In some variations, the analyte monitoring device may include one or more PCBs. For example, an analyte monitoring device may include a microneedle array and at least one device PCB, as shown in FIG. 27E. 351 a sensor assembly including: 321 The at least one PCB may include:

[0326] For example, as shown in Figures 27F-27I, the sensor assembly 321 may include a sensor standoff PCB 322 coupled to a connection PCB 324. 331 may be attached to the sensor standoff PCB 322 (e.g., FR-4, PTFE, Rogers 4350B), such as through a soldering process combined with an epoxy underfill for mechanical strength. In some variations, an epoxy skirt is attached to the silicon microneedle array to mitigate sharp edges from the silicon dicing process described above. 331 The epoxy may also provide a transition from the edge of the silicon substrate of the microneedle array silicon to the edge of the PCB 322. Alternatively, the epoxy may be replaced or supplemented by a rubber gasket or equivalent.

[0327] As shown in FIG. 27J, the sensor standoff PCB 322 is, at least in part, connected to the microneedle array. 331 The standoff height of the sensor standoff PCB 322 may act as a standoff that determines the desired distance that the microneedle array protrudes from the housing 310.331 The housing 310 may be selected to help ensure that the sensor standoff PCB 322 is properly inserted into the user's skin. During needle insertion, the bottom surface of the housing 310 wi...

Claims

1. 1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, the housing body comprising a distal opening, the housing body further comprising a mounting portion extending from a proximal end of the housing body toward the distal opening of the housing body; a cuff received within the cavity, the cuff comprising a lumen therethrough; a shuttle slidably received within the lumen, the shuttle configured to releasably retain the analyte monitoring device; a biasing element disposed between the housing and the shuttle, the biasing element configured to bias the shuttle toward the distal opening; Equipped with the engagement between the mount and the shuttle includes contact between a shuttle retaining surface of at least one downwardly extending finger of the mount and a ledge on an outer surface of the shuttle; the applicator is movable between a collapsed configuration, an extended configuration, and a released configuration; In the collapsed configuration, the analyte monitoring device is retained within the shuttle, and a distal edge of the shuttle and the cuff is in a proximal-most position and positioned proximal to the distal opening of the housing body; In the extended configuration, the distal edge of the cuff is in a distal-most position and positioned distal to the distal opening of the housing body, and the shuttle is in an intermediate position and positioned proximal to the distal opening of the housing body; In the released configuration, the analyte monitoring device is released from the shuttle, the distal edge of the cuff is in an intermediate position and positioned distal to the distal opening of the housing body, and the shuttle is in a distal-most position and positioned distal to the distal opening of the housing body.

2. The applicator of claim 1 , further comprising a base configured to removably couple to the housing body at the distal opening.

3. The applicator of claim 1 , further comprising a friction ring releasably engageable with the cuff.

4. 3. The applicator of claim 2, wherein the housing body further comprises a recess formed in a distal surface of the housing body, the base further comprises a restraining arm configured to be releasably received in the recess in the housing body, the base further comprises a wall disposed circumferentially around a microneedle enclosure releasably coupled to a proximal surface of the base, the microneedle enclosure releasably engaging the analyte monitoring device, the analyte monitoring device comprising a microneedle array oriented away from the proximal end of the housing body, and the microneedle enclosure configured to enclose the microneedle array when engaged with the analyte monitoring device.

5. 10. The applicator of claim 1, further comprising a locking member at least partially received within at least one side opening of the housing body and releasably engageable with the cuff.

6. 6. The applicator of claim 5, wherein when the applicator is in the collapsed configuration, the locking member engages the cuff, thereby preventing the cuff from moving distally toward the distal opening of the housing body.

7. The applicator of claim 6 , wherein engagement between the locking member and the cuff comprises contact between an upper edge of the locking member and a retention edge of the cuff.

8. 2. The applicator of claim 1, wherein the cuff includes one or more tracks, and when the applicator is moved from the collapsed configuration to the extended configuration and the released configuration, one or more corresponding tracking protrusions on the shuttle can be slidably engaged within the one or more tracks, thereby maintaining alignment between the cuff and the shuttle.

9. 6. The applicator of claim 5, wherein actuation of the locking member releases engagement between the locking member and the cuff, thereby allowing the cuff to move toward the distal opening of the housing body and the applicator to move from the collapsed configuration to the extended configuration.

10. The applicator of claim 9 , wherein when the locking member is actuated, the shuttle moves toward the distal opening of the housing body.

11. 11. The applicator of claim 10, further comprising a base configured to removably couple to the housing body at the distal opening, wherein movement of the cuff toward the distal opening of the housing body axially displaces the base relative to the housing body.

12. 3. The applicator of claim 2, further comprising a microneedle enclosure releasably coupled to a proximal surface of the base and releasably engageable with the analyte monitoring device, the microneedle enclosure comprising a cavity and a capsule slidably received within the cavity, the capsule enclosing a microneedle array of the analyte monitoring device when the microneedle enclosure is engaged with the analyte monitoring device and when the applicator is in the collapsed configuration, the microneedle array facing away from the proximal end of the housing body.

13. The applicator of claim 2 , wherein the base comprises a restraining arm configured to be releasably received within a recess in the housing body.

14. The applicator of claim 2 , wherein the base further comprises a retaining arm configured to be received between the cuff and an inner surface of the housing body.

15. 3. The applicator of claim 2, further comprising a microneedle enclosure releasably coupled to a proximal surface of the base and releasably engageable with the analyte monitoring device, the microneedle enclosure configured to enclose a microneedle array of the analyte monitoring device when the microneedle enclosure is engaged with the analyte monitoring device and when the applicator is in the collapsed configuration, and when the applicator is in the extended configuration, the microneedle enclosure does not enclose the microneedle array and the microneedle array is directed away from the proximal end of the housing body.

16. 4. The applicator of claim 3, wherein when the applicator is in the extended configuration, the friction ring is engaged with the cuff, thereby preventing the cuff from moving distally relative to the distal opening of the housing body.

17. The applicator of claim 3 , wherein the mounting portion is releasably engaged with the friction ring when the applicator is in the extended configuration.

18. 18. The applicator of claim 17, wherein engagement between the mounting portion and the friction ring comprises contact between a ring retaining surface of at least one downwardly extending finger of the mounting portion and a protrusion of the friction ring.

19. The applicator of claim 1 , wherein the mounting portion is releasably engaged with the shuttle when the applicator is in the extended configuration.

20. 20. The applicator of claim 19, wherein engagement between the mounting portion and the shuttle comprises contact between a shuttle retaining surface of at least one downwardly extending finger of the mounting portion and a ledge on an outer surface of the shuttle.

21. The applicator of claim 2 , wherein the applicator is moved from the extended configuration to the released configuration after the base is removed from the housing.

22. 20. The applicator of claim 18, wherein when the applicator is moved to the released configuration, a ring retention surface of the at least one downwardly extending finger of the mounting portion disengages from the protrusion of the friction ring.

23. 21. The applicator of claim 20, wherein when the applicator is moved to the released configuration, the shuttle retaining surface of the at least one downwardly extending finger of the mounting portion disengages from the ledge on the outer surface of the shuttle.

24. The applicator further comprises a friction ring releasably engageable with the cuff; when the applicator is in the extended configuration, the mounting portion is releasably engaged with the friction ring; 24. The applicator of claim 23, wherein when the applicator is moved to the released configuration, disengagement of the friction ring from the mounting portion causes the at least one downwardly extending finger of the mounting portion to bend away from the shuttle, thereby releasing the shuttle retaining surface of the at least one downwardly extending finger from the shuttle member of the shuttle.

25. 2. The applicator of claim 1, wherein when the applicator is in the released configuration, one or more tracking protrusions on the shuttle engage with a shuttle flex surface of the cuff, thereby preventing further movement of the shuttle relative to the cuff and away from the proximal end of the housing body.

26. 1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, the housing body comprising a distal opening, the housing body further comprising a mounting portion extending from a proximal end of the housing body toward the distal opening of the housing body; a cuff received within the cavity, the cuff comprising a lumen therethrough; a shuttle slidably received within the lumen, the shuttle configured to releasably retain the analyte monitoring device; a biasing element disposed between the housing and the shuttle, the biasing element configured to bias the shuttle toward the distal opening; Equipped with the engagement between the mount and the shuttle includes contact between a shuttle retaining surface of at least one downwardly extending finger of the mount and a ledge on an outer surface of the shuttle; the applicator is movable between a collapsed configuration, an extended configuration, and a released configuration; In the collapsed configuration, the analyte monitoring device is retained within the shuttle, and a distal edge of the shuttle and the cuff is in a proximal-most position and positioned proximal to the distal opening of the housing body; In the extended configuration, the distal edge of the cuff is in a distal-most position and positioned distal to the distal opening of the housing body, and the shuttle is in an intermediate position and positioned proximal to the distal opening of the housing body; In the released configuration, the analyte monitoring device is released from the shuttle, the distal edge of the cuff is in an intermediate position and positioned distal to the distal opening of the housing body, and the shuttle is in a distal-most position and positioned distal to the distal opening of the housing body.

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