Apparatus, system and method for improving patch performance for medical devices

Abstract

The present embodiments relate generally to apparatus, systems, and methods for placing a medical device on the skin of a recipient. The apparatus, systems, and methods may be directed to removing a liner for a medical device so that the medical device can be coupled to the skin of the recipient. The medical device may include an on-skin wearable medical device.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Application No. 63 / 261,910, filed September 30, 2021, the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION Apparatus, system, and method for placing and attaching a medical device to a recipient's skin. More specifically, apparatus, system, and method for placing and attaching a transcutaneous analyte sensor to a recipient are provided. [Background technology]

[0003] Diabetes mellitus is a disorder in which the pancreas cannot make enough insulin (type 1, or insulin-dependent) and / or insulin is ineffective (type 2, or non-insulin-dependent). In the diabetic state, the victim suffers from hyperglycemia, which can lead to a number of physiological disorders associated with deterioration of small blood vessels, such as kidney failure, skin ulcers, or bleeding into the vitreous of the eye. A hypoglycemic reaction (hypoglycemia) can be precipitated by inadvertent overdosing of insulin or after normal administration of insulin or glucose-lowering agents accompanied by abnormal exercise or inadequate food intake.

[0004] Traditionally, people with diabetes carry self-monitoring blood glucose (SMBG) monitors, which typically require an uncomfortable finger prick. Due to a lack of comfort and convenience, people with diabetes typically measure their glucose levels only two to four times per day. Unfortunately, these time intervals are spread so far apart that people with diabetes may not know about their hyperglycemic or hypoglycemic condition until it is too late, sometimes resulting in dangerous side effects. Alternatively, glucose levels can be continuously monitored by a measurement system that includes an on-skin sensor assembly. The sensor assembly may have a wireless transmitter that transmits measurement data to a receiver, which can process and display information based on the measurements.

[0005] The process of applying the sensor to a person is important for such a system to be effective and easy to use: the application process should result in the on-skin sensor assembly being attached to a person, with the on-skin sensor assembly being able to sense analyte (e.g., glucose) level information, communicate the sensed data to a transmitter, and transmit the analyte level information to a receiver.

[0006] Exemplary prior art systems are disclosed, for example, in U.S. Patent Application Publication Nos. 2014 / 0088389, 2013 / 0267813, and 2018 / 0368771, which are owned by the assignee of the present application and are incorporated herein by reference in their entireties.

[0007] This Background is provided to introduce a brief background to the Summary and Detailed Description that follow. This Background is not intended to aid in determining the scope of the claimed subject matter, nor should it be deemed to limit the claimed subject matter to implementations that solve any or all of the disadvantages or problems presented above. Summary of the Invention

[0008] The present systems and methods relate to apparatus, systems, and methods for positioning and attaching a medical device to a recipient's skin. More particularly, apparatus, systems, and methods are provided for positioning and attaching a transcutaneous analyte sensor to a recipient. Various embodiments of the present systems, devices, and methods may have several features, no one of which is solely responsible for its desirable attributes. Without limiting the scope of the present embodiments as expressed by the claims that follow, their more prominent features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled "Detailed Description of the Invention," one will understand how the features of the present embodiments provide the advantages described herein. [Means for solving the problem]

[0009] In a first aspect, a system is provided. The system may include an on-skin wearable medical device configured to be placed on the skin and including a patch having a first surface for engaging the skin. The system may include a liner positioned on the first surface. The system may include an applicator housing configured to hold the on-skin wearable medical device. The system may include a liner removal component configured to engage with and at least partially separate the liner from the first surface when the liner removal component is at least partially withdrawn from the first surface.

[0010] Implementations of the embodiments may include one or more of the following: The applicator housing may be configured to be gripped by a user. The one or more holding elements may be for releasing the on-skin wearable medical device from the applicator housing. The insertion assembly may be for inserting at least a portion of the on-skin wearable medical device into the skin. The insertion assembly may include at least one spring for inserting at least a portion of the on-skin wearable medical device into the skin. The insertion assembly may be configured to insert the needle into the skin. The retraction assembly may be for retracting the needle from the skin. The applicator housing may include an internal cavity for holding the on-skin wearable medical device. The liner removal component may include a body configured to extend axially within the internal cavity. The applicator housing may include an opening at an end portion of the internal cavity for disposing the on-skin wearable medical device therein. The liner removal component may include a first portion for engaging the liner and a second portion axially spaced from the first portion. The second portion may be configured to be positioned in the opening. The applicator housing includes a distal end portion and a proximal end portion, the opening being located at the distal end portion of the applicator housing, and at least a portion of the liner removal component configured to extend outside the applicator housing from the second portion to a third portion located at the proximal end portion of the applicator housing. The liner removal component may include an opening in the third portion configured to allow the liner removal component to pass through the applicator housing. A cover may be located at the opening in the third portion to cover the applicator housing. The liner removal component may include a first portion for engaging the liner and a second portion spaced from the first portion. The second portion may be configured to extend over an outer surface of the applicator housing. The first portion may be configured to rotate relative to the second portion. The second portion may be configured to separate from the applicator housing. The second portion may be configured to unscrew from the applicator housing to at least partially separate the liner removal component from the applicator housing.The liner removal component may include one or more guides configured to prevent the first portion from rotating relative to the applicator housing when the second portion rotates relative to the first portion. The one or more guides may be configured to engage an inner surface of the applicator housing and prevent rotation of the first portion relative to the applicator housing. The liner removal component may include one or more bearing surfaces configured to couple the first portion to the second portion. The liner removal component may include one or more bearing surfaces configured to allow the first portion to rotate relative to the second portion. The liner removal component may include one or more rotation couplers spaced apart from the one or more bearing surfaces with a gap, the one or more rotation couplers configured to rotate relative to the one or more bearing surfaces. Rotation of the first portion relative to the second portion may cause the one or more rotation couplers to contact the one or more bearing surfaces. A first one of the rotation couplers may be configured to contact the one or more bearing surfaces before a second one of the rotation couplers. The one or more rotation couplers may include one or more arms. At least a portion of the liner removal component may be configured to be assembled with one or more arms deflected by the second portion. The gripping portion may be positioned on the second portion and configured to be gripped by a user to at least partially withdraw the liner removal component from the first surface of the on-skin wearable medical device. The engaging portion may be positioned on the second portion and configured to engage a portion of the applicator housing to hold the liner removal component relative to the applicator housing. The engaging portion may be configured to be rotated relative to the applicator housing to release the liner removal component from the applicator housing. The height of the first portion relative to the second portion may be configured to be adjustable. The liner removal component may include a cam surface configured to adjust the height of the first portion relative to the second portion. The liner removal component may include one or more deflectable arms connecting the first portion to the second portion. The one or more deflectable arms may be configured to deflect to adjust the height of the first portion relative to the second portion.The one or more deflectable arms may be arranged in a spiral configuration. The one or more deflectable arms may be configured to deflect to accommodate a liner removal component coupled to the applicator housing. The liner removal component may comprise a base for the applicator housing. The applicator housing may include an internal cavity for holding the on-skin wearable medical device, and the liner removal component covers the internal cavity. At least a portion of the liner removal component may comprise packaging for the applicator housing. The liner removal component may include a cover for covering at least a portion of the first surface. The cover may include an opening for the needle to pass through. The opening may include a puncture layer for the needle to pass through. The liner removal component may include a sheath for covering the needle. The liner removal component may include a spring configured to press against the on-skin wearable medical device, the spring configured to move the liner removal component away from the on-skin wearable medical device to at least partially separate the liner from the first surface. The liner may include one or more bonding surfaces for bonding to the liner removal component. The one or more bonding surfaces may include an adhesive surface. The liner may include an opening for passing a needle. The one or more bonding surfaces may surround the opening. The liner may include a central portion proximate the opening and an edge portion proximate an edge of the liner, and the one or more bonding surfaces are located in one or more of the central portion or the edge portion. The one or more bonding surfaces may include a plurality of sections. The one or more bonding surfaces may be located in the central portion and the edge portion. The one or more bonding surfaces may include one or more elongated strips. The liner may include one or more bonding regions for bonding to a liner removal component. A needle may be driven into the skin to position the on-skin wearable medical device on the skin. The on-skin wearable medical device may include a transdermal analyte sensor. The first surface may be an adhesive surface. The patch may include a piercing layer for passing a needle. The piercing layer may be configured to allow the transdermal analyte sensor to pass through.The liner removal component may be configured to asymmetrically separate the liner from the first surface when the liner removal component is at least partially withdrawn from the first surface. The liner removal component may be configured to peel the liner from the first surface when the liner removal component is at least partially withdrawn from the first surface. The liner removal component may include a cap. The liner removal component may include a sheath for sealing at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. At least a portion of the sheath may include a layer configured to allow sterilizing gas to permeate through the layer and contact at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. The sheath may surround an internal cavity, and the system further includes a gasket configured to seal the internal cavity. The sheath may surround an internal cavity, and the system further includes an adhesive configured to seal the internal cavity. The liner removal component may include an engagement portion configured to engage an outer surface of the applicator housing to hold the liner removal component relative to the applicator housing, the engagement portion configured to disengage from the outer surface when the liner removal component is pulled axially relative to the applicator housing. The on-skin wearable medical device may further include a stabilizer configured to stabilize a transcutaneous analyte sensor of the on-skin wearable medical device within the needle channel. The on-skin wearable medical device may include an optical sensor, and the liner removal component configured to shield the optical sensor from light.

[0011] In a second aspect, a method includes at least partially withdrawing a liner removal component from a first surface of an on-skin wearable medical device to at least partially separate the liner from the first surface, where the on-skin wearable medical device is held by an applicator housing, and placing the on-skin wearable medical device from the applicator housing onto the skin with the first surface in contact with the skin.

[0012] Implementations of embodiments may include one or more of the following: The on-skin wearable medical device may be held within an internal cavity of the applicator housing. The liner removal component may include a body extending axially within the internal cavity. The applicator housing may include an opening at an end portion of the internal cavity for placement of the on-skin wearable medical device, with at least a portion of the liner removal component positioned in the opening. The liner removal component may include a first portion axially spaced from a second portion, the first portion engaging the liner. The method may include separating the second portion from the applicator housing. The method may include gripping a gripping portion positioned on the second portion to at least partially withdraw the liner removal component from the first surface. The method may include rotating the gripping portion relative to the applicator housing to at least partially release the liner removal component from the applicator housing. The first portion may be configured to rotate relative to the second portion. The method may include unthreading the second portion from the applicator housing to at least partially release the liner removal component from the applicator housing. The liner removal component may include one or more guides configured to prevent the first portion from rotating relative to the applicator housing when the second portion rotates relative to the first portion. The liner removal component may include one or more bearing surfaces configured to couple the first portion to the second portion. The liner removal component may include one or more bearing surfaces configured to allow the first portion to rotate relative to the second portion. The liner removal component may include one or more rotation couplers spaced apart from the one or more bearing surfaces with a gap, the one or more rotation couplers configured to rotate relative to the one or more bearing surfaces. Rotation of the first portion relative to the second portion may cause the one or more rotation couplers to contact the one or more bearing surfaces. A first one of the rotation couplers may contact the one or more bearing surfaces before a second one of the rotation couplers. The one or more rotation couplers may include one or more arms. The height of the first portion relative to the second portion may be configured to be adjustable.The liner removal component may include one or more deflectable arms connecting the first portion to the second portion. The on-skin wearable medical device may include a transcutaneous analyte sensor. The first surface may be an adhesive surface. The on-skin wearable medical device may include a patch having a first surface. The patch may include a puncturing layer for passage of a needle. The puncturing layer may be configured for passage of the transcutaneous analyte sensor. The liner may include one or more bonding surfaces for coupling to the liner removal component. The liner may include an opening for passage of the transcutaneous analyte sensor, a central portion proximate the opening, and an edge portion proximate an edge of the liner, wherein the one or more bonding surfaces are positioned on one or more of the central portion or the edge portion. The method may include inserting a needle from the applicator housing into the skin. The method may include retracting the needle from the skin into the applicator housing. The method may include coupling the liner removal component to the applicator housing after the needle is retracted from the skin into the applicator housing. At least a portion of the liner removal component may bend to accommodate the liner removal component coupled to the applicator housing. The method may include peeling the liner from the first surface when the liner removal component is at least partially withdrawn from the first surface. The liner removal component may include a cap. The liner removal component may include a sheath for sealing at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. At least a portion of the sheath may include a layer configured to allow sterilizing gas to permeate through the layer and contact at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. The sheath may surround an internal cavity, and a gasket seals the internal cavity. The sheath may surround the internal cavity and an adhesive sealing the internal cavity. The liner removal component may include an engagement portion that engages with an outer surface of the applicator housing to hold the liner removal component relative to the applicator housing, and the method further includes pulling the liner removal component axially relative to the applicator housing to disengage the engagement portion from the outer surface.The stabilizer can stabilize a transcutaneous analyte sensor of the on-skin wearable medical device within the needle channel. The on-skin wearable medical device may include an optical sensor, and the liner removal component is configured to shield the optical sensor from light. The method may include withdrawing the optical sensor removal component from the optical sensor to expose the optical sensor to light.

[0013] In a third aspect, an on-skin wearable medical device system includes a housing, a transcutaneous analyte sensor coupled to the housing, a patch coupled to the housing and including a first surface for engaging the skin, a liner having a proximal surface contacting the first surface and a distal surface facing opposite the proximal surface, and one or more adhesive surfaces on the distal surface configured to engage an object to at least partially pull the liner from the first surface of the patch.

[0014] Implementations of the embodiments may include one or more of the following: The patch may include an opening for passage of the transcutaneous analyte sensor. The patch may include a puncturing layer for passage of the transcutaneous analyte sensor. The puncturing layer may be configured for passage of a needle. The patch may include multiple layers, the puncturing layer being a first layer of the multiple layers positioned adjacent to a second layer of the multiple layers. The one or more adhesive surfaces may include multiple segments. The one or more adhesive surfaces may include one or more dots. The one or more adhesive surfaces may include one or more dots. The one or more adhesive surfaces may include multiple strips. The one or more adhesive surfaces may cover the entire distal surface of the liner. The patch may include a skirt portion extending radially outward from the housing, the liner including a skirt portion covering the skirt portion of the patch, the one or more adhesive surfaces being positioned on the skirt portion of the liner. The liner may include an opening for passage of the transcutaneous analyte sensor. The one or more adhesive surfaces may surround the opening. The liner may include a central portion proximate the opening and an edge portion proximate the edge of the liner, with one or more adhesive surfaces located on one or more of the central portion or the edge portion. The one or more adhesive surfaces may be located on the edge portion. The one or more adhesive surfaces may be located on the central portion and the edge portion. The liner may include one or more curved notches extending radially outward from the opening in the liner. The liner may include multiple layers. The liner may include a layer having a first portion and a second portion, with the first portion folded over the second portion. Both the patch and the liner may include an opening for passing a needle.

[0015] In a fourth aspect, an on-skin wearable medical device system comprises a housing and a patch coupled to the housing and including a first surface for engaging the skin, the patch including a puncturing layer for passage of one or more of the transcutaneous analyte sensor or an insertion element of the transcutaneous analyte sensor.

[0016] Implementations of the embodiments may include one or more of the following: The puncturing layer may be configured to retain the transcutaneous analyte sensor in the channel of the insertion element. The puncturing layer may be configured to form a seal around the insertion element to retain the transcutaneous analyte sensor in the channel of the insertion element. The puncturing layer may be configured to stabilize the transcutaneous analyte sensor in a horizontal dimension from dislodging from the channel of the insertion element. The patch may include multiple layers, the puncturing layer being a first layer of the multiple layers layered adjacent to a second layer of the multiple layers. The second layer may include a first surface, the first layer being sandwiched between the second layer and the housing. The multiple layers may include a third layer sandwiched between the first layer and the second layer, the third layer including an adhesive surface for adhering the patch to the housing. The first layer may include a puncturing portion and a support portion, the puncturing portion configured to receive one or more of the transcutaneous analyte sensor or an insertion element of the transcutaneous analyte sensor, and the support portion positioned radially outward from the puncturing portion and configured to overlap another layer of the plurality of layers. The support portion may include an elongated arm extending radially outward from the puncturing portion. The housing may include a cavity for receiving a portion of the transcutaneous analyte sensor, and at least a portion of the puncturing layer extends along the cavity. The puncturing layer may include at least one elongated arm for forming at least one passage for moisture transport. The puncturing layer may be made of a hydrophobic material. The puncturing layer may be configured to allow the insertion element to be withdrawn through the puncturing layer while the transcutaneous analyte sensor remains passed through the puncturing layer. The first surface may include an adhesive surface. The system may further include an applicator housing configured to hold the housing.

[0017] In a fifth aspect, an on-skin wearable medical device system comprises a housing, a transcutaneous analyte sensor coupled to the housing, and a patch coupled to the housing and including a first surface for engaging the skin, at least a portion of the patch including a spiral configured to extend around an insertion element of the transcutaneous analyte sensor and stabilize a position of the transcutaneous analyte sensor relative to the insertion element.

[0018] Implementations of embodiments may include one or more of the following: The spiral body may be configured to stabilize the transcutaneous analyte sensor in the horizontal dimension from dislodging from the channel of the insertion element. The spiral body may be configured to contact the transcutaneous analyte sensor to stabilize the transcutaneous analyte sensor in the horizontal dimension from dislodging from the channel of the insertion element. The spiral body may be configured to move from an extended position to a retracted position, wherein the spiral body in the extended position protrudes from the first surface and the spiral body in the retracted position is flush with or retracted from the first surface. The spiral body may have a helical shape in the extended position and a flat coil shape in the retracted position.

[0019] In a sixth aspect, an on-skin wearable medical device system comprises a transcutaneous analyte sensor, a housing including a cavity for receiving a portion of the transcutaneous analyte sensor, a patch coupled to the housing and including a first surface for engaging the skin, and a stabilizer configured to be positioned within the cavity, the stabilizer configured to stabilize the position of the transcutaneous analyte sensor relative to an insertion element of the transcutaneous analyte sensor.

[0020] Implementations of embodiments may include one or more of the following: The stabilizing body may be configured to stabilize the transcutaneous analyte sensor in the horizontal dimension from dislodging from the channel of the insertion element. The stabilizing body may be configured to contact the transcutaneous analyte sensor to stabilize the transcutaneous analyte sensor in the horizontal dimension from dislodging from the channel of the insertion element. The stabilizing body may include an insert for the cavity. The stabilizing body may include foam.

[0021] In a seventh aspect, a system includes an on-skin wearable medical device configured to be placed on the skin and including a transcutaneous analyte sensor and a patch having a first surface for engaging the skin, an applicator housing having a cavity for holding the on-skin wearable medical device therein, a cap for the cavity, and a stabilizer coupled to the cap, the stabilizer including a support surface configured to stabilize the position of the transcutaneous analyte sensor relative to an insertion element of the transcutaneous analyte sensor.

[0022] Implementations of embodiments may include one or more of the following: The stabilizing body may be configured to stabilize the transcutaneous analyte sensor in a horizontal dimension from dislodging from the channel of the insertion element; The bearing surface may include a curved bearing surface; The cap may be configured to couple to the applicator housing and to be unscrewed from the applicator housing for separation from the applicator housing, the bearing surface being configured to rotate with the cap relative to the transcutaneous analyte sensor when the cap is unscrewed from the applicator housing; The stabilizing body may have a conical shape.

[0023] In an eighth aspect, an on-skin wearable medical device system comprises a housing including a distal surface configured to face the skin, a transcutaneous analyte sensor coupled to the housing, a patch coupled to the housing and including a first surface for engaging the skin, the patch positioned distal to the housing, and one or more moisture passages configured to remove moisture located distal to the housing.

[0024] Implementations of the embodiments may include one or more of the following: The one or more moisture passageways may be configured to remove moisture located proximate an insertion site of the transcutaneous analyte sensor into the skin. The housing may include an outer periphery, and the one or more moisture passageways are configured to remove moisture in a direction toward the outer periphery of the housing. The one or more moisture passageways may be configured to remove moisture located between the patch and a distal surface of the housing. The distal surface of the housing may include at least one channel forming at least a portion of the one or more moisture passageways. The patch may include at least one channel forming at least a portion of the one or more moisture passageways. The housing may include an outer periphery, and the at least one channel extends in a direction from an area of ​​the patch proximate an insertion site of the transcutaneous analyte sensor into the skin toward the outer periphery. The patch may include multiple layers, and a first layer of the multiple layers spaces a second layer of the multiple layers from the distal surface of the housing to form the one or more moisture passageways. The first layer may include one or more elongated arms that spaces a second layer from the distal surface of the housing to form the one or more moisture passageways. The housing may include an outer periphery, and at least one of the one or more elongated arms may extend from a region of the patch proximate the skin insertion site of the transcutaneous analyte sensor toward the outer periphery. The one or more elongated arms may include at least two intersecting elongated arms. At least a portion of the first layer may include a V-shape. The first layer may include a puncturing layer through which one or more of the transcutaneous analyte sensor or the insertion element of the transcutaneous analyte sensor pass. The patch may include a third layer, the third layer including the first surface. The one or more moisture passageways may be configured to wick moisture distal to the housing.

[0025] In a ninth aspect, an on-skin wearable medical device system comprises a housing, a transcutaneous analyte sensor coupled to the housing, a patch coupled to the housing and including a first surface for engaging the skin, and an antimicrobial agent coupled to at least a portion of the on-skin wearable medical device system.

[0026] Implementations of embodiments may include one or more of the following: The antimicrobial agent may comprise at least a portion of a surface of one or more of the housing, the transdermal analyte sensor, or the patch. The antimicrobial agent may be coupled to a first surface of the patch. The housing may include a distal surface for facing the skin, and the antimicrobial agent is coupled to a second surface of the patch opposite the first surface and facing the distal surface of the housing. The antimicrobial agent may be coupled to an adhesive for coupling the patch to the housing. The patch may include a piercing layer through which one or more of the transdermal analyte sensor or the insertion elements of the transdermal analyte sensor pass, and the antimicrobial agent is coupled to the piercing layer. The housing may include an outer periphery, and the patch includes a skirt positioned radially outward from the periphery, and the antimicrobial agent is coupled to the skirt. The antimicrobial agent may be positioned proximate to the insertion site of the transdermal analyte sensor into the skin. The antimicrobial agent may include one or more of iodine, silver, or chlorhexidine gluconate. The antimicrobial agent may include an antimicrobial adhesive.

[0027] In a tenth aspect, an on-skin wearable medical device system comprises a housing, a transcutaneous analyte sensor coupled to the housing, and a patch including a first surface for engaging the skin, the patch being coupled to the housing by adhesive only.

[0028] Implementations of the embodiments may include one or more of the following: The housing may include a distal surface configured to face the skin, and the adhesive is positioned between the patch and the distal surface of the housing. The patch may include multiple layers. The housing may include an outer periphery, and the multiple layers may include a first layer and a second layer, the first layer having a first surface and the second layer overlying the first layer to form a skirt positioned radially outward of the outer periphery. The multiple layers may include a first layer and a second layer, the first layer having a first surface, and the second layer positioned between the first layer and the housing and including an adhesive. The first layer may include an adhesive for engaging the backing and the skin, and the second layer may include an adhesive for bonding to the first layer, a breathable carrier layer, and an adhesive for bonding the patch to the housing. The housing may include an outer periphery, and the patch does not extend outside the periphery of the housing. The periphery of the patch may be recessed from the periphery of the housing. The patch may include a scrim. The patch may include a plurality of perforations.

[0029] In an eleventh aspect, a method of manufacturing an on-skin wearable medical device. The method may include providing a housing for the on-skin wearable medical device, the housing configured to couple to a transcutaneous analyte sensor, and coupling a patch including a first surface for engaging the skin to the housing using only an adhesive.

[0030] Implementations of the embodiments may include one or more of the following: The housing may include a distal surface configured to face the skin, and the method further includes pressing an adhesive between the patch and the distal surface. The patch may include multiple layers. The housing may include an outer periphery, and the multiple layers may include a first layer and a second layer, the first layer having a first surface and the second layer overlying the first layer to form a skirt configured to be positioned radially outward of the outer periphery. The multiple layers may include a first layer and a second layer, the first layer having a first surface and the second layer configured to be positioned between the first layer and the housing and including an adhesive. The first layer may include an adhesive for engaging the backing and the skin, and the second layer includes an adhesive for bonding to the first layer, a breathable carrier layer, and an adhesive for bonding the patch to the housing. The housing may include an outer periphery, and the patch is configured not to extend outside the outer periphery of the housing. The outer periphery of the patch may be configured to be recessed from the outer periphery of the housing. The patch may include a scrim.The patch may include a plurality of perforations.

[0031] In further aspects and embodiments, the features of the methods and various aspects described above are formulated with respect to a system, as in the various aspects, having an applicator configured to perform the method features. Any of the features of any of the embodiments of the aspects, including but not limited to any of the embodiments of any of the first through eleventh aspects mentioned above, are applicable to all other aspects and embodiments identified herein, including but not limited to any of the embodiments of any of the first through eleventh aspects mentioned above. Furthermore, any of the features of the embodiments of the various aspects, including but not limited to any of the embodiments of any of the first through eleventh aspects mentioned above, may be independently combined in any manner, partially or wholly, with other embodiments described herein; for example, one, two, or three or more embodiments may be combined in whole or in part. Furthermore, any of the features of the embodiments of the various aspects, including but not limited to any of the embodiments of any of the first through eleventh aspects mentioned above, may be optional with respect to other aspects or embodiments. Any aspect or embodiment of the method may be performed by a system or apparatus of another aspect or embodiment, and any aspect or embodiment of the system or apparatus may be configured to perform the method of another aspect or embodiment, including, but not limited to, any embodiment of any of the first to eleventh aspects referred to above.

[0032] This Summary is provided to introduce a selection of concepts in a simplified form. The concepts are further described in the Detailed Description. Elements or steps other than those described in this Summary are possible, and no element or step is necessarily required. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended for use as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure. [Brief explanation of the drawings]

[0033] These and other features, aspects, and advantages are described below with reference to the drawings, which are intended to illustrate, but not limit, the disclosure, in which like reference characters indicate corresponding features consistently throughout like embodiments. [Figure 1] 1 illustrates a schematic diagram of a continuous analyte sensor system. [Figure 2A] 1 illustrates a top perspective view of an on-skin sensor assembly. [Figure 2B] 2B illustrates a bottom perspective view of the on-skin sensor assembly of FIG. 2A in an assembled state. [Figure 2C] 2B illustrates a cross-sectional view of the on-skin sensor assembly of FIG. 2A in an assembled state. [Figure 3] 1 illustrates an assembled perspective view of an on-skin sensor assembly. [Figure 4] 1 illustrates a perspective view of an on-skin sensor assembly. [Figure 5] 1 illustrates a perspective view of an applicator system for an on-skin sensor assembly of an analyte sensor system. [Figure 6] 6 illustrates an exploded perspective view of the applicator system of FIG. 5. [Figure 7] 5 and 6, taken along section line A-A' of FIG. 5, illustrate several cross-sectional views of the applicator system of FIGS. 5 and 6 in operation. [Figure 8] 5 and 6, taken along section line A-A' of FIG. 5, illustrate several cross-sectional views of the applicator system of FIGS. 5 and 6 in operation. [Figure 9] 5 and 6, taken along section line A-A' of FIG. 5, illustrate several cross-sectional views of the applicator system of FIGS. 5 and 6 in operation. [Figure 10] 7 illustrates several cross-sectional views of the applicator system of FIGS. 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 11] 7 illustrates several cross-sectional views of the applicator system of FIGS. 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 12]7 illustrates several cross-sectional views of the applicator system of FIGS. 5 and 6, taken along section line BB' of FIG. 5, in operation. [Figure 13] 7 illustrates an enlarged view of some features of the applicator system of FIGS. 5 and 6. [Figure 14] 7 illustrates an enlarged view of some features of the applicator system of FIGS. 5 and 6. [Figure 15] 7 illustrates an enlarged view of some features of the applicator system of FIGS. 5 and 6. [Figure 16] 7 illustrates an enlarged view of some features of the applicator system of FIGS. 5 and 6. [Figure 17] 7 illustrates a perspective, partial cutaway view of the needle carrier assembly, hub, and on-skin sensor assembly of the applicator system of FIGS. 5 and 6. [Figure 18] 7 illustrates a cross-sectional view of the hub and on-skin sensor assembly of the applicator system of FIGS. 5 and 6. [Figure 19] 7 illustrates a top view of a portion of the needle carrier assembly and hub of FIGS. 5 and 6; FIG. [Figure 20A] 10 illustrates a perspective view of a locking feature for a needle for use in an applicator for an analyte sensor system. [Figure 20B] 10 illustrates a perspective view of a locking feature for a needle for use in an applicator for an analyte sensor system. [Figure 21] 10 illustrates several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, as well as various features and operating positions. [Figure 22] 10 illustrates several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, as well as various features and operating positions. [Figure 23] 10 illustrates several cross-sectional views of yet another applicator for an on-skin sensor assembly of an analyte sensor system, as well as various features and operating positions. [Figure 24] 24 illustrates perspective views of various features of the applicator system of FIGS. 21-23. [Figure 25A] 10 illustrates a cross-sectional view of yet another sensor holding element for an applicator for an analyte sensor system. [Figure 25B] 10 illustrates a cross-sectional view of yet another sensor holding element for an applicator for an analyte sensor system. [Figure 26A] 1 illustrates a cross-sectional view of the system. [Figure 26B] 1 illustrates a perspective view of a liner removal component. [Figure 26C] 1 illustrates a perspective view of a holder. [Figure 26D] 1 illustrates a schematic cross-sectional view of a liner on a liner removal component. [Figure 26E] 26B illustrates a perspective view of the system shown in FIG. 26A. [Figure 26F] 26B illustrates a perspective view of the system shown in FIG. 26A. [Figure 26G] 1 illustrates a perspective view of a liner removal component. [Figure 27A] 1 illustrates a cross-sectional view of the system. [Figure 27B] 1 illustrates a top perspective view of a liner removal component. [Figure 27C] FIG. 27C illustrates a bottom perspective view of the liner removal component shown in FIG. 27B. [Figure 28A] 1 illustrates a top perspective view of a liner removal component. [Figure 28B] FIG. 28B illustrates a bottom perspective view of the liner removal component shown in FIG. 28A. [Figure 28C] 28B illustrates a side view of the liner removal component shown in FIG. 28A. [Figure 28D] 28B illustrates a cross-sectional view of the liner removal component shown in FIG. 28A along with a schematic diagram of an on-skin wearable medical device positioned thereon. [Figure 28E] 28B illustrates a cross-sectional view of the liner removal component shown in FIG. 28A along with a schematic diagram of an on-skin wearable medical device positioned thereon. [Figure 29A] 1 illustrates a cross-sectional view of the system. [Figure 29B] 1 illustrates a top view of a liner removal component. [Figure 29C] 29B illustrates a perspective view of the system shown in FIG. 29A. [Figure 29D] 29B illustrates a cross-sectional view of the system shown in FIG. 29A. [Figure 29E] 1 illustrates a perspective view of a liner. [Figure 29F] 29E illustrates a schematic cross-sectional view of the liner shown in FIG. 29E. [Figure 30A] 1 illustrates a cross-sectional view of the system. [Figure 30B] FIG. 30B illustrates a bottom perspective view of a portion of the liner removal component shown in FIG. 30A. [Figure 30C] FIG. 30B illustrates a perspective cross-sectional view of the liner removal component shown in FIG. 30A. [Figure 30D] FIG. 30B illustrates a bottom perspective cross-sectional view of the liner removal component shown in FIG. 30A. [Figure 30E] 30B illustrates a cross-sectional view of the system shown in FIG. 30A. [Figure 30F] 1 illustrates a perspective cross-sectional view of a liner removal component. [Figure 30G] FIG. 30F illustrates a perspective view of the liner removal component shown in FIG. 30F. [Figure 30H] FIG. 30F illustrates a top perspective view of the liner removal component shown in FIG. 30F. [Figure 31A] 1 illustrates a cross-sectional view of the system. [Figure 31B] FIG. 31B illustrates a perspective view of the liner removal component shown in FIG. 31A. [Figure 31C] FIG. 31B illustrates a perspective view of the liner removal component shown in FIG. 31A. [Figure 31D] 31B illustrates an enlarged view of the cam surface shown in FIG. 31A. [Figure 31E] FIG. 31B illustrates a perspective view of the liner removal component shown in FIG. 31A. [Figure 31F] FIG. 31B illustrates a perspective view of the liner removal component shown in FIG. 31A. [Figure 31G]FIG. 31B illustrates a side schematic view of a portion of the liner removal component shown in FIG. 31A. [Figure 31H] FIG. 31B illustrates a side schematic view of a portion of the liner removal component shown in FIG. 31A. [Figure 32A] 1 illustrates a perspective view of a liner removal component. [Figure 32B] 32B illustrates a cross-sectional view of the liner removal component shown in FIG. 32A. [Figure 32C] 32B illustrates a cross-sectional view of the liner removal component shown in FIG. 32A. [Figure 33A] 1 illustrates a cross-sectional view of the system. [Figure 33B] FIG. 33B illustrates a perspective view of the liner removal component shown in FIG. 33A. [Figure 33C] 33B illustrates a cross-sectional view of the liner removal component shown in FIG. 33A. [Figure 34A] 1 illustrates a cross-sectional view of the system. [Figure 34B] 34B illustrates a schematic perspective view of the system shown in FIG. 34A. [Figure 34C] 34B illustrates a bottom perspective view of the system shown in FIG. 34A. [Figure 34D] 34B illustrates a schematic perspective view of the system shown in FIG. 34A. [Figure 34E] 34B illustrates a perspective view of the system shown in FIG. 34A. [Figure 34F] 1 illustrates a cross-sectional perspective view of the system. [Figure 34G] 1 illustrates a perspective view of the system. [Figure 35] 1 illustrates a cross-sectional view of the system. [Figure 36A] 1 illustrates a cross-sectional view of the system. [Figure 36B] 36B illustrates a perspective view of the system shown in FIG. 36A. [Figure 37A] 1 illustrates a top view of a liner. [Figure 37B] 1 illustrates a top view of a liner. [Figure 37C] 1 illustrates a top view of a liner. [Figure 37D]1 illustrates a top view of a liner. [Figure 37E] 1 illustrates a top view of a liner. [Figure 37F] 1 illustrates a top view of a liner. [Figure 37G] 1 illustrates a top view of a liner. [Figure 37H] 1 illustrates a top view of a liner. [Figure 37I] 1 illustrates a top view of a liner. [Figure 37J] 1 illustrates a top view of a liner. [Figure 37K] 1 illustrates a perspective view of a liner. [Figure 37L] 37A illustrates a schematic perspective view of the liner shown in FIG. 37K separated. [Figure 37M] Each illustrates a top view of the liner. [Figure 37N] Each illustrates a top view of the liner. [Figure 37O] Each illustrates a top view of the liner. [Figure 37P] Each illustrates a top view of the liner. [Figure 38A] 1 illustrates an assembled perspective view of a liner removal component having a piercing layer. [Figure 38B] FIG. 38B illustrates a perspective view of the liner removal component shown in FIG. 38A. [Figure 38C] FIG. 38B illustrates a bottom cross-sectional perspective view of the liner removal component shown in FIG. 38A. [Figure 38D] FIG. 38B illustrates a side cross-sectional perspective view of the liner removal component shown in FIG. 38A. [Figure 38E] FIG. 38B illustrates a perspective view of the liner removal component shown in FIG. 38A. [Figure 39A] 1 illustrates a bottom perspective view of a patch. [Figure 39B] 39B illustrates a top perspective view of the patch shown in FIG. 39A. [Figure 39C] FIG. 39B illustrates a cross-sectional perspective view of the on-skin wearable medical device shown in FIG. 39A and including a patch positioned within the applicator housing. [Figure 39D] FIG. 39D illustrates a cross-sectional view of the on-skin wearable medical device shown in FIG. 39C and positioned within the applicator housing. [Figure 39E] FIG. 39D illustrates a bottom perspective view of the on-skin wearable medical device shown in FIG. 39C and positioned within the applicator housing. [Figure 40] 1 illustrates a cross-sectional perspective view of an on-skin wearable medical device. [Figure 41A] 41 illustrates a distal view of the on-skin wearable medical device shown in FIG. 40. [Figure 41B] 41B illustrates a schematic cross-sectional view of the on-skin wearable medical device shown in FIG. 41A along line BB of FIG. 41. [Figure 42] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 43A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 43B] 43B illustrates a schematic side view of the on-skin wearable medical device shown in FIG. 43A, with the spiral body moved from the position shown in FIG. 43A. [Figure 43C] 43B illustrates a side schematic view of the on-skin wearable medical device shown in FIG. 43A applied to the skin. [Figure 44] 1 illustrates a distal perspective view of an on-skin wearable medical device. [Figure 45A] 1 illustrates a close-up perspective view of a cap. [Figure 45B] 45B illustrates a cross-sectional perspective view of an applicator housing including the cap shown in FIG. 45A. [Figure 45C] 45B illustrates a cross-sectional view of an applicator housing including the cap shown in FIG. 45A. [Figure 46] 1 illustrates a distal perspective view of an on-skin wearable medical device. [Figure 47A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 47B] 47B illustrates an assembly diagram of the patch shown in FIG. 47A. [Figure 47C]47B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 47A taken along line CC shown in FIG. 47A. [Figure 47D] 47B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 47A taken along line DD shown in FIG. 47A. [Figure 47E] 47B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 47A taken along line EE shown in FIG. 47A. [Figure 47F] 47B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 47A taken along line FF shown in FIG. 47A. [Figure 48A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 48B] 48B illustrates an assembly diagram of the patch shown in FIG. 48A. [Figure 48C] 48B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 48A taken along line CC shown in FIG. 48A. [Figure 48D] 48B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 48A taken along line DD shown in FIG. 48A. [Figure 49A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 49B] 49B illustrates an assembly diagram of the patch shown in FIG. 49A. [Figure 50] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 51] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 52] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 53] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 54A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 54B]54B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 54A taken along line BB shown in FIG. 54A. [Figure 55A] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 55B] 55B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 55A taken along line BB shown in FIG. 55A. [Figure 55C] 55B illustrates a schematic cross-sectional view of a portion of the on-skin wearable medical device shown in FIG. 55A taken along line CC shown in FIG. 55A. [Figure 56] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 57] 1 illustrates a cross-sectional perspective view of an on-skin wearable medical device. [Figure 58] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 59] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 60] 1 illustrates a cross-sectional side view of an on-skin wearable medical device. [Figure 61] 1 illustrates an assembled cross-section of a patch. [Figure 62] 1 illustrates an assembled cross-section of a patch. [Figure 63] 63 illustrates a proximal view of the patch shown in FIG. 62. [Figure 64] 1 illustrates a proximal view of an on-skin wearable medical device. [Figure 65] 65 illustrates a distal view of the on-skin wearable medical device shown in FIG. 64. [Figure 66] 1 illustrates a distal view of an on-skin wearable medical device. [Figure 67] 10 illustrates a distal perspective view of a liner removal component. [Figure 68] 68 illustrates a schematic cross-sectional view of the liner removal component shown in FIG. 67. [Figure 69] 1 illustrates a schematic cross-sectional view of a liner removal component. [Figure 70] 1 illustrates a schematic cross-sectional view of a liner removal component. [Figure 71] 1 illustrates a schematic cross-sectional view of a liner removal component. [Figure 72] 1 illustrates a schematic cross-sectional view of a liner removal component. [Figure 73] 1 illustrates a schematic cross-sectional view of a liner removal component. DETAILED DESCRIPTION OF THE INVENTION

[0034] The following description and examples detail some exemplary embodiments of the present disclosure. Those skilled in the art will recognize that there are many variations and modifications of the present disclosure that are encompassed by the scope of the present disclosure. Therefore, the description of a particular exemplary embodiment should not be considered as limiting the scope of the present disclosure.

[0035] 1 is a diagram depicting an exemplary medical device system according to embodiments herein. The medical device system in embodiments may comprise a continuous analyte monitoring system 100. The continuous analyte monitoring system 100 may include an analyte sensor system 102 comprising an on-skin sensor assembly 160 configured to be fastened to the skin of a recipient via a base (not shown).

[0036] In embodiments, other forms of medical device systems may be utilized, including other forms of monitoring systems, drug delivery systems, or other treatment systems. In embodiments, on-skin wearable medical devices may be utilized, which may include on-skin sensor assemblies or drug delivery medical devices, among other forms of on-skin wearable medical devices.

[0037] As shown in FIG. 1 , the analyte sensor system 102 can be operatively connected to a recipient and multiple display devices 110-114 in accordance with certain aspects of the present disclosure. Exemplary display devices 110-114 can include computers such as smartphones, smartwatches, tablet computers, laptop computers, and desktop computers. In some embodiments, the display devices 110-114 can be Apple Watches, iPhones, and iPads manufactured by Apple Inc., or iOS, Windows, or Android operating system devices. Note that the display device 114 can alternatively or additionally be a display device and a drug delivery device capable of cooperatively operating with the analyte sensor system 102 to deliver a drug to the recipient. The analyte sensor system 102 can include a sensor electronics module 140 and a continuous analyte sensor 138 associated with the sensor electronics module 140. The sensor electronics module 140 can communicate directly and wirelessly with one or more of the multiple display devices 110-114 via wireless communication signals. As discussed in more detail below, the display devices 110-114 may also communicate among one another and / or through one another to the analyte sensor system 102. For ease of reference, wireless communication signals from the analyte sensor system 102 to the display devices 110-114 may be referred to as “uplink” signals 128. For example, wireless communication signals from the display devices 110-114 to the analyte sensor system 102 may be referred to as “downlink” signals 130. Wireless communication signals between two or more of the display devices 110-114 may be referred to as “crosslink” signals 132. Additionally, wireless communication signals may include data transmitted by one or more of the display devices 110-113 to one or more remote servers 190, or network entities such as cloud-based servers or databases, via “long-range” uplink signals 136 (e.g., cellular signals), and may receive long-range downlink signals 142 transmitted by the remote servers 190.

[0038] 1 , one of the multiple display devices may be a custom display device 111 specifically designed to display a particular type of displayable sensor information (e.g., in some embodiments, numbers and arrows) associated with the analyte value received from the sensor electronics module 140. In some embodiments, one of the multiple display devices may be a handheld device 112, such as a mobile phone, palmtop computer, or the like based on the Android operating system, iOS operating system, or other operating system, which may have a relatively large display and be configured to display a graphical representation of continuous sensor data (e.g., including current and historical data). Other display devices may include a tablet 113, a smartwatch 110, a medication delivery device 114, a blood glucose meter, and / or other handheld devices such as a desktop or laptop computer.

[0039] In the case of the display device 114, which may be a drug delivery device in addition to or instead of a display device, it should be understood that the alert and / or sensor information provided by the continuous analyte sensor 138 to the sensor electronics module 140 may be used to initiate and / or adjust the delivery of the drug to the recipient.

[0040] During use, the sensing portion of the sensor 138 may be disposed under the recipient's skin, and the contact portion of the sensor 138 may be electrically connected to the sensor electronics module 140. The electronics module 140 may be engaged with a housing (e.g., a base) that is attached to a patch that can engage the recipient's skin. The patch may be an adhesive patch in embodiments. In some embodiments, the electronics module 140 is integrally formed with the housing. Furthermore, the electronics module 140 may be disposable or may be directly coupled to the patch.

[0041] The continuous analyte sensor system 100 can include any sensor configuration that provides an output signal indicative of an analyte concentration. The output signal, which includes sensor data (e.g., a raw data stream, filtered data, smoothed data, and / or otherwise transformed sensor data), is transmitted to a receiver.

[0042] In some embodiments, the analyte sensor system 102 includes a transcutaneous glucose sensor such as that described in U.S. Patent Application Publication No. 2011 / 0027127, the entire contents of which are incorporated herein by reference. In some embodiments, the sensor system 102 includes a continuous glucose sensor and comprises a transcutaneous sensor (e.g., as described in U.S. Patent No. 6,565,509, as described in U.S. Patent No. 6,579,690, and / or as described in U.S. Patent No. 6,484,046). The contents of U.S. Patent Nos. 6,565,509, 6,579,690, and 6,484,046 are incorporated herein by reference in their entireties.

[0043] Various signal processing techniques and glucose monitoring system embodiments suitable for use with the embodiments described herein are described in U.S. Patent Application Publication Nos. 2005 / 0203360 and 2009-0192745-(A1), the contents of which are incorporated herein by reference in their entireties. The sensor can extend through a housing, which can maintain the sensor 138 on, in, or under the skin and / or can provide an electrical connection of the sensor 138 to the sensor electronics in the sensor electronics module 140.

[0044] In some embodiments, descriptions of the base, housing, garment, and / or transmitter of the on-skin sensor assembly 160 may be interchangeable. In other embodiments, the base and housing of the on-skin sensor assembly 160 may differ from the sensor electronics module 140 in the sense that they may be separate components from the transmitter or receiver, for example.

[0045] In some embodiments, the sensor 138 is in the form of a wire. The distal end of the wire can be formed, for example, to have a conical shape (to facilitate insertion of the wire into the recipient's tissue). The sensor 138 can include an elongated analyte sensor and can include an elongated conductive body, such as an elongated conductive core (e.g., a metal wire) or an elongated conductive core coated with one, two, three, four, five, or more layers of material, each of which may or may not be conductive. The elongated analyte sensor can be long and thin, yet flexible and strong. For example, in some examples, the smallest dimension of the elongated conductive body is less than 0.1 inches, less than 0.075 inches, less than 0.05 inches, less than 0.025 inches, less than 0.01 inches, less than 0.004 inches, less than 0.002 inches, less than 0.001 inches, and / or less than 0.0005 inches.

[0046] The sensor 138 may have a circular cross-section. In some embodiments, the cross-section of the elongated conductive body may be oval, rectangular, triangular, polyhedral, star-shaped, C-shaped, T-shaped, X-shaped, Y-shaped, irregular, etc. In some embodiments, a conductive wire electrode is used as the core. In other embodiments, the sensor 138 may be disposed on a substantially flat substrate. One or two additional conductive layers may be added to such an electrode (e.g., with an intervening insulating layer providing electrical isolation). The conductive layer may be made of any suitable material. In certain embodiments, it may be desirable to use a conductive layer comprising conductive particles (i.e., particles of a conductive material) in a polymer or other binder.

[0047] In some embodiments, the materials used to form the elongated conductive body (e.g., stainless steel, titanium, tantalum, platinum, platinum-iridium, iridium, certain polymers, and / or the like) can be strong and stiff, and therefore resistant to breakage. For example, in some embodiments, the ultimate tensile strength of the elongated conductive body is greater than 80 kPsi and less than 140 kPsi, and / or the Young's modulus of the elongated conductive body is greater than 160 GPa and less than 220 GPa. The yield strength of the elongated conductive body can be greater than 58 kPsi and less than 2200 kPsi.

[0048] Electronics module 140 may be releasably or permanently coupled to sensor 138. Electronics module 140 may include electronic circuitry related to measuring and processing continuous analyte sensor data. Electronics module 140 may be configured to execute algorithms related to processing and calibrating sensor data. For example, electronics module 140 may provide various aspects of sensor electronics module functionality such as those described in U.S. Patent Application Publication Nos. 2009 / 0240120 and 2012 / 0078071, the entire contents of which are incorporated herein by reference. Electronics module 140 may include hardware, firmware, and / or software that enables measurement of analyte levels via a glucose sensor, such as sensor 138.

[0049] For example, electronics module 140 may include a potentiostat, a power supply for providing power to sensor 138, signal processing components, data storage components, and a communications module (e.g., a telemetry module) for one-way or two-way data communication between electronics module 140 and one or more receivers, repeaters, and / or display devices, such as devices 110-114. The electronics components may be affixed to a printed circuit board (PCB) or the like and may take a variety of forms. The electronics components may take the form of integrated circuits (ICs), such as application-specific integrated circuits (ASICs), microcontrollers, and / or processors. Electronics module 140 may include sensor electronics configured to process sensor information, such as by storing data, analyzing data streams, calibrating analyte sensor data, estimating analyte values, comparing estimated analyte values ​​with corresponding measured analyte values ​​over time, and analyzing fluctuations in estimated analyte values. Examples of systems and methods for processing sensor analyte data are described in more detail in U.S. Pat. No. 7,310,544, U.S. Pat. No. 6,931,327, U.S. Patent Application Publication No. 2005 / 0043598, U.S. Patent Application Publication No. 2007 / 0032706, U.S. Patent Application Publication No. 2007 / 0016381, U.S. Patent Application Publication No. 2008 / 0033254, U.S. Patent Application Publication No. 2005 / 0203360, U.S. Patent Application Publication No. 2005 / 0154271, U.S. Patent Application Publication No. 2005 / 0192557, U.S. Patent Application Publication No. 2006 / 0222566, U.S. Patent Application Publication No. 2007 / 0203966, and U.S. Patent Application Publication No. 2007 / 0208245, the contents of which are incorporated herein by reference in their entireties. Electronics module 140 may communicate with devices 110-114, and / or any number of additional devices, via any suitable communication protocol.Exemplary communication methods or protocols include radio frequency; Bluetooth; Universal Serial Bus; wireless local area network (WLAN) communication standards including IEEE 802.11, 802.15, 802.20, 802.22 and other 802 communication protocols; ZigBee; wireless (e.g., cellular) communication; paging network communication; magnetic induction; satellite data communication; proprietary communication protocols, open source communication protocols, and / or any suitable wireless communication method.

[0050] Additional sensor information is provided in U.S. Patent Nos. 7,497,827 and 8,828,201, the entire contents of which are incorporated herein by reference.

[0051] Any sensor shown or described herein may be an analyte sensor, a glucose sensor, and / or any other suitable sensor. The sensor described in the context of any embodiment may be any sensor described herein or incorporated by reference. The sensors shown or described herein may be configured to sense, measure, detect, and / or interact with any analyte.

[0052] The term "analyte" is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not limited to any special or customized meaning), and refers to, but is not limited to, a substance or chemical constituent in a biological fluid (e.g., blood, interstitial fluid, cerebrospinal fluid, lymphatic fluid, urine, sweat, saliva, etc.) that can be analyzed. Analytes can include naturally occurring substances, man-made substances, metabolites, or reaction products.

[0053] In some embodiments, the analyte measured by the sensing region, device, and method is glucose. However, other analytes may be measured, including, but not limited to, ketone bodies; acetyl-CoA; acarboxyprothrombin; acylcarnitines; adenine phosphoribosyltransferase; adenosine deaminase; albumin; α-fetoprotein; amino acid profile (arginine (Krebs cycle), histidine / urocanic acid, homocysteine, phenylalanine / tyrosine, tryptophan); andrenostenedione; antipyrine; arabinitol enantiomers; arginase; benzoylecgonine (cocaine); biotinidase; biopterin; c-reactive protein; carnitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; cholinesterase; cortisol; testosterone; choline; creatine kinase; creatine kinase MM isoenzyme; cyclosporin A; d-penicillamine; deethoxycholic acid; Chloroquine; Dehydroepiandrosterone sulfate; DNA (acetylation polymorphism, alcohol dehydrogenase, α1-antitrypsin, cystic fibrosis, Duchenne / Becker muscular dystrophy, glucose-6-phosphate dehydrogenase, hemoglobin A, hemoglobin S, hemoglobin C, hemoglobin D, hemoglobin E, hemoglobin F, D-Punjab, β-thalassemia, hepatitis B virus, HCMV, HIV-1, HTLV- 1, Leber's hereditary optic neuropathy, MCAD, RNA, PKU, Plasmodium vivax, sex differentiation, 21-deoxycortisol); desbutylhalofantrine; dihydropteridine reductase; diphtheria / tetanus antitoxin; erythrocyte arginase; erythrocyte protoporphyrin; esterase D; fatty acids / acylglycines; triglycerides; glycerol; free beta-human chorionic gonadotropin; free erythrocyte porphyrin; free thyroxine (FT4); free triiodothyronine (FT3); fumarylacetoacetase; galactose / gal-1-phosphate; galactose-1-phosphate uridyltransferase; gentamicin; glucose-6-phosphate dehydrogenase; glutathione;Glutathione peroxidase; glycocholate; glycosylated hemoglobin; halofantrine; hemoglobin variants; hexosaminidase A; human erythrocyte carbonic anhydrase I; 17-α-hydroxyprogesterone; hypoxanthine phosphoribosyltransferase; immunoreactive trypsin; lactate; lead; lipoproteins ((a), B / A-1, β); lysozyme; mefloquine; netilmicin; phenobarbitone; phenytoin; phytanic acid / pristanic acid; progesterone; prolactin; prolidase; purine nucleoside phosphorylase; quinine; reverse triiodothyronine tri-iodothyronine, rT3); selenium; serum pancreatic lipase; sisomicin; somatomedin C; specific antibodies (adenovirus, antinuclear antibody, anti-zeta antibody, arbovirus, pseudorabies virus, dengue virus, guinea worm, Echinococcus granulosus, Entamoeba histolytica, enterovirus, giardiasis, Helicobacter pylori, hepatitis B virus, herpes virus, HIV-1, IgE (atopic disease), influenza virus, Leishmania donovani, Leptospirosis, measles / mumps / rubella, Mycobacterium leprae, Mycoplasma pneumoniae, myoglobin, Onchocerciasis volvulus, parainfluenza virus, malaria parasite, poly Oviruses, Pseudomonas aeruginosa, respiratory syncytial virus, Rickettsia (tsutsugumushi disease), Schistosoma mansoni, Toxoplasma gondii, Treponema pallidum, Trypanosoma cruzi / rangeli, Vesicular stomatitis virus, Wuchereria bancrofti, Yellow fever virus); Specific antigens (Hepatitis B virus, HIV-1); Acetone (e.g., succinylacetone); Acetoacetic acid; Sulfadoxine; Theophylline; Thyrotropin (TSH); Thyroxine (T4); Thyroxine-binding globulin; Trace elements; Transferrin; UDP-galactose-4-epimerase; Urea; Uroporphyrinogen I synthase; Vitamin A; Leukocytes;and zinc protoporphyrin, and the like, are also contemplated. Salts, sugars, proteins, fats, vitamins, and hormones naturally present in blood or interstitial fluid can also constitute analytes in certain embodiments. Analytes can be naturally occurring in biological fluids or can be endogenous, e.g., metabolites, hormones, antigens, antibodies, and the like. Alternatively, analytes can be introduced into the body or can be exogenous, e.g., contrast agents for imaging, radioisotopes, chemical agents, fluorocarbon-based synthetic blood, or drugs or pharmaceutical compositions, including, but not limited to, insulin; glucagon; ethanol; cannabis (marijuana, tetrahydrocannabinol, hashish); inhalants (nitrous oxide, amyl nitrite, butyl nitrite, chlorohydrocarbons, hydrocarbons); cocaine (crack cocaine); stimulants (amphetamine, methamphetamine, Ritalin, Silurt, Preludine, Didrex, Prestate, Boranil, Sandrek, etc.). antidepressants (barbiturates, tranquilizers such as methaqualone, Valium, Librium, Miltaunt, Serax, Equuanil, and Tranxine); hallucinogens (phencyclidine, lysergic acid, mescaline, peyote, and psilocybin); narcotics (heroin, codeine, morphine, opium, meperidine, Percocet, Percodan, Tasionex, fentanyl, Darvon, Talwin, and Lomotil); synthetic narcotics (fentanyl, meperidine, amphetamine, methamphetamine, and phencyclidine analogs, e.g., ecstasy); anabolic steroids;Analytes of interest include, but are not limited to, ascorbic acid, uric acid, dopamine, noradrenaline, 3-methoxytyramine (3MT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxytryptamine (5HT), 5-hydroxyindoleacetic acid (FHIAA), and citric acid cycle intermediates, as well as other chemicals produced in the body, can also be analyzed.

[0054] Any of the features described at least in connection with Figure 1 may be applicable to all aspects and embodiments identified herein. Furthermore, any of the features of an embodiment may be independently combinable in any manner, partially or wholly, with other embodiments described herein, e.g., one, two, or more embodiments may be combinable in whole or in part. Furthermore, any of the features of an embodiment may be optional for other aspects or embodiments. Any aspect or embodiment of a method may be implemented by a system or device of another aspect or embodiment, and any aspect or embodiment of a system may be configured to implement a method of another aspect or embodiment.

[0055] 2A illustrates a perspective view of an exemplary on-skin wearable medical device in the form of an on-skin sensor assembly 200 configured to be placed on the skin. The on-skin sensor assembly 200 may include a housing or base 202. The housing or base 202 may be configured to be worn on the skin of a recipient and may include a distal surface for facing the skin and a proximal surface 203 facing opposite the distal surface. The housing or base 202 may include an opening 205 for allowing an insertion element to be retracted proximally from the skin therethrough. A patch 204, such as an adhesive patch, may couple the base 202 to the recipient's skin 206. The patch 204 may be positioned on the distal surface of the housing or base 202. In some examples, the adhesive patch 204 may include an engagement surface that engages the skin and includes an adhesive suitable for skin adhesion, such as a pressure-sensitive adhesive (e.g., acrylic, rubber-based, or other suitable type) bonded to a carrier substrate (e.g., spunlace polyester, polyurethane film, or other suitable type) for skin attachment (however, any suitable type of adhesive is contemplated). The on-skin sensor assembly 200 may include an electronics unit 208 (e.g., a transmitter) that may further include an analyte sensor, such as a transcutaneous analyte sensor (e.g., glucose sensor) 212 and a glucose sensor module 210 coupled to the base 202.

[0056] The applicator system can engage the adhesive patch 204 to the skin 206. The glucose sensor module 210 may be secured to the base 202 (e.g., via retaining elements such as snap-fit ​​and / or interference features, adhesive, welding, etc.) to ensure that the analyte sensor 212 (e.g., glucose sensor) is coupled to the base 202. In an alternative embodiment, the sensor module 210 and the base 202 are pre-assembled or manufactured as a single component.

[0057] After the on-skin sensor assembly 200 is placed on the user's skin, the user (or applicator) can couple the electronics unit 208 (e.g., a transmitter) to the on-skin sensor assembly 200 via retention elements, such as snap-fit ​​features and / or interferometric features. The electronics unit 208 can measure and / or analyze glucose indicators sensed by the transcutaneous analyte sensor (e.g., glucose sensor) 212. The electronics unit 208 can transmit information (e.g., measurements, analyte data, glucose data) to remotely located devices (e.g., 110-114 shown in FIG. 1 ).

[0058] The on-skin sensor assembly 200 may be attached to a recipient using an applicator adapted to provide convenient and safe application. Such an applicator may also be used to attach the electronics unit 208 to the base 202, to insert the sensor 212 through the recipient's skin, and / or to connect the sensor 212 to the electronics unit 208. Once the electronics unit 208 is engaged with the base and the sensor 212 is inserted into the skin (and connected to the electronics unit 208), the sensor assembly can be detached from the applicator.

[0059] 2B illustrates a perspective view of electronics unit 208 coupled to base 202 via retention elements, such as snap-fit ​​and / or interference features. In some embodiments, electronics unit 208 and base 202 are coupled by adhesive, welding, or other joining techniques. Patch 204 on the distal surface of base 202 is configured to couple sensor assembly 200 to the skin.

[0060] 2C illustrates a perspective view of the on-skin sensor assembly 200. The on-skin sensor assembly 200 may be disposable or reusable. FIG. 2C further illustrates an electronics unit 208 coupled to the base 202 and a patch 204 configured to be attached to the on-skin sensor assembly 200, which, when combined, can be held within an applicator.

[0061] FIG. 3 illustrates an embodiment of an on-skin wearable medical device in the form of an on-skin sensor assembly 300 with an electronics unit 302 configured to insert into a cavity 304 of a base or housing 306. The base or housing 306 may be configured to be worn on a recipient's skin and may include a distal surface for facing the skin and a proximal surface 305 facing opposite the distal surface. The electronics unit 302 may include one or more tabs 308 that couple to a portion of the housing 306 and allow the electronics unit 302 to be held by the housing 306. The housing 306 may include an opening 310 for retracting an insertion element therethrough proximally from the skin. The opening 310 may allow an insertion element (such as a needle) to pass through to place the transcutaneous analyte sensor 312 on the skin. The patch 314 may further include an opening 316 that can allow the sensor 312 and insertion element to pass through. The electronics unit 302 may be coupled to the housing 306 either before or after placement of the sensor 312 on the recipient's skin.

[0062] 4 illustrates one embodiment of an on-skin wearable medical device in the form of an on-skin sensor assembly 400, in which an electronics unit is integrated with a housing 402. The housing 402 may be configured to be worn on the skin of a recipient and may include a distal surface for facing the skin and a proximal surface 403 facing opposite the distal surface. The on-skin sensor assembly 400 is shown on the skin 404, with a patch 406 engaged to the skin 404.

[0063] 2A-4 may each include an engagement surface for engaging the skin. The engagement surface may, in embodiments, be located on the patch, for example, on the distal surface of the patch, or may have another location in embodiments. The engagement surface may, in embodiments, comprise an adhesive surface configured to adhere to the skin. The adhesive may be configured to adhere to the skin. Additional adhesive information is described in U.S. Patent No. 11,219,413, filed August 25, 2015, the entire contents of which are incorporated herein by reference. In embodiments, the engagement surface may be covered with a liner prior to placement on the recipient's skin.

[0064] 5 illustrates a system for placing an on-skin wearable medical device on the skin. The system may include an applicator system in embodiments. The system may include an applicator for an on-skin sensor assembly of an analyte sensor system, according to some embodiments. In embodiments, other forms of the system may be utilized.

[0065] The applicator 500 may include an applicator housing 501, which may include an outer housing 504 and an inner housing 506, as well as other forms of housing in embodiments. The applicator housing 501, in embodiments, may be configured to hold the on-skin wearable medical device. The applicator 500 may include a placement mechanism, which may be configured to place the on-skin wearable medical device on the skin. The placement mechanism may, for example, in embodiments, include one or more holding elements for holding the on-skin wearable medical device and releasing the on-skin wearable medical device from the applicator housing 501 and relative to the skin. The placement mechanism may include an insertion assembly for inserting at least a portion of the on-skin wearable medical device into the skin. The insertion assembly may drive the insertion element and a portion of the on-skin wearable medical device, such as a sensor, into the recipient's skin. The placement mechanism may include a retraction assembly for retracting a portion of the on-skin wearable medical device, such as the insertion element, from the skin.

[0066] In embodiments, the applicator 500 may include an actuation element 502 disposed on a side of the applicator 500, for example, on a side of the outer housing 504 of the applicator 500. In some embodiments, the actuation element 502 may be a button, a switch, a toggle, a slide, a trigger, a knob, a rotating member, a portion of the applicator 500 that deforms and / or bends, or any other suitable mechanism for actuating the insertion and / or retraction assembly of the applicator 500. In some embodiments, the actuation element 502 may be disposed anywhere, for example, on the top, upper side, lower side, or any other location of the applicator 500. The applicator 500 may be large enough for a recipient to grasp in their hand and press or otherwise actuate the actuation element 502 with, for example, their thumb, or index and / or middle finger.

[0067] The applicator 500 may be configured with one or more safety features such that the applicator 500 is prevented from activating until the safety feature is deactivated. In one example, the one or more safety features prevent the applicator 500 from being actuated unless the applicator 500 is pressed against the recipient's skin with sufficient force. Furthermore, as described in more detail in connection with one or more of FIGS. 6-20B below, the applicator 500 may be further configured such that one or more components within the applicator 500 retract based, at least in part, on the one or more components pressing against the recipient's skin with a force above a predetermined threshold, rather than based on the one or more components moving linearly beyond a predetermined static distal position. In other words, the applicator 500 is capable of implementing force-based retraction triggering rather than being limited to displacement-based retraction triggering.

[0068] 6 illustrates an exploded perspective view of the applicator 500 of FIG. 5, according to some embodiments. The applicator 500 may include an outer applicator housing 504 with an actuation element 502. The outer applicator housing 504, in embodiments, may be configured to be grasped by a user. The outer applicator housing 504 may be configured to translate distally by a recipient applying a force to the applicator 500 (specifically the inner housing 506), thereby aligning the actuation element 502 in a position that allows the applicator 500 to fire. Further description of the alignment process is provided below.

[0069] The applicator 500 further comprises an inner housing 506 configured to house at least one or more mechanisms utilized to apply the on-skin sensor assembly 508 to the skin of a recipient. A distal surface 510 of the bottom opening of the inner housing 506 may define a bottom surface of the applicator 500. In some embodiments, when the applicator 500 is pressed against the skin of a recipient, the skin may deform substantially convexly at the distal surface 510 such that at least a portion of the surface of the skin disposed at the bottom opening of the applicator inner housing 506 extends proximally beyond a plane defined by the distal surface 510 and into the bottom opening of the inner housing 506.

[0070] 7, the housing 501, particularly the inner housing 506, can include an internal cavity 503 for holding an on-skin wearable medical device. The internal cavity 503 can have a distal end portion 505 at an opening for allowing the on-skin wearable medical device to be placed therethrough. A proximal end portion 507 of the internal cavity 503 can contain the on-skin wearable medical device coupled to a needle carrier assembly 516.

[0071] 6 , in some embodiments, a first barrier layer 512 may be disposed over one or more openings in inner housing 506, such as opening 514 through which at least a portion of actuating element 502 may be configured to extend during actuation of applicator 500. In such embodiments, the portion of actuating element 502 may be configured to puncture or deform first barrier layer 512 upon actuation of applicator 500. First barrier layer 512 may comprise a gas-permeable material, such as Tyvek, or a gas-impermeable material, such as a metal foil, a polymer film, an elastomer, or any other suitable material.

[0072] The applicator 500 may further comprise a needle carrier assembly 516 including a needle hub 518 configured to couple an insertion element 520 to the needle carrier assembly 516. In some other embodiments, the insertion element 520 may be directly coupled to the needle carrier assembly 516. The insertion element 520 is configured to insert a sensor of the on-skin sensor assembly 508 into the skin of a recipient. In some embodiments, the insertion element comprises a needle, such as an open-side needle, a needle with a deflectable tip, a curved needle, a polymer-coated needle, a hypodermic needle, or any other suitable type of needle or structure. In still other embodiments, the insertion element 520 may be integrally formed with the sensor and may be rigid enough to be inserted partially into the skin of a recipient with minimal or no structural support.

[0073] The applicator 500 may further include a holder 522 releasably coupled to the needle carrier assembly 516, the holder 522 configured to guide the needle carrier assembly 516 and the on-skin sensor assembly 508 while coupled to the needle carrier assembly 516, for example, during translation from at least a proximal position to a distal insertion position. As described in more detail below, the on-skin sensor assembly 508 may be removed or released from the holder 522 and / or the needle carrier assembly 516 once the on-skin sensor assembly 508 is disposed on the skin of the recipient. For example, one or more retaining elements may release the on-skin wearable medical device from the applicator housing 501.

[0074] The applicator 500 may further comprise an insertion assembly configured to translate the insertion element 520, the needle hub 518, the needle carrier assembly 516, and the on-skin sensor assembly 508 distally from a proximal position to a distal insertion position. Such an insertion assembly may include at least one spring for inserting at least a portion of the on-skin wearable medical device into the skin. The insertion assembly may include a first spring 524. The first spring 524 may be a compression spring or any suitable type of spring and may have a first end in contact with or coupled to the inner applicator housing 506 and a second end in contact with or coupled to the holder 522. The first spring 524 is configured to translate the holder 522, the needle carrier assembly 516, the needle hub 518, the insertion element 520, and the on-skin sensor assembly 508 distally to the distal insertion position upon actuation of the insertion assembly. In a substantially distal insertion position, the needle carrier assembly 516 may be separated from the holder 522 and the on-skin sensor assembly 508 .

[0075] The applicator 500 may further include a retraction assembly for retracting the insertion element (e.g., needle) from the skin. The retraction assembly may be configured to translate the needle carrier assembly 516, the needle hub 518, and the insertion element 520 in a proximal direction from a distal insertion position to a proximal retracted position. In some embodiments, the initial proximal position may be the same as the proximal retracted position. In other embodiments, the initial proximal position may be different from the proximal retracted position. Such a retraction assembly may include at least one spring. The retraction assembly may include a second spring 526. The second spring 526 may be a compression spring or any suitable type of spring and may have a first end that contacts or couples with the holder 522, at least until retracted, and a second end that contacts or couples with at least one spring retaining element (e.g., 528a, 528b in FIGS. 10-14). The second spring 526 is configured to translate the needle carrier assembly 516, the needle hub 518, and the insertion element 520 proximally from a distal insertion position to a proximal retracted position in response to the on-skin sensor assembly 508 contacting the recipient's skin and / or the first end of the second spring 526 reaching a limit of travel with a force above a predetermined threshold sufficient to overcome at least one spring retaining element (e.g., 528a, 528b in FIGS. 10-14 ). In some embodiments, a stop feature (not shown) may be disposed at a bottom of the applicator 500, for example, on a distal portion of the inner housing 506. Such a stop feature may be configured to contact one or more of the on-skin sensor assembly 508, the needle carrier assembly 516, or the holder 522 at the distal insertion position.

[0076] In some embodiments, a second barrier layer 530 may be disposed over the bottom opening of the inner housing 506. The second barrier layer 530 may comprise a gas-permeable material, such as Tyvek, or a gas-impermeable material, such as a metal foil or film. In some embodiments, the second barrier layer 530 may be removed by a recipient prior to use of the applicator 500. In embodiments comprising one or both of the first barrier layer 512 and the second barrier layer 530, such layers may provide a sterile environment between the applicator 500 and the external environment and / or may allow for the ingress and egress of gases, such as during sterilization.

[0077] A brief description of some aspects of the operation of applicator 500 follows below with reference to Figures 7-9, which illustrate several cross-sectional views of applicator 500 of Figures 5 and 6 in operation, according to some embodiments. Figures 7-9 may correspond, for example, to applicator 500 cut along section line A-A' shown in Figure 5.

[0078] 7 illustrates the pre-activation state of applicator 500. Holder 522 includes an insertion assembly retaining element 532 configured to contact inner housing 506 to secure holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 in the pre-activation state.

[0079] The needle carrier assembly 516 includes a plurality of wearable retention and / or alignment elements 534a, 534b that extend through the holder 522 and are configured to releasably couple the on-skin sensor assembly 508 to the holder 522 and / or the needle carrier assembly 516. The wearable retention elements 534a, 534b may include, for example, arms, flexible elements, tabs, detents, snaps, or any other feature capable of retention functionality. In some embodiments, the wearable retention elements 534a, 534b may extend around, rather than through, the holder 522. While two wearable retention elements are shown, any number of wearable retention elements is contemplated. In some embodiments, the wearable retention elements 534a, 534b may include a snap fit, a friction fit, an interference feature, an elastomeric grip, and / or an adhesive configured to couple the on-skin sensor assembly 508 with the needle carrier assembly 516 and / or the holder 522.

[0080] Inner housing 506 may include a spring 536 configured to contact outer housing 504 and maintain a predetermined spacing between outer housing 504 and inner housing 506 in the pre-actuated orientation of FIG. 7. Spring 536 may be a compression spring, a leaf spring, a flex arm spring, a piece of foam or rubber, or the like. In some other embodiments, outer housing 504 may include spring 536, and spring 536 may be configured to contact inner housing 506 in a manner opposite to that shown in FIG. 7.

[0081] Actuation of the applicator 500 may include the recipient pressing the applicator 500 against their skin with sufficient force to translate the outer housing 504 toward and distally relative to the inner housing 506, as indicated by arrow 538, until the actuation element 502 is aligned with the opening 514 of the inner housing 506 and the insertion assembly retaining element 532 of the holder 522. The insertion assembly retaining element 532 may comprise, for example, arms, deflection elements, tabs, detents, snaps, or any other feature capable of retaining functionality. Once such alignment is achieved, the recipient may initiate (e.g., push) the actuation element 502, as indicated by arrow 540, thereby sufficiently deflecting the insertion assembly retaining element 532 to release the holder 522 from the inner housing 506. In some other embodiments, applicator 500 may be configured such that actuation element 502 may be actuated first, but actual insertion is not triggered until outer housing 504 has been sufficiently translated distally toward and relative to inner housing 506. In still other embodiments, actuation element 502 may be biased toward the center of applicator 500 such that actuation element 502 does not need to be explicitly actuated by the recipient, but instead, actuation element 502 may be configured to automatically begin insertion once outer housing 504 has been sufficiently translated distally toward and relative to inner housing 506.

[0082] Such a configuration offers several advantages. First, the linear movement of outer housing 504 relative to inner housing 506 prior to actuation provides a measure of drop protection to prevent premature firing if applicator 500 is accidentally dropped. Second, spring 536 provides a biasing force that the recipient must actively overcome by pressing applicator 500 into the recipient's skin prior to firing, thereby reducing the likelihood of actuating applicator 500 before it is properly positioned. Furthermore, the recipient may decide not to fire applicator 500 and cease pressing applicator 500 against their skin, in which case spring 536 will bias against outer housing 504, allowing outer housing 504 to return to its initial state.

[0083] The holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, on-skin sensor assembly 508, first spring 524, and second spring 526 are all shown in a pre-actuated position in FIG.

[0084] Figure 8 illustrates the applicator 500 during insertion of the on-skin sensor assembly 508, but before retraction of the needle carrier assembly 516. The first spring 524 drives the holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 distally toward the distal insertion position. Figure 8 illustrates a position where the on-skin sensor assembly 508 is in contact with the recipient's skin, but the holder 522 has not yet been fully driven by the first spring 524 into contact with the on-skin sensor assembly 508 or the recipient's skin.

[0085] In some embodiments, the mass of each of the holder 522, needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 may be specifically designed to reduce or substantially eliminate the tendency of the needle carrier assembly 516, needle hub 518, insertion element 520, and on-skin sensor assembly 508 to become dislodged from the holder 522 due to inertial forces while being driven distally during insertion. In some embodiments, the force exerted by the first spring 524 may be selected to be sufficient for proper operation of the applicator 500, but not so great as to further exacerbate such inertially triggered separation described above. In some embodiments, a spring (not shown) may be configured to exert a force against a portion of the needle carrier assembly 516, e.g., in a distal direction, sufficient to prevent inertially triggered separation of the needle carrier assembly 516 from the holder 522 during insertion.

[0086] FIG. 9 illustrates the applicator 500 in operation when the needle carrier assembly 516, needle hub 518, and insertion element 520 are retracted proximally by the second spring 526. In FIG. 9, the first spring 524 fully drives the on-skin sensor assembly 508 against the recipient's skin. In this position, the second spring 526 is released from the spring retaining element (e.g., 528a, 528b in FIGS. 10-14 ) and drives the needle carrier assembly 516, needle hub 518, and insertion element 520 proximally from the distal insertion position. When the needle carrier assembly 516 reaches the proximal retracted position, the needle carrier retaining element 542 of the holder 522 engages the needle carrier assembly 516, thereby maintaining the needle carrier assembly 516, needle hub 518, and insertion element 520 in a locked retracted position that restricts access to the insertion element 520. The needle carrier retaining element 542 may comprise, for example, an arm, a deflection element, a tab, a detent, a snap, or any other feature capable of retaining function. In this retracted position, the needle carrier assembly 516, needle hub 518, and insertion element 520 are prevented from moving distally.

[0087] A further description of some aspects of the operation of applicator 500 follows below with reference to Figures 10-12, which illustrate several cross-sectional views of applicator 500 of Figures 5 and 6 in operation, according to some embodiments. Figures 10-12 may correspond, for example, to applicator 500 cut along section line B-B' shown in Figure 5. For ease of illustration, needle hub 518 and insertion element 520 are not shown in Figures 10-12.

[0088] FIG. 10 illustrates the state of the applicator 500 before actuation. For ease of illustration, the on-skin sensor assembly 508 is not illustrated in FIG. 10. The holder 522 includes spring retaining elements 528a, 528b configured to contact the first end of the second spring 526 and retain it in a pre-actuated state, e.g., during insertion, while the second end of the spring 526 is in contact with the needle carrier assembly 516. The spring retaining elements 528a, 528b may include, for example, arms, deflection elements, tabs, detents, snaps, or any other feature capable of retaining functionality. While two spring retaining elements 528a, 528b are shown, at least one spring retaining element is contemplated. In some embodiments, the applicator 500 may include one spring retaining element, as shown in FIGS. 21-24. In some embodiments, the applicator 500 may include three spring retaining elements. In some embodiments, applicator 500 may include four spring retaining elements. In some embodiments, spring retaining elements 528a, 528b are deflectable arms, rigid arms, deformable features, snaps, catches, or hooks. In some embodiments, spring retaining elements 528a, 528b may be actively deflected by one or more features within applicator 500.

[0089] Needle carrier assembly 516 includes backstop features 544a, 544b configured to prevent lateral deflection of spring retaining elements 528a, 528b in a proximal starting position, for example, at least during insertion, thereby supporting retention of second spring 526 between spring retaining elements 528a, 528b and holder 522 until retraction. While two backstop features are illustrated, any number of backstop features is contemplated. The number of backstop features may equal the number of spring retaining elements.

[0090] FIG. 13 illustrates a close-up view of spring retaining element 528b and backstop feature 544b. In FIG. 13, first spring 524 drives holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 distally toward the distal insertion position. Backstop feature 544b is shown engaged with spring retaining element 528b, preventing spring retaining element 528b from deflecting laterally, thereby preventing second spring 526 from releasing. As shown in FIG. 13, the proximal end of spring retaining element 528b can be offset from the distal end of backstop feature 544b by a distance α. In some embodiments, distance α is the length required for spring retaining element 528b to traverse along backstop feature 544b so that spring retaining element 528b passes through backstop feature 544b. Backstop feature 544b may feature a beveled surface to guide spring retaining element 528b. The distal end of needle carrier assembly 516 and the distal end of holder 522 may be offset from one another by at least the same distance α to allow spring retaining element 528b to traverse distally over backstop feature 544b.

[0091] It can be appreciated that the frictional force between the corresponding contact surfaces of the backstop feature 544b and the spring retaining element 528b can at least partially determine the amount of force required to release the spring retaining element 528b from the backstop feature 544b. This force can allow lateral deflection of the spring retaining element 528b and, therefore, expansion of the second spring 526. In some embodiments, the amount of force is at least 0.1 pounds. In some embodiments, the amount of force is at least 0.5 pounds. In some embodiments, the amount of force is at least 1 pound. In some embodiments, the amount of force is at least 2 pounds. In some embodiments, the amount of force is at least 3 pounds. In some embodiments, the amount of force is at least 4 pounds. In some embodiments, the amount of force is at least 5 pounds.

[0092] Although the figure shows backstop feature 544b preventing lateral deflection of spring retaining element 528b in a radially outward direction, it is contemplated that the opposite structural relationship may be achieved. For example, the angled surface of spring retaining element 528b may be inverted to face the opposite direction as shown in FIG. 13 . Additionally, the angled surface of spring retaining element 528b may be biased radially inward against backstop feature 544b by second spring 526. In such an embodiment, backstop feature 544b may be located radially inward of spring retaining element 528b.

[0093] Thus, in some embodiments, the material utilized to form holder 522 and needle carrier assembly 516 may be selected based on the amount of force desired to release spring retaining element 528b for lateral deflection. Examples of such materials include polycarbonate, ABS, PC / ABS, polypropylene, HIPS (High Impact Polystyrene), polybutylene terephthalate (PBT), polyoxymethylene (POM), acetal, polyacetal, polyformaldehyde, PTFE, high density polyethylene (HDPE), ultra-high-molecular-weight polyethylene (UHMWPE), nylon, polyethylene terephthalate (PET), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), silicone thermoplastic elastomer (TPSiv), cycloolefin polymer (COP), cycloolefin copolymer (COC), and / or liquid-crystal polymer (LCP).

[0094] The angle θ of the portion of the spring retaining element 528b that contacts the second spring 526 can also affect the amount of frictional force required to laterally deflect the spring retaining element 528b and, therefore, release the second spring 526. Therefore, the angle θ may be selected based on the desired amount of force required to laterally deflect the spring retaining element 528b sufficiently to release the second spring 526. In some embodiments, the angle θ is at least 1 degree relative to a vertical axis of the spring retaining element 528b. In some embodiments, the angle θ is at least 5 degrees. In some embodiments, the angle θ is at least 10 degrees. In some embodiments, the angle θ is at least 15 degrees. In some embodiments, the angle θ is at least 20 degrees. In some embodiments, the angle θ is approximately 30-45 degrees. Additionally, the force profile of the second spring 526 can affect the target amount of frictional force required to laterally deflect the spring retaining element 528b. Thus, in some embodiments, the force profile of the second spring 526 may be considered when selecting one or both of the materials for forming the holder 522 and the needle carrier assembly 516, as well as the angle θ of the portion of the spring retaining element 528b that contacts the second spring 526.

[0095] The angle β of the spring retaining element 528b relative to the vertical axis can also affect the amount of frictional force that causes the spring retaining element 528b to deflect laterally and thus release the second spring 526. By contacting the spring retaining element 528b, the second spring 526 can apply a force to the spring retaining element 528b at a distance d from the bottom of the spring retaining element 528b, which creates a torque moment sufficient to induce lateral deflection of the spring retaining element 528b.

[0096] 13 further illustrates needle carrier assembly 516 with a flexure element 546 configured to contact spring retaining element 528b and maintain spring retaining element 528b in a laterally flexed orientation after second spring 526 initially deflects spring retaining element 528b and sufficiently drives needle carrier assembly 516 in a proximal direction, as shown in more detail in FIG. 14. Flexure element 546 may prevent spring retaining element 528b from contacting the windings of second spring 526 while second spring 526 is extended, smoothing the operation of applicator 500 and preventing energy designed to be released by second spring 526 to drive needle carrier assembly 526 in a proximal direction from being absorbed by undesired contact with spring retaining element 528b during release of second spring 526.

[0097] In some embodiments, the angle θ of the portion of the spring retaining element 528b in contact with the second spring 526 may be substantially 90° (e.g., flat), and the flexure element 546 may have a sloped or angled surface in contact with the spring retaining element 528b in the position illustrated in Figure 13. In such embodiments, in addition to the functionality described above, the flexure element 546 may be configured to initially deflect the spring retaining element 528b when the first spring 524 drives the holder 522 from the position illustrated in Figure 13 to the position illustrated in Figure 14.

[0098] In some embodiments, inner housing 506 may include a protrusion 548 extending distally from inner housing 506. Protrusion 548 may be configured to contact at least one of spring retaining elements 528a, 528b and backstop features 544a, 544b in a pre-actuated state such that spring retaining elements 528a, 528b are prevented from deflecting laterally until holder 522 and needle carrier assembly 516 have translated distally at least a predetermined minimum distance. Protrusion 548 may thus provide a measure of drop protection to prevent applicator 500 from prematurely firing in response to a concussive shock due to being dropped prior to intended actuation.

[0099] Returning to FIG. 10 , the inner housing 506 may further comprise an engagement element 550 configured to engage a protrusion 552 of the needle carrier assembly 516 when the needle carrier assembly 516 translates distally beyond a predetermined threshold, thereby preventing the needle carrier assembly 516 from translating distally beyond the predetermined threshold. This is contemplated to ensure retraction of the needle carrier assembly in the event of an air or dry firing that is somehow activated when the applicator 500 is not held against the recipient's skin. In some embodiments, the predetermined threshold may correspond to the distal end of the needle carrier assembly 516 extending beyond a point proximal to the distal end of the inner housing 506 to a point substantially coincident with the distal end of the inner housing 506 or to a point distal to the distal end of the inner housing 506. In some embodiments, the engagement element 550 comprises a hook, a U-shaped structure, a loop, a protrusion, or any other structure capable of engaging with the protrusion 552 as described above.

[0100] 11 illustrates the applicator 500 after actuation, at the beginning of the force retract feature process at or near a distal insertion position where the on-skin sensor assembly 508 may contact the recipient's skin. The first spring 524 drives the holder 522, needle carrier assembly 516, needle hub 518, insertion element, and on-skin sensor assembly 508 distally toward the distal insertion position. During proper operation, the holder 522 and on-skin sensor assembly 508 should be pressed against the recipient's skin. However, FIG. 11 also illustrates a dry-fire condition in which the applicator 500 is not properly pressed against the recipient's skin prior to triggering the applicator 500. Thus, when first spring 524 drives holder 522 and needle carrier assembly 516 distally beyond a predetermined threshold, engagement element 550 contacts protrusion 552, thereby preventing needle carrier assembly 516 from further moving distally, while holder 522 is driven distally far enough so that backstop features 544 a, 544 b of needle carrier assembly 516 no longer contact spring retaining elements 528 a, 528 b in the distal insertion position, thereby releasing the first end of second spring 526 and initiating retraction, even when applicator 500 is dry fired. The insertion force provided by first spring 524 may be sufficient to further overcome the frictional force between the corresponding contact surfaces of backstop feature 544 b and spring retaining element 528 b.

[0101] 14 , the first spring 524 urges the holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 in a distal direction against the recipient's skin. As the first spring 524 urges the holder 522, needle carrier assembly 516, and on-skin sensor assembly 508 against the recipient's skin, the skin provides a counterforce to the force generated by the first spring 524. The skin may counter the force of the first spring 524 and bias against the distal end of the on-skin sensor assembly 508. Because the distal end of the holder 522 is offset from the distal end of the on-skin sensor assembly 508, as shown in FIG. 13 , the counterforce provided by the skin is transmitted to the holder 522 as the first spring 524 continues to urge the holder 522 toward the skin while the on-skin sensor assembly 508 is pressed against the skin. The reaction force provided by the skin allows spring retaining element 528b to be displaced past backstop feature 544b. Once spring retaining element 528b clears distance α past backstop feature 544b, second spring 526 can deflect spring retaining element 528b laterally, thereby releasing second spring 526 to drive needle carrier assembly 516 proximally. Alternatively, as described above in connection with FIG. 13 , if angle θ of the portion of spring retaining element 528b in contact with second spring 526 is substantially 90° (e.g., flat), the angled surface or sloped surface of flexure element 546 in contact with spring retaining element 528b can deflect spring retaining element 528b sufficiently to release second spring 526, thereby driving needle carrier assembly 516 proximally.

[0102] In some embodiments, the engaging element 550 can engage the protrusion 552 even when the applicator 500 is pressed against the user's skin. In such embodiments, the engaging element 550 engages the protrusion 552 when the first spring 524 drives the holder 522, the needle carrier assembly 516, and the on-skin sensor assembly 508 against the recipient's skin. As explained above, the engaging element 550 prevents the needle carrier assembly 516 from moving distally when the engaging element 550 engages the protrusion 552. This allows the spring retaining elements 528a, 528b to move away from the backstop features 544a, 544b, allowing the second spring 526 to release. The engagement of the engaging element 550 with the protrusion 552 may add additional force to the reaction force provided by the skin, thus increasing the energy required to overcome the frictional engagement between the spring retention elements 528a, 528b and the backstop features 544a, 544b. In some cases, the engagement of the engaging element 550 with the protrusion 552 provides an immediate impact force that converts at least a portion of the initial energy of the first spring 524 into the energy necessary to overcome the frictional engagement between the spring retention elements 528a, 528b and the backstop features 544a, 544b. It is contemplated that such embodiments may benefit users with softer skin or a higher body fat percentage.

[0103] Returning to FIG. 12, which illustrates applicator 500 in operation, needle carrier assembly 516 is urged proximally retracted by second spring 526 as indicated by arrow 554 . In FIG. 12 , when the on-skin sensor assembly 508 is in contact with the recipient's skin with the backstop features 544a, 544b no longer securing the spring retaining elements 528a, 528b, the first end of the second spring 526 presses against the spring retaining elements 528a, 528b with sufficient force to deflect the spring retaining elements 528a, 528b to a distal insertion position, allowing the second spring 526 to clear the spring retaining elements 528a, 528b and drive the needle carrier assembly 516 in a proximal direction, thereby maintaining the needle carrier assembly 516, needle hub 518 (see FIGS. 7-9), and insertion element 520 (see FIGS. 7-9) in a locked, retracted position, even in the event of a dry fire.

[0104] 15 and 16 illustrate close-up views of some features of an applicator, such as applicator 500, according to some embodiments.

[0105] In Figure 15, a first spring 524 (see Figures 6-12) urges the holder 522 and needle carrier assembly and on-skin sensor assembly 508 in a distal direction indicated by arrow 556, toward a distal insertion position. A retaining element 534b of the needle carrier assembly is releasably coupled to the on-skin sensor assembly 508. As illustrated, during insertion and near the distal insertion position, the holder 522 contacts the spring retaining element 534b, preventing the spring retaining element 534b from deflecting laterally, thereby securely securing the on-skin sensor assembly 508 to the needle carrier assembly.

[0106] In FIG. 16, the second spring 526 (see FIGS. 6-12) is urging the needle carrier assembly 516 proximally from the distal insertion position. The holder 522 has been driven sufficiently distally that, at the distal insertion position, the holder 522 is no longer in contact with the wearable holding element 534b. The wearable holding element 534b is therefore free to flex laterally, thereby releasing the on-skin sensor assembly 508 from the wearable holding element 534b and therefore from the needle carrier assembly 516. The needle carrier assembly 516 is now driven proximally by the second spring 526, while the on-skin sensor assembly 508 is secured to the recipient's skin. Further, in some embodiments, the holder 522 is driven to a distal insertion position and is substantially held in that position by the first spring 524 so that the holder 522 can press against one or both of the on-skin sensor assembly 508 or the adhesive patch of the on-skin sensor assembly 508 to support one or both during attachment to the recipient's skin.

[0107] Figure 17 illustrates a perspective, partial cutaway view of the needle carrier assembly 516, needle hub 518, and on-skin sensor assembly 508 of the applicator 500 of Figures 5 and 6, according to some embodiments. Figure 18 illustrates a cross-sectional view of the needle hub 518 and on-skin sensor assembly 508, according to some embodiments. Figure 19 illustrates a top view of a portion of the needle carrier assembly 516 and needle hub 518, according to some embodiments. The following is a description of these features with reference to Figures 17-19.

[0108] On-skin sensor assembly 508 includes sensor assembly opening 560. Needle hub 518 is configured to couple insertion element 520 to needle carrier assembly 516 and to substantially maintain a desired orientation of insertion element 520 during insertion of a sensor of on-skin sensor assembly 508 into the skin of a recipient.

[0109] The needle hub 518 comprises a plurality of upper arms 562a, 562b, a plurality of lower arms 564a, 564b, and a base 566. While two upper arms and two lower arms are illustrated, any number of arms is contemplated, such as a single upper and lower arm. In some embodiments, the upper arms 562a, 562b and the lower arms 564a, 564b may be flexible such that when the needle hub 518 is coupled to the needle carrier assembly 516, the upper arms 562a, 562b and the lower arms 564a, 564b secure the needle hub 518 in a desired orientation relative to the needle carrier assembly 516. For example, the upper arms 562a, 562b may be configured to flex radially inward when disposed through a carrier opening 568 in the needle carrier assembly 516, such that the upper arms 562a, 562b contact an upper surface of the needle carrier assembly 516 adjacent the carrier opening 568, and the lower arms 564a, 564b contact a lower surface of the needle carrier assembly 516 adjacent the carrier opening 568. Such an arrangement allows for a compliant fit between the needle carrier assembly 516 and the needle hub 518, with the lower arms 564a, 564b flexing to allow the upper arms 562a, 562b to expand after clearing the surface of the carrier opening 568. The lower arms 564a, 564b can partially or completely relax to bias the needle hub distally and reduce the clearance between the needle hub and the needle carrier that would otherwise exist in a non-compliant fit. Additionally, the upper arms 562 a , 562 b and lower arms 564 a , 564 b also help maintain contact between the base 566 and the top surface of the on-skin sensor assembly 508 .

[0110] The base 566 includes an anti-rotation feature. The anti-rotation feature may comprise a key having a shape complementary to at least a portion of the sensor assembly opening 560 of the on-skin sensor assembly 508 and may be configured to prevent rotation of the base 566 within the sensor assembly opening 560, for example, to substantially prevent rotation of the needle hub 518 relative to the on-skin sensor assembly 508 about an axis 567 parallel to the insertion element 520. Additionally or alternatively, a top surface of the needle carrier assembly 516 adjacent the carrier opening 568 may include grooves 570 configured to receive the upper arms 562 a, 562 b when the upper arms 562 a, 562 b are disposed through the carrier opening 568 in an orientation complementary to the orientation of the grooves 570, thereby securing the needle hub 518 relative to the needle carrier assembly 516, as illustrated in FIG.

[0111] In some embodiments, the base 566 further comprises a substantially flat surface configured, in some cases, to mate with a top or proximal surface of the on-skin sensor assembly 508 and maintain the insertion element 520 in a substantially perpendicular orientation relative to the top surface of the on-skin sensor assembly 508 when the anti-rotation feature of the base 566 is engaged within the sensor assembly opening 560 of the on-skin sensor assembly 508.

[0112] Based at least on the above-described features of the needle hub 518, the on-skin sensor assembly 508, and / or the needle carrier assembly 516, the base 566 allows for easy assembly during manufacturing, including, but not limited to, proper alignment and pre-assembly of the insertion element 520 onto the on-skin sensor assembly 508, and / or the ability to easily engage the assembly of the needle hub 518, the insertion element 520, the sensor, and the on-skin sensor assembly 508 with other portions of the assembled applicator 500.

[0113] 20A and 20B illustrate perspective views of locking features for insertion elements in the form of needles 600a, 600b for use in an applicator for an analyte sensor system, according to some embodiments. For example, needle 600a in FIG. 20A includes a locking feature comprising a ridge 602 configured to mate with a complementary feature in, for example, needle hub 518. Alternatively, needle 600b in FIG. 20B includes a locking feature comprising a groove 604 configured to mate with a complementary feature in, for example, needle hub 518.

[0114] In yet another alternative, any insert element described in this disclosure may comprise a locking feature that, for example, heat stakes the selected insert element to the needle hub 518. In yet another alternative, any insert element described in this disclosure may comprise a locking feature that, for example, comprises one or more friction-fit or snap-fit ​​elements that secure the selected insert element to the needle hub 518. In yet another alternative, any insert element described in this disclosure may comprise a locking feature that, for example, comprises complementary clamshell elements on the selected insert element and the needle hub 518 that are configured to mate with one another. In yet another alternative, any insert element described in this disclosure may comprise a locking element that, for example, comprises one or more insert-molded elements configured to couple the selected insert element to the needle hub 518.

[0115] During manufacturing, the applicator 500 may be assembled in stages. For example, without limitation, if present, the first barrier layer 512 may be affixed to the inner housing 506. The insertion element 520 may be coupled to the needle hub 518, which may then be coupled to the on-skin sensor assembly 508. The second spring 526 may be installed in the holder 522 or the needle carrier assembly 516, which may then be disposed in the holder 522 and attached to the needle hub 518 and the on-skin sensor assembly 508 via wearable holding elements 534a, 534b. The first spring 524 may be disposed in the holder 522 and then installed in the inner housing 506. The inner housing 506 may be inserted into and secured to the outer housing 504. If present, the second barrier layer 530 may be affixed to the inner housing 506. If a separate element, actuation element 502 may be disposed within outer housing 504. Any labeling, sterilization, and / or packaging may then be applied to applicator 500.

[0116] 21-23 illustrate several cross-sectional views and various features and operating positions of yet another applicator 700 for an on-skin sensor assembly of an analyte sensor system, according to some embodiments.

[0117] Applicator 700 may include an outer applicator housing 504 that includes actuating element 502. Outer applicator housing 504 may be configured to translate distally under force applied by a recipient of applicator 700, thereby aligning actuating element 502 in a position that allows applicator 700 to fire, an alignment illustrated by FIG. 21. As discussed above in connection with applicator 500, in some embodiments, actuating element 502 may be disposed anywhere, such as on the top, upper side, lower side, or any other location of applicator 700.

[0118] The applicator 700 further comprises an inner housing 506 configured to house one or more mechanisms utilized to apply the on-skin sensor assembly 508 to the skin of a recipient. A distal surface 510 of the bottom opening of the inner housing 506 may define a bottom surface of the applicator 700. In some embodiments, when the applicator 700 is pressed against the skin of a recipient, the skin may deform substantially convexly at the distal surface 510 such that at least a portion of the surface of the skin disposed at the bottom opening of the applicator housing 506 extends beyond the plane defined by the distal surface 510, in a proximal direction, and into the bottom opening of the inner housing 506.

[0119] 21-23, the inner housing 506 may include a spring 536 configured to contact the outer housing 504 and maintain a predetermined spacing between the outer housing 504 and the inner housing 506 in a pre-actuated orientation (see FIG. 7). The spring 536 may be a compression spring, a leaf spring, a flex arm spring, a piece of foam or rubber, or the like. In some other embodiments, the outer housing 504 may include the spring 536, and the spring 536 may be configured to contact the inner housing 506.

[0120] The applicator 700 may further comprise a needle carrier assembly 702. The needle carrier assembly 702 comprises wearable holding and / or alignment elements 534a, 534b that are configured to pass through the holder 704 and to releasably couple the on-skin sensor assembly 508 to the holder 704 and / or the needle carrier assembly 702. Although two wearable holding and / or alignment elements are illustrated, any number of wearable holding and / or alignment elements is contemplated.

[0121] The applicator 700 further comprises a needle hub 518 configured to couple an insertion element 520 to the needle carrier assembly 702. The insertion element 520 is configured to insert a sensor of the on-skin sensor assembly 508 into the skin of a recipient. In some embodiments, the insertion element 520 comprises a needle, such as an open-side needle, a needle with a tip deflection, a curved needle, a polymer-coated needle, a hypodermic needle, or any other suitable type of needle or structure. In still other embodiments, the insertion element 520 may be integrally formed with the sensor, or the insertion element 520 may be sufficiently rigid to be inserted partially into the skin of a recipient with minimal or no structural support.

[0122] The applicator 700 may further include a holder 704 releasably coupled to the needle carrier assembly 702, the holder 704 configured to guide the on-skin sensor assembly 508 while coupled to the needle carrier assembly 702, for example, during translation from at least a proximal position to a distal insertion position. As described above in connection with the applicator 500, once the on-skin sensor assembly 508 is disposed on the skin of the recipient, the on-skin sensor assembly 508 may be removed or released from the holder 704 and / or the needle carrier assembly 702.

[0123] The applicator 700 may further include an insertion assembly configured to translate the insertion element 520, the needle hub 518, and the needle carrier assembly 702 distally from a proximal position to a distal insertion position. Such an insertion assembly may include a first spring 524. The first spring 524 may be a compression spring or any suitable type of spring and may have a first end that contacts or is coupled to the inner applicator housing 506 and a second end that contacts or is coupled to the holder 704. The first spring 524 is configured to translate the holder 704, the needle carrier assembly 702, the needle hub 518, the insertion element 520, and the on-skin sensor assembly 508 distally to the distal insertion position upon actuation of the insertion assembly. At substantially the distal insertion position, the needle carrier assembly 702 may be separated from the holder 704 and the on-skin sensor assembly 508.

[0124] The applicator 700 may further include a retraction assembly configured to translate the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a proximal direction from a distal insertion position to a proximal retracted position. In some embodiments, the initial proximal position may be the same as the proximal retracted position. In other embodiments, the initial proximal position may be different from the proximal retracted position. Such a retraction assembly may include a second spring 706. The second spring 706 may be a compression spring or any suitable type of spring and may have a first end that contacts or couples with the holder 704 and a second end that includes a tang 708 (e.g., a spring portion or spring end) disposed substantially along the diameter of the second spring 706 and that contacts or couples with a spring retaining element 710 of the holder 704 at least until retracted. The spring retaining element 710 may include, for example, an arm, a deflection element, a tab, a detent, a snap, or any other feature capable of a retaining function. Spring retaining element 710 may have substantially the same form and function as spring retaining elements 528a, 528b of applicator 500, except as described below. Second spring 706 is configured to translate needle carrier assembly 702, needle hub 518, and insertion element 520 proximally from a distal insertion position to a proximal retracted position. Tang 708 of second spring 706 is released from spring retaining element 710 at the distal insertion position when spring retaining element 710 is not backed up by backstop element 712 and in response to the tang 708 of second spring 706 pressing against spring retaining element 710 with a force above a predetermined threshold sufficient to overcome and deflect spring retaining element 710.

[0125] Needle carrier assembly 702 further includes a backstop feature 712 configured to prevent lateral movement of spring retaining element 710 of holder 704, at least in a proximal pre-actuation position, thereby supporting retention of second spring 706 between spring retaining element 710 and holder 704 until retraction. In the orientation shown in FIG. 21 , second spring 706 exerts a force against spring retaining element 710, but backstop feature 712 prevents lateral deflection of retaining element 710.

[0126] Holder 704 further comprises needle carrier retaining element 542, which may comprise a deflectable arm, a rigid arm, a deformable feature, a snap, a catch, or a hook. Needle carrier retaining element 542 is configured to engage needle carrier assembly 702 when needle carrier assembly 702 reaches the proximal retracted position after actuation, thereby maintaining needle carrier assembly 702, needle hub 518, and insertion element 520 in a locked, retracted position and restricting access to insertion element 520.

[0127] Although not illustrated in Figures 21-23, inner housing 506 of applicator 700 may further include engagement element 550, and needle carrier assembly 702 may further include protrusion 552, and may function substantially as described above in connection with at least Figures 10-12.

[0128] 21-23, inner housing 506 of applicator 700 may further include a protrusion extending distally therefrom, substantially like protrusion 548 described above. Similar to that described above in connection with FIG. 13, this protrusion may be configured to contact at least one of spring retaining element 710 and backstop mechanism 712 in a pre-actuated state, such that spring retaining element 710 is prevented from deflecting laterally until holder 704 and needle carrier assembly 702 have translated distally at least a predetermined minimum distance. Thus, the protrusion may provide a means of drop protection to prevent premature firing of applicator 700 in response to a concussive shock due to being dropped prior to intended actuation.

[0129] Applicator 700 functions substantially similarly to applicator 500, except that instead of utilizing spring retaining elements 528a, 528b disposed along the outside of the second coil of spring 526 and configured to contact and retain the coil of second spring 526, applicator 700 utilizes spring retaining element 710 disposed along the inside of second spring 706 and configured to contact and retain a tang 708 of second spring 706 along the diameter of second spring 706. Disposing spring retaining element 710 within and substantially along the center of second spring 706, rather than along the outside of second spring 706, further ensures that spring retaining element 710 does not contact the coil of second spring 706 as second spring 706 extends during retraction, thereby facilitating operation of applicator 700. Additionally, the arrangement including spring retaining element 710 as opposed to spring retaining elements 528a, 528b reduces the risk and difficulty of ensuring that multiple spring retaining elements are triggered or overcome substantially simultaneously.

[0130] 21 illustrates the state of the applicator 700 before actuation, according to some embodiments. The holder 704, needle carrier assembly 702, needle hub 518, insertion element 520, on-skin sensor assembly 508, first spring 524, and second spring 526 are all shown in the pre-actuation position.

[0131] The retaining element 532 of the holder 704 contacts the inner housing 506, thereby securing the holder 704, and therefore the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508, in a pre-activated state.

[0132] The backstop feature 712 of the needle carrier assembly 702 contacts the spring retaining element 710 to prevent the spring retaining element 710 from deflecting laterally, thereby ensuring that the spring retaining element 710 retains the tang 708 of the second spring 706 in the loaded or pre-actuated position shown.

[0133] Actuation of applicator 700 may involve the recipient pressing applicator 700 against their skin with sufficient force to translate outer housing 504 toward and distally relative to inner housing 506 until actuation element 502 is aligned with insertion assembly retaining element 532 of holder 704, as shown in FIG. 21 . Once such alignment is achieved, the recipient may initiate actuation element 502, thereby sufficiently deflecting insertion assembly retaining element 532 to release holder 704 from inner housing 506. In some other embodiments, applicator 700 may be configured such that actuation element 502 may be first actuated, but the actual insertion is not triggered until outer housing 504 has been sufficiently translated toward and distally relative to inner housing 506. In yet other embodiments, the actuating element 502 may be biased toward the center of the applicator 700 such that the actuating element 502 does not need to be explicitly actuated by the recipient, but instead may be configured to automatically begin insertion when the outer housing 504 is sufficiently translated distally toward and relative to the inner housing 506.

[0134] 22 illustrates the applicator 700 after actuation and during insertion, according to some embodiments. The first spring 524 drives the holder 704, and thus the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508, distally toward the distal insertion position. FIG. 22 illustrates the on-skin sensor assembly 508 in contact with the recipient's skin, but the holder 704 has not yet been fully driven by the first spring 524 into contact with the on-skin sensor assembly 508 or the recipient's skin.

[0135] In some embodiments, the mass of each of the holder 704, needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508 may be specifically designed to reduce or substantially eliminate the tendency of the needle carrier assembly 702, needle hub 518, insertion element 520, and on-skin sensor assembly 508 to become dislodged from the holder 704 while being driven distally during insertion. In some embodiments, the force exerted by the first spring 524 may further be selected to be sufficient for proper operation of the applicator 500, but not so great as to further exacerbate such inertia-triggered separation described above. In some embodiments, the spring (not shown) may be configured to exert a force against a portion of the needle carrier assembly 516, e.g., in a distal direction, sufficient to prevent inertia-triggered separation of the needle carrier assembly 702 from the holder 704 during insertion.

[0136] 23 illustrates the applicator 700 after actuation and at or near the distal insertion position, according to some embodiments. The first spring 524 drives the holder 704, needle carrier assembly 702, and on-skin sensor assembly 508 distally to the distal insertion position. Because the first spring 524 has driven the holder 704 a shorter distance distally than the needle carrier assembly 702, the backstop feature 712 no longer contacts the spring retaining element 710, allowing the second spring 706 (e.g., tang 708) to deflect the spring retaining element 710 laterally, thereby releasing the second spring 706 and driving the needle carrier assembly 702 proximally. Alternatively, similar to that described above in connection with applicator 500 of FIG. 13 , where the angle θ of the portion of spring retaining element 710 in contact with tang 708 of second spring 706 is substantially 90° (e.g., flat), spring retaining element 710 may be biased to automatically deflect sufficiently to release second spring 526 when backstop feature 712 no longer contacts spring retaining element 710, thereby releasing second spring 526 to drive needle carrier assembly 702 in a proximal direction. Although not shown in FIGS. 21-23 , inner housing 506 may further comprise engagement element 550 configured to engage protrusion 552 of needle carrier assembly 702 and function substantially as described above in connection with at least FIGS. 10-12 . In some embodiments, a stop feature (not shown) may be disposed on the bottom of applicator 700, for example, on a distal portion of inner housing 506. Such a stop feature may be configured to contact one or more of the on-skin sensor assembly 508, the needle carrier assembly 702, or the holder 704 at the distal insertion position.

[0137] When the second spring 706 is released, the second spring 706 is configured to drive the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a proximal direction. Although not shown in FIG. 23 , when the needle carrier assembly 702 moves to the proximal retracted position, the needle carrier retaining element 542 can engage the needle carrier assembly 702, thereby retaining the needle carrier assembly 702, the needle hub 518, and the insertion element 520 in a locked retracted position that restricts access to the insertion element 520.

[0138] 24 illustrates a perspective view of the holder 704, first spring 524, and second spring 706 of the applicator 700, according to some embodiments. FIG. 24 shows the spring retention element 710 with the retention tang 708 of the second spring 706 oriented within the applicator 700 prior to retraction.

[0139] During manufacturing, the applicator 700 may be assembled in stages. For example, and without limitation, if present, the first barrier layer 512 (see FIG. 6 ) may be affixed to the inner housing 506, as described above in connection with the applicator 500. The insertion element 520 may be coupled to the needle hub 518, which may then be coupled to the on-skin sensor assembly 508. The second spring may be installed in the holder 704 or the needle carrier assembly 702, and the needle carrier assembly 702 may then be disposed in the holder 704 and attached to the needle hub 518 and the on-skin sensor assembly via the wearable holding elements 534 a, 534 b. The first spring 524 may be disposed in the holder 704, which may then be installed in the inner housing 506. The inner housing 506 may be inserted into the outer housing 504 and secured. If present, second barrier layer 530 (see FIG. 6 ) may be affixed to inner housing 506, as described above in connection with applicator 500. If a separate element, actuation element 502 may be disposed within outer housing 504. Any labeling, sterilization, and / or packaging may then be applied to applicator 700.

[0140] When actuated, the applicators disclosed herein may insert a transcutaneous analyte sensor into the recipient's skin by utilizing an insertion element (such as insertion element 520). Referring to FIG. 25A , the insertion element 520 may drive the transcutaneous analyte sensor 802 of the on-skin sensor assembly 800 into the recipient's skin, with the transcutaneous analyte sensor 802 extending along the channel of the insertion element 520. The insertion element 520 may be withdrawn, with the transcutaneous analyte sensor 802 remaining within the skin, as depicted in FIG. 25B . The patch 804 or other component of the on-skin sensor assembly 800 may include a surface 806 (which may be referred to as a first surface) for engaging the skin. The surface may include, for example, an adhesive surface. The adhesive may be configured to adhere to the skin. Additional adhesive information is described in U.S. Patent No. 11,219,413, filed August 25, 2015. The entire contents of U.S. Patent No. 11,219,413 are incorporated herein by reference. The patch 804, in embodiments, may be coupled to the housing of the on-skin sensor assembly 800. The transcutaneous analyte sensor 802 may be coupled to the housing of the on-skin sensor assembly 800.

[0141] A liner (not shown in FIGS. 25A-25B ) may be positioned on surface 806 in embodiments. The liner may cover surface 806 and protect surface 806 from damage, deterioration, or other adverse effects. The liner may include, for example, a sheet of material that covers surface 806. The liner may have a proximal surface that contacts surface 806 and a distal surface facing opposite the proximal surface. The liner in embodiments may be configured to reduce the likelihood that exposed surface 806 will deteriorate or otherwise lose its adhesive properties prior to placement. For example, during a sterilization process using a gas or other sterilizing material, the liner may reduce the likelihood of surface 806 deteriorating. The sterilizing gas may include ethylene oxide (EtO) or another form of sterilizing gas as desired.

[0142] However, the liner should be separated from the surface 806 before placing the on-skin sensor assembly 800 on the skin. FIGS. 26A-26G illustrate one embodiment of a system for placing an on-skin wearable medical device on the skin. The system includes an applicator 900 having an applicator housing 902 configured to hold the on-skin wearable medical device and a placement mechanism configured to place the on-skin wearable medical device on the skin. The applicator housing 902 may be configured similarly to the applicator embodiments disclosed herein, including having an outer housing 904 and an inner housing 906 as disclosed with respect to the embodiment of FIGS. 5-24 . The outer housing 904 may be configured similarly to the outer housing 504, for example, and the inner housing may be configured similarly to the inner housing 506. The applicator housing 902, in embodiments, may be configured to be gripped by a user. Various other configurations of the applicator housing may be utilized as desired.

[0143] The applicator housing 902 may include an internal cavity 903 for holding an on-skin wearable medical device. The housing 902 can include an opening 905 at an end portion 907 of the internal cavity 903 for allowing the on-skin wearable medical device to be placed therethrough. The internal cavity 903 can include a proximal end portion 909 that can include the on-skin wearable medical device coupled to a needle carrier assembly.

[0144] The positioning mechanism may be configured similarly to other forms of positioning mechanism disclosed herein. The positioning mechanism may be configured similarly to the positioning mechanism disclosed with respect to the embodiment of Figures 5-24. For example, in embodiments, the positioning mechanism may include one or more retention elements for holding the on-skin wearable medical device and releasing the on-skin wearable medical device from the housing 902 onto the skin. The positioning mechanism may include an insertion assembly for inserting at least a portion of the on-skin wearable medical device into the skin. The insertion assembly may insert an insertion element (e.g., a needle) into the skin. The positioning mechanism may drive the insertion element into the skin once the positioning mechanism places the on-skin wearable medical device on the skin. The positioning mechanism may include a retraction assembly for retracting the insertion element from the skin. Other forms of positioning mechanisms may be utilized in embodiments as desired.

[0145] Applicator 900 may include actuation element 908, which may operate similarly to actuation element 502. Applicator 900 may include needle carrier assembly 910, which may operate similarly to needle carrier assembly 516. Applicator 900 may include holder 912, which may operate similarly to holder 522. Applicator 900 may include a hub (e.g., needle hub 914), which may operate similarly to needle hub 518. Applicator 900 may include insertion element 915 (e.g., a needle), which may operate similarly to insertion element 520. Applicator 900 may include springs 916, 918, which may operate similarly to springs 524, 526, respectively. Applicator 900 may include retention elements 920a, 920b, which may operate similarly to retention elements 534a, 534b, respectively. Additional components of the applicator shown in FIGS. 5-24 may be utilized with applicator 900. Applicator 900 may be of a similar style and provide similar functionality to the applicators shown in Figures 5-24.

[0146] The applicator 900 may be utilized to place an on-skin wearable medical device on the skin. The on-skin wearable medical device may include, for example, the on-skin sensor assembly 508 shown in FIG. 6, which may include a housing, a transcutaneous analyte sensor coupled to the housing, an electronics unit, and a patch 922. The on-skin sensor assembly may have a configuration such as that shown in FIGS. 2A-4, or other configurations as desired.

[0147] The on-skin sensor assembly 508 may include a surface 924 (which may be referred to as a first surface) (shown in FIG. 26F ) that may be utilized to engage the skin. Thus, the surface 924 may contact the skin and hold the on-skin sensor assembly 508 against the skin. The surface 924 may be positioned on a patch of the on-skin sensor assembly 508. The surface 924 may comprise a distal surface of the on-skin sensor assembly 508, which in embodiments is opposite a proximal surface. In embodiments, the surface 924 may comprise an adhesive surface as disclosed herein.

[0148] A liner 926 (marked in FIG. 26G) may be positioned on and cover the surface 924 and may protect the surface 924 from damage, deterioration, or other adverse effects as disclosed herein. However, the liner 926 should be separated from the surface 924 before placing the on-skin sensor assembly 508 on the skin.

[0149] 26A , the system may include a liner removal component 928. The liner removal component 928 may be configured to engage with a liner 926 positioned on the surface 924 and at least partially separate the liner 926 from the surface 924 of the on-skin wearable medical device when at least partially withdrawn from the surface 924 of the on-skin wearable medical device. In an embodiment, the liner removal component may include a body configured to extend axially within the internal cavity 903, and the body may be utilized to engage with the liner 926 positioned on the surface 924 and at least partially separate the liner 926 from the surface 924 of the on-skin wearable medical device when at least partially withdrawn from the surface 924 of the on-skin wearable medical device.

[0150] The liner removal component 928 may include at least a portion configured to extend into the internal cavity 903. The liner removal component 928 may, for example, extend axially within the internal cavity 903. The liner removal component 928 may include a first portion 930 that may be configured to engage the liner and a second portion 932 that is spaced apart from the first portion 930. The second portion 932 may be axially spaced apart from the first portion 930. The axial extent of the liner removal component 928 may provide various advantages. For example, a user attempting to grasp the liner removal component 928 to at least partially separate the liner 926 may be less likely to insert their fingers too far into the internal cavity 903 to at least partially separate the liner 926 from the surface 924. Such a feature may improve the ease with which a user can remove the liner 926. Additionally, the user may be less likely to come into contact with the tip (e.g., needle) of the insertion element 915 and potentially injure the user or detach the insertion element 915 or the transcutaneous analyte sensor from each other. Additionally, the user may be less likely to inadvertently detach the on-skin sensor assembly 508 from the housing 902.

[0151] FIG. 26B illustrates a perspective view of the liner removal component 928 separated from the internal cavity 903. A first portion 930 of the liner removal component 928 may comprise a cover for a portion of the liner 926 (marked in FIG. 26G) that covers the liner 926 on the surface 924 (marked in FIG. 26F). The cover can cover at least a portion of the surface 924. The first portion 930 of the liner removal component 928 may comprise a support for the liner 926 that supports the liner 926 on the surface 924 until the desired time for separating the liner 926 from the surface 924. The first portion 930 may comprise a substrate for the liner 926 positioned thereon and may have a flat shape as shown in FIG. 26B or another desired shape. In embodiments, the support provided by the liner removal component 928 can reduce the likelihood that vibration or shock (from a dispensing or dropping event) will dislodge the on-skin wearable medical device from the applicator housing 902 or the transcutaneous analyte sensor from the insertion element 915. Other benefits may result from the support provided by the liner removal component 928 in embodiments.

[0152] In embodiments, first portion 930 may engage liner 926 utilizing one or more bonding surfaces 934 (marked in FIGS. 26B and 26D ). In embodiments, bonding surface 934 may include an adhesive surface that bonds liner 926 to first portion 930. The adhesive surface may include, for example, a pressure-sensitive adhesive, or any other form of adhesive desired. Bonding surface 934 may have a variety of configurations. For example, FIG. 26B illustrates an annular shape for bonding surface 934. In embodiments, other configurations for bonding surface 934 may be utilized as desired.

[0153] In embodiments, first portion 930 may include an opening 937 for passage of insertion element 915 and the transcutaneous analyte sensor (as shown in FIG. 26A ). In embodiments, first portion 930 may include a sheath 939 configured to cover insertion element 915, particularly the tip of insertion element 915. Thus, when a user grasps liner removal component 928, the likelihood of contact with insertion element 915 and the transcutaneous analyte sensor results is reduced.

[0154] The intermediate portion 936 may be positioned between the first portion 930 and the second portion 932 and may provide height between the first portion 930 and the second portion 932. The intermediate portion 936 may comprise the spacer body in embodiments, or may have another form as desired. As shown in Figures 26A and 26B, the intermediate portion 936 may have a cylindrical shape, although other configurations may be utilized in embodiments as desired.

[0155] The intermediate portion 936 may include one or more guides 938, which, in embodiments, may extend along a channel 941 (marked in FIG. 26F ) in the interior surface of the applicator housing 902, which may prevent rotation of the liner removal component 928 before or during removal from the housing 902. The guides 938 may extend axially along the interior cavity 903 to orient the liner removal component 928 within the interior cavity 903. The guides 938 may prevent rotation of the first portion 930 to reduce the possibility of shearing the liner. Shearing of the liner may, for example, in embodiments, cause the surface 924 to undesirably fold or crease upon itself. In embodiments, the guides 938 may reduce the possibility of rotation of the liner removal component 928.

[0156] The second portion 932, in embodiments, may comprise a base for the liner removal component 928. In embodiments, the second portion 932 may be configured to be positioned in the opening 905 of the applicator housing 902. Thus, the likelihood of a user extending their fingers deep into the interior cavity 903 and potentially contacting or damaging the insertion element 915 or the transcutaneous analyte sensor may be reduced. The second portion 932, in embodiments, may include a gripping portion 940 positioned on the second portion 932 and configured to be gripped by a user to withdraw the liner removal component 928 from the surface 924 of the on-skin sensor assembly 508.

[0157] The gripping portion 940 may comprise a portion of the liner removal component 928, for example, for manual gripping or for removal via another method from the housing 902. The gripping portion 940, as shown in FIG. 26B, may comprise one or more flanges that may be configured for gripping.

[0158] The second portion 932 may include one or more flanges 933 extending radially outward from the intermediate portion 936. The flanges 933 may be configured to abut a distal end portion of the inner housing 906 to prevent proximal movement of the liner removal component 928.

[0159] In embodiments, the liner removal component 928 may have other configurations than those shown in Figures 26A-26G.

[0160] The liner removal component 928 can have at least a portion configured to extend into the internal cavity 903. In embodiments, the liner removal component 928 may comprise an insert into the internal cavity 903 that can be covered by the retainer 942 of the system. The liner removal component 928 may cover the internal cavity 903. The liner removal component 928 may comprise a cap that is covered by the retainer 942 of the system. For example, FIG. 26C illustrates a perspective view of the retainer 942 including a gripping portion 944 on an outer surface of the retainer 942 and an engagement portion 946 on an inner surface of the retainer 942. The retainer 942 may include a central portion 948 that comprises a cover that covers the liner removal component 928 when the retainer 942 is positioned over the liner removal component 928. The retainer 942 may comprise an outer lid for the applicator 900 during shipping and unpackaging of the applicator 900.

[0161] A central portion 948 of the retainer 942 may include one or more openings 950 that may allow a sterilizing substance, such as a sterilizing gas, to pass through to sterilize the internal components of the applicator 900. The central portion 948 may include a central support 952 that may be configured to compress the liner removal component 928 to hold the liner removal component 928 in place. The central support 952 may be configured to rotate against a distal surface of the first portion 930 of the liner removal component 928, allowing the retainer 942 to rotate relative to the liner removal component 928. In embodiments, the central portion 948 can compress the second portion 932 of the liner removal component 928 to hold the liner removal component 928 in place. The gripping portion 944 may be positioned radially outward of the central portion 948 and may be positioned on the second portion 932 of the liner removal component 928 when the retainer 942 is engaged with the housing 902. Engagement portion 946 may include threads or another form of engagement portion 946 for engaging a corresponding engagement portion 954 (as shown in FIG. 26A ) on the exterior surface of housing 902. Engagement portion 946 may be positioned on second portion 932 of liner removal component 928 and configured to engage engagement portion 954 to hold liner removal component 928 relative to applicator housing 902. Engagement portion 946 may be configured to be rotated relative to applicator housing 902 to release liner removal component 928 from applicator housing 902. Both engagement portions 946, 954 may be positioned on second portion 932 of liner removal component 928, in embodiments.

[0162] 26D illustrates a schematic cross-sectional view of the placement of liner 926 relative to first portion 930. Bonding surface 934 may be positioned proximate opening 937 in first portion 930 and openings in liner 926 and patch 922 to bond liner 926 to first portion 930.

[0163] 26A and 26C can separate from the housing 902. For example, the retainer 942 can be rotated relative to the housing 902, and the engagement portion 946 rotates relative to the housing 902 to release the retainer 942 from the housing and release the liner removal component 928 from the housing 902. FIG. 26E, for example, illustrates the retainer 942 separated from the housing 902, with the second portion 932 of the liner removal component 928 exposed.

[0164] A user may thus grasp the liner removal component 928, for example, by the gripping portion 940, and pull the liner removal component 928 from the surface 924 of the on-skin wearable medical device. The liner removal component 928 may be pulled axially from the internal cavity 903 of the housing 902. Figure 26F illustrates the resulting configuration of the applicator 900 in which the surface 924 is exposed and can be placed on the skin in the manner disclosed herein.

[0165] FIG. 26G illustrates the liner 926 coupled to the liner removal component 928 as it is being withdrawn from the housing 902 .

[0166] In embodiments, the liner removal component 928 may be configured to be reinserted into the internal cavity 903 after placement of the wearable medical device on the skin. The liner removal component 928 may, for example, be proximally inserted into the internal cavity 903, and the needle carrier assembly 910 may, for example, be pressed proximally to accommodate the liner removal component 928. The retainer 942 may be recoupled to the housing 902 over the liner removal component 928.

[0167] In embodiments, the retainer or liner removal component may have other fastening configurations to the applicator housing 902, for example, snaps, clamps, or other fastening configurations may be utilized as desired.

[0168] In embodiments, the liner removal component 928 may be flattened and may not extend axially into the internal cavity 903. For example, in embodiments in which the surface 924 of the on-skin sensor assembly 508 is not positioned within an internal cavity, the liner removal component 928 may not need to extend into such a cavity. The liner removal component 928 may still remain available for access and grasping by a user, if desired. In embodiments, other forms of liner removal components configured to extend axially within the internal cavity 903 may be utilized. For example, a pull ring or other form of axially extending tether may be utilized to at least partially separate the liner from the surface 924.

[0169] 27A-27C illustrate one embodiment of a liner removal component 1000 configured similarly to the liner removal component 928 shown in FIGS. 26A-26G, but including a textured gripping portion 1002. The liner removal component 1000 can include a first portion 1004, a second portion 1006, and a middle portion 1008, each configured similarly to the respective first portion 930, second portion 932, and middle portion 936 of the liner removal component 928. The first portion 1004 may include a sheath 1010 including multiple openings for exposing the insertion element 915 to any sterilizing substance, such as a sterilizing gas, that may be utilized.

[0170] Figure 27B illustrates a top perspective view of the liner removal component 1000 withdrawn from the housing 902. A liner, not shown in Figure 27B, will be present on the first portion 1004 once the liner removal component 1000 is removed from the applicator housing 902. Figure 27C illustrates a bottom perspective view of the liner removal component 1000 withdrawn from the housing 902.

[0171] 28A-28E illustrate one embodiment of a liner removal component 1050 configured similarly to the liner removal component 928 shown in FIGS. 26A-26G but including a spring 1052. The spring 1052 may be configured to bias against the on-skin wearable medical device, moving the liner removal component 1050 away from the on-skin wearable medical device and at least partially separating the liner 926 from the surface 924. The liner removal component 1050 may include a second portion 1054 and an intermediate portion 1056, each configured similarly to the respective second portion 932 and intermediate portion 936 of the liner removal component 928. The first portion 1058 of the liner removal component 1050 may include the spring 1052 and may include a sheath 1060 including multiple openings for exposing the insertion element 915 to any sterilizing substance, such as a sterilizing gas, that may be utilized.

[0172] Figure 28A illustrates a top perspective view of the liner removal component 1050 withdrawn from the housing 902. The liner, not shown in Figure 28A, will be present on the first portion 1058 when the liner removal component 1050 is removed from the applicator housing 902. Figure 28B illustrates a bottom perspective view of the liner removal component 1050 withdrawn from the housing 902. Figure 28C illustrates a side view of the liner removal component 1050.

[0173] 28A-28C, a spring 1052 may protrude proximally from a proximal bearing surface 1062 of the liner removal component 1050. The spring 1052 may be biased to protrude from the proximal bearing surface 1062, as shown in FIG. 28C, and may provide a resilient force when pushed distally. The spring 1052 may, in embodiments, comprise a leaf spring as shown in FIGS. 28A-28C, or may have another configuration.

[0174] The spring 1052 may be positioned such that it exerts an asymmetric force on the on-skin wearable medical device. Referring to FIG. 28A , the spring 1052 may be positioned to exert a force on only a portion of the on-skin wearable medical device, such that liner pull-out occurs proximate that portion. The spring 1052 may be positioned, for example, adjacent to and to one side of the opening 1064 of the liner removal component 1050. Such a position can exert an asymmetric force on the on-skin wearable medical device.

[0175] 28D illustrates a cross-sectional view of the liner removal component 1050, along with a schematic diagram of the bonding surface 934, liner 926, patch 922, and on-skin sensor assembly 508 positioned on a first portion 1058 of the liner removal component 1050. In the configuration shown in FIG. 28D, the liner removal component 1050 may be inserted into the interior cavity 903 of the applicator housing 902, for example, in the configuration shown in FIG. 26A. A retainer 942 (as shown in FIG. 26C) may be utilized to press the liner removal component 1050 against the on-skin sensor assembly 508, compressing the spring 1052 and moving the spring 1052 to the lowered or distal position shown in FIG. 28D.

[0176] 28D during storage and transportation of the system, as well as during sterilization and other processes that may be applied to the system. The liner 926 may remain in contact with or cover the surface 924 of the patch 922. The spring 1052 may bias against the on-skin sensor assembly 508, which in embodiments may comprise the housing of the on-skin sensor assembly 508 and / or the patch 922.

[0177] The spring 1052 may be positioned such that one or more of the coupling surfaces 934 are positioned between the spring 1052 and the opening 1064. For example, the coupling surface 934 may be positioned radially outward of the opening 1064 and between the spring 1052 and the opening 1064. In embodiments, the spring 1052 may be positioned to apply a force that is radially offset from the center of the liner removal component 1050, such that a torque may be applied to the liner removal component 1050 by the force of the spring 1052. In embodiments, other positions for the spring 1052 may be utilized.

[0178] 28D until the desired time to remove the retainer 942 from the applicator housing 902 for placement of the on-skin wearable medical device on the skin. Upon removal of the retainer 942, the spring 1052 may apply a force to the on-skin wearable medical device, causing the liner removal component 1050 to move away from the on-skin wearable medical device and at least partially separate the liner 926 from the surface 924.

[0179] FIG. 28E, for example, illustrates the spring 1052 exerting a force on the on-skin wearable medical device. The spring 1052 has been moved to a raised or proximal position, causing the liner removal component 1050 to move away from the on-skin wearable medical device. The movement may be axial, or may include rotational movement (as indicated by arrow 1066 shown in FIG. 28E) or a combination of axial and rotational movement. The movement may at least partially separate the liner 926 from the surface 924. The removal may be of adjacent ones of the bonding surfaces 924, as shown by the gap 1068 between the liner 926 and the surface 934 in FIG. 28E. In embodiments, the spring 1052 may remove larger or smaller portions of the liner 926, as desired.

[0180] In embodiments, the spring 1052 may initiate removal of the liner 926, thereby reducing the force required by a user to remove the entire liner 926. For example, the gap 1068 formed between the liner 926 and the surface 924 may contain a first portion of the liner 926 that is removed, with the remaining portion being removed by the user as the liner removal component 1050 is axially withdrawn from the surface 924. Such reduced force can beneficially reduce the likelihood that a user will inadvertently apply too much force to the liner removal component 1050 and liner 926 when removing the liner removal component 1050, which may undesirably disengage the on-skin sensor assembly 508 from the applicator housing 902 prior to deployment.

[0181] 28E , removal of the liner 926 from the surface 924 may be asymmetric, which may further enable peeling of the liner 926. Because the liner removal component 1050 is withdrawn axially from the surface 924, in embodiments, the peeling may be horizontal to the surface 924. Such a peeling motion of the liner 926 may reduce the force required by a user to remove the entire liner 926. The liner removal component 1050 may therefore be configured to asymmetrically separate the liner 926 from the surface 924 as the liner removal component 1050 is at least partially withdrawn from the surface 924. The liner removal component 1050 may be configured to peel the liner 926 from the surface 924 as the liner removal component 1050 is at least partially withdrawn from the surface 924.

[0182] A spring may be utilized with any embodiment of the component for at least partially removing a liner disclosed herein.

[0183] 29A-29D illustrate one embodiment of the liner removal component 1100 configured to be rotated relative to the applicator housing 902 to release the liner removal component 1100 from the applicator housing 902. The liner removal component 1100 may include a first portion 1102, a second portion 1104, and an intermediate portion 1106. The second portion 1104 may be spaced apart from the first portion 1102.

[0184] The first portion 1102 may be configured similarly to the first portion 930 of the liner removal component 928 and may be configured to engage the liner 926. The first portion 1102 may cover at least a portion of the liner 926 and may support the liner 926. The first portion 1102 may include a cavity 1108, which may be sized to allow the first portion 1102 to rotate relative to the insert element 915 and not contact the insert element 915. Such a configuration may reduce the likelihood that the first portion 1102 will displace or otherwise damage the insert element 915. The cavity 1108 may extend distally from a proximal opening 1110 (marked in FIG. 29B ) of the first portion 1102. The cavity 1108 may form a well for receiving the insert element 915. The first portion 1102 may include one or more openings 1112 for exposing the insert element 915 to any sterilizing substance, such as a sterilizing gas, that may be utilized.

[0185] The first portion 1102 may include a ring 1114 (marked in FIG. 29B ), which may have a flat surface, around the cavity 1108. The ring 1114 may comprise a portion of the first portion 1102 that engages with the liner 926 to remove the liner 926 when the liner removal component 1100 is withdrawn from the housing 902. The ring 1114 may contact the periphery of the liner 926 to support the liner 926 and to support the on-skin sensor assembly 508 within the applicator housing 902. Such support may improve retention of the liner 926 on the patch 922 and may provide robustness of the on-skin sensor assembly 508 against drops and other impacts that may be applied to the on-skin sensor assembly 508 within the applicator housing 902.

[0186] The intermediate portion 1106 may extend axially between the first portion 1102 and the second portion 1104 and may have a cylindrical shape as shown in FIG. 29A. The intermediate portion 1106 may comprise a spacer body in embodiments or may have another form as desired. The intermediate portion 1106 may be configured to transfer rotation of the second portion 1104 to the first portion 1102 to enable the first portion 1102 to withdraw the liner 926 from the on-skin sensor assembly 508.

[0187] The second portion 1104 may be configured to be positioned in the opening 905 of the housing 902 and may include a gripping portion 1116 positioned on the second portion 1104. The second portion 1104 may comprise a base for the liner removal component 1100. The gripping portion 1116 may be configured to be gripped to pull the liner removal component 1100 from the surface 924 of the on-skin wearable medical device. The gripping portion 1116 can be positioned on an outer surface of the second portion 1104 positioned on the outer surface of the housing 902. In an embodiment, the second portion 1104 may be configured to extend over the outer surface of the applicator housing 902. The second portion 1104 may further include an engagement portion 1118 positioned on the second portion 1104 and configured to engage a portion of the housing 902 to hold the liner removal component 1100 relative to the housing 902. The engagement portion 1118 may include threads, for example in the form of threads, that engage with an engagement portion on the housing.

[0188] The engagement portion 1118 may be configured to be rotated relative to the housing 902 to release the liner removal component 1100 from the housing 902 .

[0189] 29C , when the engagement portion 1118 is rotated, the entire liner removal component 1100 rotates, causing the liner removal component 1100 to move axially and be pulled out of the housing 902, and at least partially separate the liner (not shown in FIG. 29C ) from the surface 924 of the on-skin sensor assembly 508. The second portion 1104 may separate from the applicator housing 902. The second portion 1104 may be configured to unthread from the applicator housing 902 to at least partially separate the liner removal component 1100 from the applicator housing 902.

[0190] Thus, the first portion 1102 can be rotated and withdrawn axially from the surface 924 of the on-skin sensor assembly 508 to withdraw the liner from the surface 924 of the on-skin sensor assembly 508. The liner removal component 1100 may comprise a base for the applicator housing 902 and may cover the internal cavity 903. The liner removal component 1100, in an embodiment, may comprise a cap.

[0191] In embodiments, the liner removal component 1100 may be configured to be reinserted into the internal cavity 903 after placement of the wearable medical device on the skin. The liner removal component 1100 may be positioned, for example, as shown in FIG. 29D and rotated back onto the housing 902 to reconnect to the housing.

[0192] 29A-29D may be configured to rotate and at least partially separate from the surface 924 of the on-skin sensor assembly 508. For example, FIG. 29E illustrates such an embodiment of a liner 1113 including a cutout portion 1115 having a curved or spiral shape that allows the liner to rotate relative to the transcutaneous analyte sensor 1117 without contacting the sensor 1117. The liner 1113 may include multiple layers 1119 that may be folded over one another with a central opening 1121 between the layers 1119. Layer 1119a (marked in FIG. 29F) may include a first portion 1123a and a second portion 1123b, forming multiple layers, with the first portion 1123a folded over the second portion 1123b. The layers 1119 may be arranged in a butterfly configuration. Attachment portions 1120 in the form of multiple longitudinal strips may extend along the folded portion of the liner 1113. The attachment portions 1120 may be arranged to allow the folded portion of the liner 1113 to rotate open as the liner removal component 1100 extends axially away from the surface 1122 of the patch to engage the skin (marked in FIG. 29F).

[0193] FIG. 29F illustrates a schematic cross-sectional view of the folded liner shown in FIG. 29E.

[0194] 30A-30E illustrate one embodiment of the liner removal component 1200 configured to be rotated relative to the housing 902 to release the liner removal component 1200 from the housing 902. The liner removal component 1200 may include a first portion 1202 configured to rotate relative to a second portion 1204 to enable the liner removal component 1200 to be axially withdrawn from the surface 924 of the on-skin sensor assembly 508. The first portion 1202 may be axially spaced from the second portion 1204.

[0195] First portion 1202 may be configured similarly to first portion 930 of liner removal component 928 and may be configured to engage liner 926. First portion 1202 may cover at least a portion of and support liner 926. First portion 1202 may include a sheath 1206 configured to receive insertion element 915 and reduce the likelihood of contact with insertion element 915. First portion 1202 may be configured to slide axially within internal cavity 903 but not rotate within internal cavity 903.

[0196] For example, the intermediate portion 1208 in embodiments may include one or more guides 1210 (marked in FIG. 30B ) that may extend along a channel 1212 (marked in FIG. 30E ). The one or more guides 1210 may be configured to engage an inner surface of the applicator housing 902 to prevent rotation of the first portion 1202 relative to the applicator housing 902. The channel 1212 in the inner surface of the housing 902 can prevent the first portion 1202 of the liner removal component 1200 from rotating before or during removal from the housing 902. The guides 1210 can extend axially along the internal cavity 903 to orient the liner removal component 1200 within the internal cavity 903. The guides 1210 may be configured to prevent the first portion 1202 from rotating relative to the applicator housing 902 as the second portion 1204 rotates relative to the first portion 1202. The second portion 1204 may also rotate relative to the applicator housing 902. Preventing rotation can prevent the liner from rotating as it peels off the surface of the on-skin assembly. In embodiments, the guide 1210 may be configured to reduce rotation of the first portion 1202 relative to the applicator housing 902.

[0197] 30A and 30B , the intermediate portion 1208 in embodiments may include one or more rotational couplers 1214 that may allow the first portion 1202 to rotate relative to the second portion 1204 while the first portion 1202 maintains its rotational position relative to the housing 902. The intermediate portion 1208 in embodiments may comprise a non-rotating portion of the liner removal component 1200. The rotational couplers 1214 in embodiments may be configured to engage one or more bearing surfaces 1216 of the second portion 1204 of the liner removal component 1200. The rotational couplers 1214 can have any desired configuration. The rotational couplers 1214 may, for example, comprise arms 1215 that engage one or more bearing surfaces 1216 of the second portion 1204. The rotation couplers 1214 may each include a bearing surface configured to engage one or more bearing surfaces 1216 of the second portion 1204 to couple the first portion to the second portion and allow rotation of the first portion 1202 relative to the second portion 1204. The rotation couplers 1214 may be configured to rotate relative to the one or more bearing surfaces 1216.

[0198] 30A , the one or more rotary couplers 1214 may be initially spaced apart from the one or more bearing surfaces 1216 of the second portion 1204 with a gap 1217. Rotation of the first portion 1202 relative to the second portion 1204 may reduce the size of the gap 1217, allowing the one or more rotary couplers 1214 to contact the one or more bearing surfaces 1216. Rotation of the first portion 1202 relative to the second portion 1204 may bring the one or more rotary couplers 1214 into contact with the one or more bearing surfaces 1216. The arms 1215 may engage the one or more bearing surfaces 1216, allowing the second portion 1204 to pull the first portion 1202 axially and withdraw the first portion 1202 from the internal cavity 903.

[0199] In embodiments, the heights of the rotary couplers may be different from one another so that a first of the rotary couplers is configured to contact the receiving portion before a second of the rotary couplers. For example, the lengths of the rotary couplers 1214 may be different from one another to create a desired asymmetric tension force on the liner 926. In embodiments, at least two rotary couplers may be provided. In embodiments, at least three rotary couplers may be provided. In embodiments, a greater number of rotary couplers may be provided if desired.

[0200] The first rotary coupler 1214a may have a shorter length than the second rotary coupler 1214b, allowing the first rotary coupler 1214a to engage and be pulled axially earlier than the second rotary coupler 1214b. Thus, the first portion 1202 may be angled as it is pulled from the on-skin wearable medical device and may create an asymmetric force on the liner 926 during release. The initial pulling force on the liner 926 may be to one side of the liner 926 and therefore may exert an asymmetric force on the liner 926. The liner removal component 1200 may be configured to asymmetrically separate the liner 926 from the surface of the on-skin wearable medical device as the liner removal component 1200 is at least partially pulled from the surface. The liner removal component 1200 may be coupled to the liner 926 such that when a user twists or otherwise removes the second portion 1204 from the applicator housing 902, the liner removal component 1200 pulls the liner 926 away from the surface 924. The asymmetric force can result in the liner 926 peeling away, which can reduce the removal force. Because the liner removal component 1200 is pulled axially from the surface 924, in embodiments, the peeling of the liner 926 may be horizontal to the surface 924.

[0201] The second portion 1204 may be configured to be positioned in the opening 905 of the housing 902 and may include a gripping portion 1218 positioned on the second portion 1204. The second portion 1204 may comprise a base for the liner removal component 1200. The gripping portion 1218 may be configured to be gripped to pull the liner removal component 1200 from the surface 924 of the on-skin wearable medical device. The gripping portion 1218 can be positioned on an outer surface of the second portion 1204 positioned on the outer surface of the housing 902. The second portion 1204 may be configured to extend over the outer surface of the applicator housing 902. The second portion 1204 may further include an engagement portion 1220 positioned on the second portion 1204 and configured to engage a portion of the housing 902 to hold the liner removal component 1200 relative to the housing 902. The engagement portion 1220 may include threads, for example in the form of threads, that engage with the engagement portion 954 on the housing.

[0202] A central portion of the second section 1204 can include one or more bearing surfaces 1216 that engage arms 1215 of one or more rotary couplers 1214 .

[0203] FIG. 30C illustrates a cross-sectional view of the liner removal component 1200.

[0204] In operation, the second portion 1204 can be grasped and rotated to rotate the engagement portion 1220 relative to the housing 902. Rotation of the second portion 1204 can slide the second portion 1204 axially distally relative to the housing 902, causing one or more bearing surfaces 1216 of the second portion 1204 to engage the arms 1215 of the one or more rotary couplers 1214. FIG. 30D , for example, illustrates such a configuration. The second portion 1204 can be unscrewed from the applicator housing 902 to at least partially separate the liner removal component 1200 from the applicator housing 902. As shown, the distance between the one or more bearing surfaces 1216 and the arms is reduced. In embodiments, rotary coupler 1214a can engage before rotary coupler 1214b, creating an asymmetric force on the liner 926. The second portion 1204 may continue to be rotated to axially withdraw the first portion 1202 from the surface 924 of the on-skin sensor assembly 508 .

[0205] The configuration of the rotational coupler 1214 allows the second portion 1204 to rotate freely, but only applies axial motion to the first portion 1202 to pull the first portion 1202 axially without rotation of the first portion 1202 relative to the housing 902. For example, the guide 1210 shown in FIG. 30B further prevents and / or reduces the possibility of rotation of the first portion 1202 relative to the housing 902.

[0206] The second portion 1204 of the liner removal component 1200 may continue to be rotated until the liner removal component 1200 disengages from the housing 902, and the liner removal component 1200 may be withdrawn from the interior cavity 903. The liner 926 may be withdrawn from the surface 924 of the on-skin sensor assembly 508. Figure 30E illustrates the resulting configuration in which the surface 924 of the on-skin sensor assembly 508 is exposed for placement on the skin.

[0207] The liner removal component 1200 may comprise a base for the applicator housing 902. The liner removal component 1200 may cover the interior cavity 903. The liner removal component 1200 may, in embodiments, comprise a cap.

[0208] In embodiments, the liner removal component 1200 may be configured to be reinserted into the internal cavity 903 after placement of the wearable medical device on the skin. The liner removal component 1200 may be rotated back onto the housing 902 to reconnect to the housing, for example.

[0209] In embodiments, during assembly, the second portion 1204 of the liner removal component 1200 may be placed into the bottom of the applicator housing 902 after the first portion 1202 and the middle portion 1208 are inserted into the internal cavity 903 through the bottom of the applicator housing 902. The one or more bearing surfaces 1216 may be configured to snap onto the ends of the arms 1215 when the second portion 1204 is placed or screwed onto the bottom of the applicator housing 902. The ends of the arms 1215 may be configured to flex on the one or more bearing surfaces 1216 during assembly. At least a portion of the liner removal component 1200 may be configured to be assembled with the one or more arms 1215 flexed by the second portion 1204.

[0210] FIG. 30F illustrates a cross-sectional view of a liner removal component 1250 configured similarly to the liner removal component 1200 shown in FIGS. 30A-30D, but including a first portion 1252 with a larger surface area. The first portion 1252 may be configured to cover at least a portion of the liner 926, may support the liner 926, or may comprise a substrate upon which the liner 926 is positioned. The first portion 1252 may have a flat shape, as shown in FIG. 30F. The flat shape may provide a flat surface for securely adhering the liner 926 to the first portion 1252. The first portion 1252 may include an opening 1253 for the insertion element 915 and the transcutaneous analyte sensor to pass through.

[0211] The one or more rotary couplers 1254 may be configured similarly to the rotary coupler 1214 shown in FIGS. 30A-30D. The rotary coupler 1254 can allow the first portion 1252 to rotate relative to the second portion 1256 while the first portion 1252 maintains its rotational position relative to the housing 902. The second portion 1256 may be configured similarly to the second portion 1204 shown in FIGS. 30A-30D. An annular gap 1262 is shown between the first portion 1252 and the second portion 1256. The intermediate portion 1258 may include one or more guides 1260 configured similarly to the guide 1210 shown in FIG. 30B. The liner removal component 1250 may operate in a manner similar to the liner removal component 1200 shown in FIGS. 30A-30D. The liner removal component 1250 may be utilized with the systems and applicator housings disclosed herein.

[0212] Figure 30G illustrates a perspective view of the liner removal component 1250. Figure 30H illustrates a top perspective view of the liner removal component 1250.

[0213] 31A-31H illustrate one embodiment of the liner removal component 1300 configured to be rotated relative to the housing 902 to release the liner removal component 1300 from the housing 902. The liner removal component 1300 may include a first portion 1302 configured to rotate relative to a second portion 1304 to allow the liner removal component 1300 to be axially withdrawn from the surface 924 of the on-skin sensor assembly 508. The first portion 1302 may be axially spaced from the second portion 1304.

[0214] The height of the first portion 1302 relative to the second portion 1304 is configured to be adjustable. The liner removal component 1300 may include a cam surface 1306 (marked in FIG. 31B ) configured to adjust the height of the first portion 1302 relative to the second portion 1304.

[0215] First portion 1302 may be configured similarly to first portion 930 of liner removal component 928 and may be configured to engage liner 926. First portion 1302 may cover at least a portion of liner 926 and may support liner 926. First portion 1302 may include a sheath 1308 configured to receive insertion element 915 and reduce the likelihood of contact with insertion element 915. First portion 1302 may be configured to slide axially within internal cavity 903 but not rotate within internal cavity 903.

[0216] For example, the intermediate portion 1310 in embodiments may include one or more guides 1312 (marked in FIG. 31B ), which may extend along a channel in the inner surface of the housing 902, which can prevent and / or reduce the possibility of rotation of the first portion 1302 of the liner removal component 1300 before or during removal from the housing 902. The guides 1312 may be configured to engage the inner surface of the housing 902. The guides 1312 may be in the form of arms extending radially outward from the intermediate portion 1310 in embodiments, or may have another configuration. The guides 1312 can orient the liner removal component 1300 within the internal cavity 903. The guides 1312 may prevent and / or reduce the possibility of rotation of the first portion 1302 relative to the applicator housing 902 as the second portion 1304 rotates relative to the first portion 1302, which can reduce the possibility of shearing the liner. The second portion 1304 may also rotate relative to the applicator housing 902 .

[0217] 31B-31H, in embodiments, the intermediate portion 1310 may have a rotary coupler including a cam surface 1306 that can be configured to adjust the height of the first portion 1302 relative to the second portion 1304. The cam surface 1306, in embodiments, may extend circumferentially around the outer surface of the intermediate portion 1310 or may comprise a surface that extends axially as the cam surface 1306 extends circumferentially. Thus, the cam surface 1306 extends at an angle (e.g., as shown in FIG. 31D) that causes axial movement of the first portion 1302 due to rotational movement of the second portion 1304. Thus, the angle of the cam surface 1306 can dictate the rate at which the first portion 1302 moves axially due to rotational movement of the second portion 1304.

[0218] For example, FIG. 31D illustrates a view of a rotary coupler showing an arm 1313 extending into a channel that includes a cam surface 1306. A central portion of the second portion 1304 may include one or more arms 1313 that engage the cam surface 1306. FIG. 31E illustrates that the first portion 1302 can be at a height relative to the second portion 1304. FIG. 31F illustrates that upon rotation of the second portion 1304, the arm 1313 can slide along the cam surface 1306, thus sliding the first portion 1302 axially distally. The guide 1312 can assist the first portion 1302 in producing only axial movement in response to rotational movement of the second portion 1304. FIG. 31C illustrates the resulting variation in the height of the first portion 1302 relative to the second portion 1304.

[0219] 31G and 31H, the cam surface 1306 may be configured such that axial movement occurs only upon rotation of the second portion 1304 relative to the intermediate portion 1310 in one direction. For example, as shown in FIG. 31G, when the second portion 1304 rotates left, the arm 1313 extends over the cam surface 1306, resulting in axial movement. When the second portion 1304 rotates right in FIG. 31G, no axial movement occurs; rather, the arm 1313 transitions to another cam surface, as represented by the path of the arrow in FIG. 31H. The cam surface 1306 may provide features to prevent and / or reduce undesired axial movement of the first portion 1302, as shown in FIG. 31E, such as toward the on-skin wearable medical device.

[0220] 31A , the second portion 1304 may be configured to be positioned in the opening 905 of the housing 902 and may include a gripping portion 1314 positioned on the second portion 1304. The gripping portion 1314 may be configured to be gripped to pull the liner removal component 1300 from the surface 924 of the on-skin wearable medical device. The gripping portion 1314 can be positioned on an outer surface of the second portion 1304 positioned on the outer surface of the housing 902. The second portion 1304 may be configured to extend over the outer surface of the applicator housing 902. The second portion 1304 may further include an engagement portion 1316 positioned on the second portion 1304 and configured to engage a portion of the housing 902 to hold the liner removal component 1300 relative to the housing 902. The engagement portion 1316 can include threads, for example, in the form of threads, that engage with an engagement portion on the housing. The liner removal component 1300 may comprise a base for the applicator housing 902. The liner removal component 1300 may cover the interior cavity 903. The liner removal component 1300 may, in embodiments, comprise a cap.

[0221] In operation, the second portion 1304 can be grasped and rotated to rotate the engagement portion 1316 relative to the housing 902. Rotation of the second portion 1304 causes the second portion 1304 to slide axially distally relative to the housing 902, causing the cam surface 1306 to slide the first portion 1302 axially. Continued rotation of the second portion 1304 may cause the first portion 1302 to be pulled axially from the surface 924 of the on-skin sensor assembly 508. The second portion 1304 may be unscrewed from the applicator housing 902 to at least partially separate the liner removal component 1300 from the applicator housing 902.

[0222] The configuration of cam surface 1306 allows second portion 1304 to rotate and pull first portion 1302 axially without first portion 1302 rotating relative to housing 902. For example, guide 1312 shown in FIG. 31B prevents and / or reduces the possibility of rotation of first portion 1302 relative to housing 902.

[0223] The second portion 1304 of the liner removal component 1300 may continue to be rotated until the liner removal component 1300 disengages from the housing 902, and the liner removal component 1300 may be withdrawn from the interior cavity 903. The liner 926 may be withdrawn from the surface 924 of the on-skin sensor assembly 508.

[0224] In embodiments, the liner removal component 1300 may be configured to be reinserted into the internal cavity 903 after placement of the wearable medical device on the skin. The liner removal component 1300 may be rotated back on the applicator housing 902 to recouple to the housing. Referring to FIG. 31C , the intermediate portion 1310 has axially slid relative to the second portion 1304 and is positioned within the cavity of the second portion 1304. The intermediate portion 1310 fits within the cavity of the second portion 1304 and slides telescopically within the cavity. The liner removal component 1300 is configured to collapse. The intermediate portion 1310 collapses into the second portion 1304. The reduced height of the first portion 1302 may allow the liner removal component 1300 to be recoupled to the applicator housing 902 after placement of the wearable medical device on the skin.

[0225] 32A-32C illustrate one embodiment of a liner removal component 1350 in which the intermediate portion 1352 can slide axially relative to the second portion 1354 when the lock 1356 is released. The first portion 1358 can be configured similarly to, for example, the first portion 1302 of the liner removal component 1300 shown in FIG. 31B. The intermediate portion 1352 can include a guide (not shown) similar to the guide 1312 shown in FIG. 31B that can prevent and / or reduce rotational movement of the intermediate portion 1352 and the first portion 1358 upon rotation of the second portion 1354. The first portion 1358 can be axially spaced from the second portion 1354.

[0226] Intermediate portion 1352 may be configured to slide axially relative to second portion 1354 and fit within cavity 1355 (marked in FIG. 32B ) of second portion 1354. Intermediate portion 1352 may be, for example, conical in shape and may fit within conical cavity 1355 of second portion 1354. In embodiments, intermediate portion 1352 may have different configurations as desired.

[0227] 32A and 32B, the intermediate portion 1352 can be held in a raised or proximal position relative to the second portion 1354 by a lock 1356. The lock 1356, as shown in FIGS. 32A and 32B, can comprise a pin or other structure for retaining the axial position of the intermediate portion 1352. The lock 1356 can include a deformable lock 1356 that breaks when the intermediate portion 1352 rotates relative to the second portion 1354. For example, when sufficient rotational force is applied to the lock 1356, the lock can break into two pieces 1356a and 1356b, as shown in FIG. 32C.

[0228] Second portion 1354 may include a cavity 1355 that may be molded into a shape to receive intermediate portion 1352. Intermediate portion 1352 may fit within cavity 1355 of second portion 1354 and may slide telescopically within cavity 1355. Intermediate portion 1352 may be collapsed into second portion 1354.

[0229] During operation, the intermediate portion 1352 can be held in the raised or proximal position shown in FIG. 32A by the lock 1356. The first portion 1358 can support the liner 926 on the engagement surface of the on-skin wearable medical device. When placing the on-skin wearable medical device, the user can rotate the second portion 1354 relative to the first portion 1358, thereby deforming the lock 1356. The first portion 1358 can be prevented from rotating with the second portion 1354 due to the presence of a guide (not shown) similar to the guide 1312 shown in FIG. 31B.

[0230] The lock 1356 may split into pieces 1356a and 1356b, allowing the middle portion 1352 to telescopically slide into the cavity 1355 of the second portion 1354. The liner removal component 1350 is configured to collapse. The middle portion 1352 collapses into the second portion 1354, as shown in FIG. 32C . The reduced height of the first portion 1358 may allow the liner removal component 1350 to be recoupled to the applicator housing 902 after placement of the wearable medical device on the skin.

[0231] 33A-33C illustrate one embodiment of a liner removal component 1400 configured to adjust the height of the first portion 1402 relative to the second portion 1404. The liner removal component 1400 may include one or more deflectable arms 1406 coupling the first portion 1402 to the second portion 1404. The deflectable arms 1406 are configured to deflect to allow the liner removal component 1400 to collapse, reducing the height of the liner removal component 1400 after use. The second portion 1404 is axially spaced from the first portion 1402.

[0232] First portion 1402 may be configured similarly to first portion 930 of liner removal component 928 and may be configured to engage liner 926. First portion 1402 may cover at least a portion of liner 926 and may support liner 926. First portion 1402 may include a sheath 1408 configured to receive insertion element 915 and reduce the likelihood of contact with insertion element 915. First portion 1402 may be configured to slide axially within internal cavity 903.

[0233] The second portion 1404 may be configured to be positioned in the opening 905 of the housing 902. The second portion 1404 may extend radially outward from the intermediate portion 1410 and overlap a distal end portion of the housing 902 to prevent and / or reduce the possibility of undesired proximal movement of the liner removal component 1400.

[0234] The retainer 1412 may be positioned on the second portion 1404 and may comprise a retaining ring that couples to the applicator housing 902 and the second portion 1404 of the liner removal component 1400. The retainer 1412 may be positioned on the second portion 1404 and include an engaging portion 1414 configured to engage a portion of the applicator housing 902 to hold the liner removal component 1400 relative to the housing 902. The retainer 1412 may be positioned on the second portion 1404 of the liner removal component 1400 and include a gripping portion 1416 configured to be gripped by a user to withdraw the liner removal component from the surface 924 of the on-skin sensor assembly 508. The ring shape of the retainer 1412 may form an opening 1418 through which the second portion 1404 can pass. The retainer 1412 in embodiments may be configured to rotate without causing rotation of the liner removal component 1400.

[0235] 33B, the intermediate portion 1410 of the liner removal component 1400 may include one or more deflectable arms 1406. The one or more deflectable arms 1406 may have a variety of configurations and, in an embodiment such as that shown in FIG. 33B, may be arranged in a spiral configuration. The deflectable arms 1406 may extend radially inward from the second portion 1404 and couple to the first portion 1402, although other configurations may be utilized in embodiments as desired.

[0236] In operation, the retainer 1412 may be removed and the second portion 1404 of the liner removal component 1400 may be pulled axially from the internal cavity 903 to pull the liner 926 from the surface 924 of the on-skin wearable medical device. The surface 924 of the on-skin wearable medical device may then be placed on the skin of a recipient in a manner as disclosed herein. The liner removal component 1400 may comprise a base for the applicator housing 902 and may cover the internal cavity 903. The liner removal component 1400, in an embodiment, may comprise a cap.

[0237] Referring to FIG. 33C , in embodiments, the needle carrier assembly 910 of the applicator 900 may remain locked in the distal position after deployment. Such a feature can protect the user from contact with the insertion element. Because of this, the size of the internal cavity 903 may be reduced, making it difficult to reattach the liner removal component according to certain embodiments herein. However, in embodiments such as those shown in FIGS. 33A-33B , the deflectable arm 1406 may flex to allow the height of the first portion 1402 to be adjusted relative to the second portion 1404. For example, FIG. 33C illustrates the deflectable arm 1406 flexed to allow the liner removal component 1400 to be reattached to the housing 902. The flexing can accommodate the liner removal component 1400 being coupled to the applicator housing 902. Thus, the liner removal component 1400 serves as a collapsible body configured to be collapsed to allow reattachment after use.

[0238] The liner removal component 1400 may, in embodiments, further comprise a unitary body that may be formed in a single mold if desired. Other configurations of the liner removal component 1400 may be utilized in embodiments.

[0239] 34A-34G illustrate one embodiment of a liner removal component 1500 configured such that the height of the first portion 1502 relative to the second portion 1504 is adjustable. The liner removal component 1500 may include one or more deflectable arms 1506 coupling the first portion 1502 to the second portion 1504. The deflectable arms 1506 are configured to deflect to allow the liner removal component 1500 to collapse, reducing the height of the liner removal component 1500. The first portion 1502 may be axially spaced from the second portion 1504.

[0240] In the embodiment of FIGS. 34A-34G, the height of the liner removal component 1500 may be adjusted to allow the liner 926 to be pulled from the surface 924 of the on-skin sensor assembly 508.

[0241] The first portion 1502 may be configured similarly to the first portion 930 of the liner removal component 928 and may be configured to engage the liner 926. The first portion 1502 may cover at least a portion of the liner 926 and may support the liner 926. The first portion 1502 may be configured to slide axially within the internal cavity 903. The first portion 1502 may include one or more guides 1508, which may be configured to extend along the channel 1510 of the housing 902, for example. The guides may be configured to engage an inner surface of the applicator housing 902 to prevent and / or reduce rotation of the first portion 1502 relative to the applicator housing 902. The guides 1508 may prevent and / or reduce the likelihood of the first portion 1502 rotating within the internal cavity 903. The guides 1508 may prevent and / or reduce the likelihood of rotation of the first portion 1502 to reduce the likelihood of shearing the liner.

[0242] The second portion 1504 may be configured to be positioned in the opening 905 of the housing 902. The second portion 1504 may extend radially outward from the intermediate portion 1520 and overlap a distal end portion of the housing 902 to prevent and / or reduce the possibility of undesired proximal movement of the liner removal component 1500.

[0243] The retainer 1512 may be positioned on the second portion 1504 and may comprise a retaining ring that couples to the housing 902 and the second portion 1504 of the liner removal component 1500. The retainer 1512 may be positioned on the second portion 1504 and include an engaging portion 1514 configured to engage a portion of the housing 902 to hold the liner removal component 1500 relative to the housing 902. The retainer 1512 may be positioned on the second portion 1504 of the liner removal component 1500 and include a gripping portion 1516 configured to be gripped by a user to pull the liner removal component from the surface 924 of the on-skin sensor assembly 508. The ring shape of the retainer 1512 may form an opening 1518 through which the second portion 1504 can pass. The retainer 1512 in embodiments may be configured to rotate without causing rotation of the liner removal component 1500.

[0244] 34B , the intermediate portion 1520 of the liner removal component 1500 may include one or more deflectable arms 1506. The one or more deflectable arms 1506 may have various configurations and, in an embodiment such as that shown in FIG. 34B , may be arranged in a spiral configuration. The deflectable arms 1506 may extend proximally and form a height between the first portion 1502 and the second portion 1504. This height can be formed by circumferentially rotating the second portion 1504 in a manner that circumferentially compresses the deflectable arms 1506. The deflectable arms 1506 may thus advance axially proximally to form a height between the first portion 1502 and the second portion 1504 due to compression applied to the deflectable arms 1506. For example, FIG. 34C illustrates deflection of the deflectable arms 1506 in the axial proximal direction due to compression applied to the arms 1506.

[0245] When the circumferential compression is reduced due to an untwisting or twisting motion (e.g., the second portion 1504 is rotated clockwise in the view of FIG. 34B), the height between the first portion 1502 and the second portion 1504 may be reduced. For example, FIG. 34D illustrates such a height change when the deflectable arm 1506 has moved distally due to rotation of the second portion 1504.

[0246] Distal movement of the deflectable arm 1506 can cause the first portion 1502 to pull the liner from the surface 924 of the on-skin sensor assembly 508. The first portion 1502 may be pulled axially from the surface 924 of the on-skin sensor assembly 508.

[0247] During operation, the deflectable arm 1506 can be held in place by circumferential compression applied to the arm. A retainer 1512 can hold the deflectable arm 1506 in compression, for example, as shown in FIG. 34B. Releasing the retainer 1512 can rotate the second portion 1504 of the liner removal component 1500, allowing the deflectable arm 1506 to move distally.

[0248] The resulting configuration of the retainer 1512 and liner removal component 1500 is shown in Figure 34E. The deflectable arm 1506 is flattened to move the first portion 1502 distally, thus allowing the liner to be removed from the surface 924 of the on-skin sensor assembly 508.

[0249] Once the deflectable arms 1506 are flattened, the liner removal component 1500 may be recoupled to the applicator housing 902. Figure 34F shows the deflectable arms 1506 being lowered to collapse the liner removal component 1500. The deflectable arms 1506 may be configured to flex to accommodate the liner removal component 1500 being coupled to the applicator housing 902. The liner removal component 1500 may be recoupled to the applicator housing 902 following placement of the wearable medical device on the skin and retraction of the insertion element 915.

[0250] In embodiments, the retainer 1512 may be configured to rotate relative to the liner removal component 1500 such that rotation of the retainer 1512 does not rotate the liner removal component 1500. In such embodiments, a user may rotate the retainer 1512 to release it from the applicator housing 902 and then axially pull the liner removal component 1500 out of the internal cavity 903 of the applicator housing 902. The axial movement may continue until the liner removal component 1500 is released from the applicator housing 902, at which point the deflectable arms 1506 may rotate to the flat configuration shown in FIG. 34E . The liner removal component 1500 may then be recoupled to the applicator housing 902 following placement of the wearable medical device on the skin and retraction of the insertion element 915.

[0251] In embodiments, the engagement portion of the liner removal component 1500 may be integral with the liner removal component 1500. For example, FIG. 34G illustrates a liner removal component 1500 having an engagement portion 1522 that rotates with the liner removal component 1500. Rotation of the engagement portion 1522 can rotate the second portion 1504 of the liner removal component, and thus, the height of the deflectable arm 1506 can be adjusted.

[0252] 34A-34G, the deflectable arm 1506 may bend to allow the height of the first portion 1502 to be adjusted relative to the second portion 1504. Thus, when the liner removal component 1500 is to be recoupled to the housing 902 after deployment, the deflectable arm 1506 may be deflected to allow the liner removal component 1500 to be recoupled to the housing 902. The liner removal component 1500 thus acts as a collapsible body configured to be collapsed to allow recoupling after use. The liner removal component 1500 may comprise a base for the applicator housing 902 and may cover the interior cavity 903. The liner removal component 1500, in an embodiment, may comprise a cap.

[0253] 35 illustrates one embodiment of a liner removal component 1550 including a single-body insert that can extend axially within the internal cavity 903. The liner removal component 1550 can form a cavity 1552 within the internal cavity 903. The liner removal component 1550 can include a first portion 1553 for supporting the liner and can include a second portion 1554 positioned at a distal opening of the internal cavity 903. The second portion 1554 can include a gripping portion for a user to grasp. The first portion 1553 can be axially spaced from the second portion 1554.

[0254] In embodiments, the liner removal component 1550 may be made from a flexible plastic that may form a blister pack configuration within the interior cavity 903. The liner removal component 1550 may comprise a base for the applicator housing 902 and may cover the interior cavity 903. The liner removal component 1550, in embodiments, may comprise a cap.

[0255] 36A-36B illustrate one embodiment of the liner removal component 1600, where the liner removal component 1600 includes a portion that extends outside of the housing 902. The liner removal component 1600 may comprise all or a portion of the packaging for the applicator 900.

[0256] The applicator housing 902 may include a distal end portion 1602 and a proximal end portion 1604. The opening 905 may be positioned in the distal end portion 1602.

[0257] The liner removal component 1600 may include a first portion 1606 configured to support the liner 1608 by engaging the outer periphery of the liner 1608. The liner 1608 in embodiments may be integral with the first portion 1606 of the liner removal component 1600. In embodiments, the liner 1608 may comprise a separate liner positioned over the first portion 1606 (as shown in FIG. 36A ). The first portion 1606 may include a sheath 1610 that covers the insertion element 915. The sheath 1610, in embodiments, may extend distally from the liner 1608.

[0258] The first portion 1606 can be coupled to an intermediate portion 1612 that extends distally within the internal cavity 903 to a second portion 1614 of the liner removal component 1600. The second portion 1614 can be axially spaced from the first portion 1606. The second portion 1614 can extend outside of the housing 902 and can be coupled to a third portion 1616 that extends to the proximal end portion 1604 of the housing 902. The third portion 1616 can include an opening 1618 through which the applicator housing 902 passes. A cover 1620 can be positioned in the opening 1618 of the third portion 1616 to cover the housing 902. The cover 1620 and the liner removal component 1600 can comprise packaging for the applicator 900.

[0259] In operation, the cover 1620 may be removed from the opening 1618, and the liner removal component 1600 may be pulled distally relative to the applicator 900. The first portion 1606 may pull the liner 1608 off, exposing the surface 924 of the on-skin sensor assembly 508. The liner removal component 1600 may comprise a base for the applicator housing 902 and may cover the interior cavity 903. The liner removal component 1600, in an embodiment, may comprise a cap.

[0260] FIG. 36B illustrates the liner removal component 1600 being withdrawn from the housing and out of the opening 1618.

[0261] The bonding surface for bonding the liner to the liner removal component may have a variety of configurations. As discussed herein, the bonding surface may be an adhesive surface that may include various forms of adhesive. A pressure-sensitive adhesive may be utilized if desired. In embodiments, other forms of adhesive may be utilized. In other embodiments, other forms of bonding surface may be utilized.

[0262] The bonding surface may be located on a distal surface 1702 of the liner 1700 facing opposite the proximal surface that contacts the engagement surface of the on-skin wearable medical device. The bonding surface may be configured to engage an object to pull the liner 1700 from the surface of the patch of the on-skin wearable medical device. In an embodiment, the liner 1700 may include an opening 1704 for the transcutaneous analyte sensor and insertion element to pass through. The liner 1700 may include a central portion 1703 and an edge portion 1705 proximate the edge of the liner 1700. In an embodiment, the central portion 1703 may be proximate the opening 1704.

[0263] The one or more bonding surfaces may have various configurations and may include multiple sections positioned on the distal surface 1702 of the liner. In embodiments, the sections may be positioned in one or more of the central portion 1703 or the edge portion 1705, among other combinations. For example, as shown in FIG. 37F, the sections may be positioned in the edge portion. The sections may be positioned in the central portion, as shown in FIG. 37D. The sections may be positioned in both the central portion and the edge portion, as shown in FIG. 37A. In embodiments, the central portion 1703 may be proximate the opening. The edge portion may be proximate the edge of the liner. The liner, in embodiments, may include one or more bonding regions for bonding the liner to a liner removal component.

[0264] 37A, in embodiments herein, section 1706a may surround opening 1704 and may form a ring around opening 1704. Section 1706b may be positioned at an edge portion 1705 of distal surface 1702 of the liner and may form a dot 1711 at the edge.

[0265] In embodiments, the edge portion disclosed herein may comprise a skirt portion of a liner. Referring to FIG. 2C , skirt portion 1707 of patch 204 may comprise a portion extending radially outward from housing 1709. Thus, skirt portion 1707 may form a skirt around housing 1709. Referring back to FIG. 37A , edge portion 1705 of the liner may comprise a skirt portion of the liner that covers the skirt portion of the patch. In embodiments, positioning one or more bonding surfaces on the skirt portion of the liner can reduce the force required to at least partially sever the liner from the surface of the patch.

[0266] 37B, in embodiments herein, sections 1708a, 1708b, 1708c, and 1708d can include dots 1713a, 1713b, 1713c, and 1713d positioned at the center and edge portions of the liner. Section 1708a can include a ring extending around opening 1704. Sections 1708b, 1708c, and 1708d can each include dots 1713a, 1713b, 1713c, and 1713d positioned at the edge of the liner. In embodiments, one or more dots can be utilized as desired.

[0267] 37C, in embodiments herein, sections 1710a, 1710b, 1710c can include dots 1715a, 1715b, 1715c positioned in the center and edge portions of the liner. Section 1710a can include a ring extending around opening 1704. Sections 1710b, 1710c can each include a strip positioned on the edge of the liner. In embodiments, one or more strips can be utilized as desired.

[0268] 37A-37C may have the advantage of positioning the bonding surface radially outward of the housing of the on-skin sensor assembly 508. This positioning may allow for a more controlled release with a shorter release distance.

[0269] Referring to FIG. 37D, in embodiments herein, the compartment 1712a may surround the opening 1704 or may form a ring around the opening 1704.

[0270] In embodiments, the asymmetric and varied surface area of ​​the bonding surface may result in a lower release force of the liner.

[0271] Referring to FIG. 37E, in embodiments herein, the compartment 1714a may include an elongated strip that extends at an angle relative to the opening 1704.

[0272] Referring to FIG. 37F, in embodiments herein, the section 1716a may include an elongated strip extending along a longitudinal axis relative to the opening 1704.

[0273] 37G, in embodiments herein, section 1718a may include a strip that extends from edge to edge of the liner transverse to the longitudinal axis relative to opening 1704. Such a configuration may result in longitudinal peeling of the liner.

[0274] 37H, in embodiments herein, section 1720a may include a strip that extends from edge to edge of the liner along the longitudinal axis relative to opening 1704. Such a configuration may result in the liner peeling laterally.

[0275] Referring to FIG. 37I, in embodiments herein, the section 1722a may comprise an elongated strip extending centrally along a longitudinal axis relative to the opening 1704 from edge to edge of the liner.

[0276] Referring to FIG. 37J, in embodiments herein, sections 1724a, 1724b may comprise elongated strips extending centrally along either side of opening 1704, along the longitudinal axis relative to opening 1704, from edge to edge of the liner.

[0277] Referring to Figure 37K, in embodiments herein, the liner may include multiple layers. The liner may include bonding surfaces within sections 1726a, 1726b, which may include strips positioned at the edge portions of the liner. The liner layers may include a first portion 1727a and a second portion 1727b, with the first portion 1727a folded over the second portion 1727b. The liner may be folded in a butterfly configuration. Figure 37L illustrates the liner shown in Figure 37K being pulled from the surface 924 of the on-skin wearable medical device. In embodiments, folding the liner may reduce the release force and further increase the release distance.

[0278] In embodiments, the liner may include one or more curved cuts that may extend radially outward from the opening in the liner. For example, Figure 37M illustrates curved cut 1730a on the liner. For example, Figure 37N illustrates multiple curved cuts 1732a, 1732b, 1732c, and 1732d on the liner. For example, Figure 37O illustrates multiple curved cuts 1734a, 1734b, and 1734c on the liner. The curved cuts in Figures 37M-O may result in a spiral peel of the liner, which may reduce the release force but increase the release distance.

[0279] In FIG. 37P, the bonding surface may cover the entire distal surface of the liner.

[0280] Various other configurations of bonding surfaces may be utilized in embodiments herein.

[0281] In embodiments, the liner removal component may include a piercing layer for passage of an insertion element 915, such as a needle. Referring to FIG. 38A , the liner removal component may include such a piercing layer 1800 over an opening 1802 in the liner removal component. Element 1804 may be configured similarly to, for example, liner removal component 928 or any other embodiment of a component disclosed herein. Opening 1802 may be configured similarly to opening 937 or any other embodiment of an opening disclosed herein.

[0282] As shown in Figure 38A, puncturing layer 1800 may be positioned over opening 1802 and may be positioned for insertion element 915, such as a needle, to pass through. A sheath, such as sheath 939, may be positioned on the opposite surface of component 1804 from that shown in Figure 38A. Puncturing layer 1800 may be sandwiched between ring-shaped connecting portions 1806a and 1806b, although other configurations may be utilized as desired.

[0283] FIG. 38B illustrates an aperture 1802 with a piercing layer 1800 in place on a component 1804 .

[0284] An insertion element 915, such as a needle, may extend through the piercing layer 1800 to stabilize the transcutaneous analyte sensor 1808 (shown in FIG. 38C ) relative to the insertion element 915. Thus, the sensor 1808 may be stabilized from becoming dislodged from the insertion element 915 or otherwise mispositioned. Stabilization may occur during transport of the applicator prior to use or immediately prior to use. Stabilization may occur in the horizontal dimension as well as the vertical dimension. Thus, the piercing layer 1800 may form a seal around the insertion element 915 that holds the sensor 1808 in place relative to the insertion element 915.

[0285] For example, Figure 38D illustrates a side view of the stabilization provided by piercing layer 1800. Withdrawing liner removal component 1804 may withdraw liner 926, as shown, for example, in Figure 38E.

[0286] Any of the embodiments of the liner removal component disclosed herein may optionally include a puncturing layer.

[0287] 39A-39E, in embodiments, patch 1900 may include a puncturing layer 1902 for passage of an insertion element 915, such as a needle. The puncturing layer 1902 may be configured for passage of a transcutaneous analyte sensor. The puncturing layer 1902 may be for passage of one or more of the transcutaneous analyte sensor or the insertion element. Patch 1900 may further include an opening 1904 for passage of the needle and the transcutaneous analyte sensor.

[0288] 39A illustrates an assembly view of a patch 1900, which may include multiple layers. The patch 1900 may include, for example, in an embodiment, a base layer 1906, an adhesive layer 1908, and a puncture layer 1902.

[0289] The base layer 1906 may include a distal surface with a surface 1910 for engaging the skin. The surface 1910 may, in embodiments, include an adhesive surface or other form of surface. The base layer 1906 may include a proximal surface 1912 (marked in FIG. 39B ) facing opposite the distal surface of the base layer 1906. In embodiments, the base layer 1906 may include a central opening 1914 through which the central support 952 (as shown in FIG. 26C ) of the retainer 942 may be configured to pass and contact the housing of the on-skin wearable medical device, although in embodiments, the central opening 1914 may be omitted if desired.

[0290] The adhesive layer 1908 may be positioned on a proximal surface 1912 of the base layer 1906 and may be configured to bond the base layer 1906 to a housing of the on-skin wearable medical device. The adhesive layer 1908 may therefore be sized to the width and length of the housing of the on-skin wearable medical device, which may be less than the entire width and length of the base layer 1906. For example, FIG. 39B shows an exemplary size of the adhesive layer 1908 relative to the base layer 1906. The adhesive layer may include a distal surface 1916 and a proximal surface 1918 (marked in FIG. 39B ). The proximal surface 1918, in embodiments, may be configured to bond to the distal surface of the housing of the on-skin wearable medical device. The proximal surface 1918 may comprise an adhesive surface for adhering the patch 1900 to the housing. In embodiments, adhesive layer 1908 may include a central opening 1914a that may be aligned with central opening 1914 in base layer 1906 and may provide a similar function to central opening 1914 in base layer 1906. In embodiments, adhesive layer 1908 may include an opening 1904a that may be aligned with opening 1904 and may provide a similar function to opening 1904 in base layer 1906.

[0291] The puncture layer 1902 may be positioned on the adhesive layer 1908, with the adhesive layer 1908 sandwiched between the puncture layer 1902 and the base layer 1906. The puncture layer 1902 may be a first layer of multiple layers of the patch 1900 layered adjacent to a second layer (e.g., the adhesive layer 1908) of the multiple layers. The puncture layer 1902 may be sandwiched between the base layer 1906 and the housing of the on-skin wearable medical device, and between the adhesive layer 1908 and the housing of the on-skin wearable medical device. The adhesive layer 1908 may be sandwiched between the base layer 1906 and the puncture layer 1902. The puncture layer 1902 may be positioned on a proximal surface 1918 of the adhesive layer 1908 and on a proximal side of the base layer 1906. In embodiments, the location of puncture layer 1902 may vary, for example, it may be sandwiched between adhesive layer 1908 and base layer 1906, or it may be on surface 1910 of base layer 1906. In embodiments, puncture layer 1902 may be integral with either base layer 1906 or adhesive layer 1908.

[0292] In embodiments, the puncture layer 1902 may cover the opening 1904 in the base layer 1906 and the opening 1904a in the adhesive layer 1908. For example, Figure 39B illustrates an assembled view of the patch 1900 in which the adhesive layer 1908 is on the base layer 1906 and the puncture layer 1902 covers the openings 1904a, 1904.

[0293] An insertion element 915, such as a needle, may extend through the puncturing layer 1902 to stabilize the transcutaneous analyte sensor against the insertion element 915. FIG. 39C illustrates the housing of an on-skin wearable medical device positioned on a patch 1900, for example, with a transcutaneous analyte sensor 1920 passing through the puncturing layer 1902. The on-skin wearable medical device is positioned within an interior cavity of and held by the applicator housing. The insertion element 915 passes through the puncturing layer 1902, and the transcutaneous analyte sensor 1920 is positioned within a channel of the insertion element 915. As shown, the puncturing layer 1902 may be configured to hold the transcutaneous analyte sensor within the channel of the insertion element 915. The insertion element 915 and transcutaneous analyte sensor 1920 are shown in a pre-deployment state, with the insertion element 915 in position for placing the transcutaneous analyte sensor 1920 on the skin.

[0294] Thus, the piercing layer 1902 can be stabilized to prevent the sensor 1920 from being dislodged from the insert element 915 or otherwise mispositioned. Stabilization can occur during transport of the applicator prior to use or immediately prior to use. Stabilization can occur in horizontal as well as vertical dimensions. The piercing layer 1902 can stabilize the analyte sensor in horizontal as well as vertical dimensions to prevent it from being dislodged from the channel of the insert element. Thus, the piercing layer 1902 may form a seal around the insert element 915 that holds the sensor 1920 in place relative to the insert element 915, for example, within the channel of the insert element 915.

[0295] 39D illustrates a side view of the sensor 1920 and insert element 915 stabilized by the puncturing layer 1902. FIG. 39E illustrates a bottom perspective view of the insert element 915 shown stabilized by the puncturing layer 1902.

[0296] Upon placement, the insertion element 915 may be withdrawn or retracted proximally through the puncturing layer 1902, with the transcutaneous analyte sensor 1920 passing through or extending through the puncturing layer 1902 and remaining in place within the recipient's skin.

[0297] Any embodiment of the liner removal component disclosed herein may be utilized in combination with a puncture layer of a patch, if desired. In embodiments, the puncture layer of a patch may be utilized in combination with a puncture layer of a liner removal component, if desired. Various other combinations may be utilized in embodiments.

[0298] 39A and 39B , in embodiments, the puncturing layer 1902 may include a puncturing portion 2000 and a support portion 2002 positioned radially outward of the puncturing portion 2000. The puncturing portion 2000 may form a portion of the puncturing layer 1902 for passage of one or more of the transcutaneous analyte sensors or insertion elements 915. For example, the puncturing portion 2000 may be aligned at a position that is within a perimeter of the opening 1904 in the base layer 1906 and the opening 1904a in the adhesive layer 1908 (e.g., as shown in FIG. 39B ).

[0299] The support portion 2002 may be configured to support the piercing portion 2000. Such support can reduce the likelihood that the piercing layer 1902 will separate or peel away from the remainder of the patch 1900 or another component of the on-skin wearable medical device when a force is applied to the piercing portion 2000. For example, a reduced likelihood of the piercing portion 2000 separating or peeling away can occur upon initial puncture by a sensor or insertion element through the piercing portion 2000, or upon withdrawal of an insertion element through the piercing portion 2000 after insertion of the sensor into the recipient's skin. A reduced likelihood of separation or peeling can occur during transport of the on-skin sensor assembly (e.g., force applied to the piercing layer 1902 due to movement of the on-skin sensor assembly).

[0300] The support portion 2002 may be configured to overlay a portion of the patch to support the puncturing portion 2000. For example, in embodiments in which the patch includes multiple layers, the support portion 2002 may overlay another of the multiple layers to support the puncturing portion 2000. The overlaid layer may include one or more of the adhesive layer 1908 or the base layer 1906. With reference to FIG. 39B , for example, the support portion 2002 overlies and is adhered to the adhesive layer 1908. The support portion 2002 may be adhered to an adhesive proximal surface 1918 of the adhesive layer 1908.

[0301] In embodiments, the support portion 2002 may be positioned within a cavity in the housing of the on-skin sensor assembly 508. Such positioning may reduce any adverse effects of the height or thickness of the support portion 2002 in relation to the fit of the patch 1900 on the housing. In embodiments, at least a portion of the puncture layer 1902 may extend along the cavity. With reference to FIG. 40 , for example, the housing 2010 of the on-skin sensor assembly 508 may include a cavity 2012. The cavity 2012 may extend proximally from a distal surface 2014 of the housing 2010 and may comprise a recess in the distal surface 2014 of the housing 2010.

[0302] The cavity 2012 may be configured to receive a portion of the transcutaneous analyte sensor 1920. For example, the transcutaneous analyte sensor 1920 may include an insertion portion 2016 configured to be disposed within the skin of a recipient and may include a coupling portion 2018 configured to couple to the housing 2010. A bending portion 2024 may be positioned between the insertion portion 2016 and the coupling portion 2018. The cavity 2012 may receive the coupling portion 2018 of the transcutaneous analyte sensor 1920 and one or more electrical connections 2020 of the coupling portion 2018 to the electronics 2022 (e.g., an electronic board or printed circuit board, among others) of the on-skin sensor assembly. In an embodiment, the cavity 2012 may receive the bending portion 2024 of the transcutaneous analyte sensor 1920. The cavity 2012 may include an insertion channel 2026 into which the bending portion 2024 may be aligned. The insertion channel 2026 may be configured for the insertion element 915 to pass through to insert the transcutaneous analyte sensor 1920 into the skin of a recipient.

[0303] Figure 41A illustrates a bottom or distal view of the on-skin sensor assembly 508. The outer edge of the base layer 1906 is excluded from the view in Figure 41A. The puncturing layer 1902 is shown positioned within the cavity 2012 of the housing 2010.

[0304] The support portion 2002 may extend circumferentially around the entire puncture portion 2000 and may include a ring portion 2028 that overlaps the adhesive layer 1908. The support portion 2002 may include an elongate arm 2030 that extends radially outward from the puncture portion 2000. In embodiments, the elongate arm 2030 may extend along the cavity 2012. For example, the elongate arm 2030 may extend along the longitudinal axis 2032 of the cavity 2012. The elongate arm 2030 may extend along the cavity 2012 to increase the amount of the support portion 2002 that overlaps the adhesive layer 1908, but remains positioned within the cavity 2012 to reduce any adverse effects of the height or thickness of the support portion 2002 in relation to the fit of the patch 1900 on the housing 2010.

[0305] 41B illustrates a cross-sectional view of the puncture layer 1902 with respect to the cavity 2012, for example, along line BB shown in FIG. 41A. The puncture layer 1902 is shown positioned within the cavity 2012 of the housing 2010, with the adhesive proximal surface 1918 of the adhesive layer 1908 being flush or coplanar with the distal surface 2014 of the housing 2010.

[0306] In embodiments, the configuration of the puncture layer 1902 may vary. For example, FIG. 42 illustrates an embodiment in which the puncture layer 2040 has elongate arms 2041 that are longer than the elongate arms 2030 shown in FIG. 41A. The elongate arms 2041 may extend the entire length of the cavity 2012 (whereas the elongate arms 2030 shown in FIG. 41A may extend a portion or approximately half the length of the cavity 2012). The puncture layer 2040 may have a ring portion 2042 with an overlap of the adhesive layer 1908 that is smaller in diameter than the ring portion 2028 shown in FIG. 41A. Various other configurations of the puncture layer may be utilized as desired.

[0307] The puncturing layer disclosed herein may include a stabilizing body that may be configured to stabilize the position of the transcutaneous analyte sensor relative to the insertion element of the transcutaneous analyte sensor. The stabilizing body may stabilize the transcutaneous analyte sensor in the horizontal dimension from dislodging from the channel of the insertion element. In embodiments, the stabilizing body may be configured to contact the transcutaneous analyte sensor to stabilize the transcutaneous analyte sensor from dislodging from the channel of the insertion element. The stabilizing body may have various forms.

[0308] 43A-43C, the stabilizing body may comprise a spiral body 2043. The spiral body 2043 may be configured to extend around the insertion element 915 of the transcutaneous analyte sensor to stabilize the position of the transcutaneous analyte sensor relative to the insertion element 915.

[0309] 43A, for example, illustrates a bottom or distal view of on-skin sensor assembly 2045. On-skin sensor assembly 2045 may be configured similarly to on-skin sensor assembly 508 unless otherwise noted. On-skin sensor assembly 2045 may include a housing 2010 and may include a patch. The outer edge of the base layer of the patch is excluded from view in FIG. 43A.

[0310] The patch may be coupled to the housing 2010 and may include a first surface 2044 for engaging the skin, similar to surface 1910 of base layer 1906 shown in FIG. 39A . At least a portion of the patch may comprise a spiral 2043 configured to extend around insert element 915. For example, the patch may include a single layer and may have a portion cut into a spiral shape, as shown in FIG. 43A . In embodiments, the patch may include multiple layers, and one or more of the layers may be cut into a spiral shape. In the embodiment shown in FIG. 43A , base layer 2046 may include spiral 2043. Base layer 2046 may otherwise be configured similarly to base layer 1906 shown in FIG. 39A and may be coupled to housing 2010 via adhesive layer 1908.

[0311] The spiral 2043 is shown in FIG. 43A as having a flat coil shape. The spiral 2043 may include an outer arm 2048 that spirals inward toward the inner arm 2050. The outer arm 2048 may be positioned radially outward of the inner arm 2050. The inner arm 2050 may extend around the outer surface of the insert element 915 and may cover the opening 2052 of the channel of the insert element 915. Thus, the inner arm 2050 may block or impede the transcutaneous analyte sensor 1920 from dislodging from the channel of the insert element in the horizontal dimension. Thus, the spiral 2043 may stabilize the position of the transcutaneous analyte sensor 1920 relative to the insert element 915. The spiral 2043 may contact the transcutaneous analyte sensor 1920 to stabilize it from dislodging from the channel of the insert element 915 in the horizontal dimension.

[0312] The spiral 2043, shown in a flat coil shape in Figure 43A, may be extended distally to form a helical shape in the extended position, as shown in Figure 43B. The extended position may be a configuration for transport or storage of the on-skin sensor assembly 2045. The spiral 2043 may stabilize the position of the transcutaneous analyte sensor 1920 relative to the insertion element 915 in such a configuration.

[0313] The spiral 2043 may protrude from the first surface 2044 of the patch in the extended position shown in FIG. 43B. The inner arm 2050 in the extended position may extend further around the outer surface of the insert element 915 and may cover the opening 2052 (marked in FIG. 43A) of the channel of the insert element 915. The helical shape of the spiral 2043 may extend along the longitudinal axis of the insert element 915.

[0314] Upon inserting the insertion element 915 and transcutaneous analyte sensor 1920 into the recipient's skin, the spiral 2043 may be pressed proximally toward the housing 2010 by the recipient's skin. The spiral 2043 may then move from the extended position shown in FIG. 43B to the retracted position shown in FIGS. 43A and 43C. The spiral 2043 may, for example, be collapsed in the retracted position and have a flat coil shape. In the retracted position, the spiral 2043 may be positioned flush with the first surface 2044 of the patch or may be retracted therefrom. The insertion element 915 may then be retracted from the recipient's skin 2054, leaving the transcutaneous analyte sensor 1920 in place within the recipient's skin 2054.

[0315] The features of Figures 43A-43C may be used alone or in conjunction with any method, device, or system disclosed herein.

[0316] 44 illustrates an embodiment including a stabilizer 2060 configured to be positioned within a cavity in a housing of an on-skin sensor assembly. The cavity may include a cavity 2012 configured to receive a portion of a transcutaneous analyte sensor 1920.

[0317] The stabilizing body 2060 may include a body configured to be positioned axially offset from the longitudinal axis of the insert element 915. The stabilizing body 2060 may be positioned to cover the opening 2052 of the channel of the insert element 915. Thus, the stabilizing body 2060 can block or impede the transcutaneous analyte sensor 1920 from dislodging from the channel of the insert element in the horizontal dimension. The stabilizing body 2060 may be configured to contact the transcutaneous analyte sensor 1920 to stabilize the transcutaneous analyte sensor 1920 from dislodging from the channel of the insert element 915 in the horizontal dimension.

[0318] In embodiments, the stabilizer 2060 may have a recess 2062 in which the insert element 915 may be positioned. The inner surface 2064 of the recess 2062 may be positioned to cover the opening 2052 of the channel of the insert element 915.

[0319] In embodiments, the stabilizer 2060 may comprise an insert for the cavity 2012. The stabilizer 2060 may be form-fit to fit within the interior walls of the cavity 2012 and may be positioned with the insert element 915 within the recess 2062. In embodiments, the stabilizer 2060 may comprise foam or may have other forms as desired.

[0320] The stabilizing body 2060 can stabilize the transcutaneous analyte sensor 1920 prior to inserting the transcutaneous analyte sensor 1920 into the recipient's skin. Stabilization can occur during transport or otherwise prior to inserting the sensor 1920 into the recipient's skin. Once inserted into the recipient's skin, the insertion element 915 can be withdrawn from the recipient's skin and the housing 2010 while the transcutaneous analyte sensor 1920 remains positioned within the recipient's skin. Thus, the insertion element 915 can slide proximally against the inner surface 2064 of the recess 2062 of the stabilizing body 2060.

[0321] The features of FIG. 44 may be utilized alone or in conjunction with any embodiment method, device, or system disclosed herein.

[0322] 45A-45C illustrate one embodiment including a stabilizer 2070 that can be coupled to a cap 2072 of an applicator system. The cap 2072 can be configured similarly to the retention body 942 or cap shown in FIG. 26C, for example, unless otherwise stated. The cap 2072 can include an engagement portion 2074 configured to engage a portion of the applicator housing and can include an outer surface or gripping portion 2076 that can be configured to be grasped by a user. The engagement portion 2074 can be configured to engage the outer surface of the applicator housing. The engagement portion 2074 can include, for example, threads configured to engage with threads on the outer surface of the applicator housing, or can have other configurations as desired. The outer surface or gripping portion 2076 can be configured to be grasped by a user to disengage the engagement portion 2074 from the applicator housing. For example, a user may grasp gripping portion 2076 and rotate cap 2072 to disengage the threads of engagement portion 2074 from the outer surface of the applicator housing. Cap 2072 may have other configurations in embodiments. Cap 2072 may comprise a retainer for the applicator system, similar to retainer 942 shown in FIG. 26C.

[0323] The cap 2072 may include an outer portion 2078 with a gripping portion 2076 and may include a central portion 2080. The central portion 2080 may include a central support 2082 (marked in FIG. 45C), which may be configured similarly to the central support 952 shown in FIG. 26C, unless otherwise noted.

[0324] The cap 2072 may comprise a cap for a cavity 903 (marked in FIG. 45B) for holding an on-skin wearable medical device therein. The cavity 903 and applicator housing 902 marked in FIG. 45B may be configured similarly to the respective cavity 903 and applicator housing 902 shown in FIG. 26A unless otherwise noted.

[0325] 45A, stabilizer 2070 can include a bearing surface 2084 configured to stabilize the position of the transcutaneous analyte sensor relative to the insertion element. Bearing surface 2084 can be configured, for example, to cover the opening of the channel of insert element 915 (marked in FIG. 45C). Thus, bearing surface 2084 can block or prevent the transcutaneous analyte sensor from dislodging from the channel of the insert element in the horizontal dimension. Bearing surface 2084 can be configured to contact the transcutaneous analyte sensor to stabilize it from dislodging from the channel of insert element 915 in the horizontal dimension.

[0326] The bearing surface 2084 may include a curved bearing surface. Thus, as the stabilizer 2070 and bearing surface 2084 rotate, the bearing surface 2084 may be configured to rotate relative to the insert element 915. In embodiments, the stabilizer 2070 may have a conical shape (as shown in FIG. 45A ). Thus, as the stabilizer 2070 moves axially distally, the diameter of the bearing surface 2084 that impinges on the insert element 915 may decrease. Such a feature may gradually reduce friction of the bearing surface 2084 against the insert element 915 as the stabilizer 2070 is moved axially distally. In embodiments, the stabilizer 2070 may have other shapes (e.g., cylindrical) as desired.

[0327] 45C , in embodiments, stabilizer 2070 may be flexible and configured to flex to accommodate the position of insert element 915. Stabilizer 2070 may include, for example, a layer 2085 of flexible material surrounding cavity 2087. Layer 2085 may include a bearing surface 2084 as an outer surface of stabilizer 2070. As shown in FIG. 45C , bearing surface 2084 may contact the outer surface of insert element 915 and cover the opening of the channel in insert element 915 to retain the transcutaneous analyte sensor in the channel.

[0328] The stabilizer 2070 may be coupled to the central support 2082, although other coupling locations may be utilized as desired. The location on the central support 2082 may, in embodiments, allow the stabilizer 2070 to rotate about the central axis of the cap 2072.

[0329] 45B and 45C illustrate cap 2072 coupled to applicator housing 902. At a desired time, cap 2072 can be removed from applicator housing 902. In embodiments, cap 2072 can be rotated relative to applicator housing 902 for removal (e.g., via threads comprising engagement portion 2074 of cap 2072). For example, cap 2072 can be configured to couple to applicator housing 902 and to unscrew and separate from applicator housing 902. In embodiments, other forms of removal can be utilized (e.g., axial pulling or other forms of release from applicator housing 902).

[0330] The bearing surface 2084 may be configured to rotate with the cap 2072. For example, when the cap 2072 is unscrewed from the applicator housing 902, the bearing surface 2084 may rotate with the cap 2072 relative to the insert element 915. The stabilizer 2070 may be moved axially distally relative to the insert element 915 when the cap 2072 is unscrewed from the applicator housing 902. The bearing surface 2084 may slide against the outer surface of the insert element 915 as the stabilizer 2070 rotates with the cap 2072. The diameter of the bearing surface 2084 that impacts the insert element 915 may be reduced during axial movement of the stabilizer 2070 due to the conical shape of the stabilizer 2070.

[0331] With the cap 2072 removed from the applicator housing 902, the on-skin wearable medical device may be in place for placement on the skin of a recipient. The stabilizing body 2070 may stabilize the transcutaneous analyte sensor 1920 prior to inserting the transcutaneous analyte sensor 1920 into the skin of the recipient. Stabilization may occur during transport or otherwise prior to inserting the sensor 1920 into the skin of the recipient.

[0332] The features of Figures 45A-43C may be utilized alone or in conjunction with any embodiment of the methods, devices, or systems disclosed herein.

[0333] In embodiments, the systems and apparatus may include one or more moisture passages configured for the removal of moisture, which may be located distal to the housing of the on-skin wearable medical device system.

[0334] Moisture may be located at various locations relative to the on-skin wearable medical device system, for example. In embodiments in which the on-skin wearable medical device system includes a housing, moisture may be located distal to the housing due to moisture emanating from the external environment (e.g., from a shower, pool, rain, or other moisture source) or due to moisture emanating from the recipient's body (e.g., sweat, blood, or other moisture source). Moisture distal to the housing may be undesirable for a variety of reasons, including irritation to the recipient's skin or adverse effects on components of the on-skin wearable medical device system. In embodiments, moisture proximate to the skin insertion site of the transcutaneous analyte sensor may be undesirable. Such moisture may cause infection or undesirable consequences at the skin insertion site. Therefore, it may be desirable to remove moisture, particularly moisture located distal to such a housing.

[0335] 46 , a distal perspective view of a housing 2090 for an on-skin wearable medical device system is shown. The housing 2090 may be configured similarly to the housing 2010 shown in FIG. 40 , unless otherwise noted. The housing 2090 may include a distal surface 2092 configured to face the skin. The distal surface 2092 may extend radially outward to an outer periphery 2094 of the housing 2090. The housing 2090 may include one or more side surfaces 2096 that may contact the distal surface 2092 at the outer periphery 2094. The housing 2090 may include a proximal surface that may be configured similarly to the proximal surface 2098 shown in FIG. 40 , for example.

[0336] The housing 2090, in embodiments, may include a recess 2100 on an outer periphery 2094 of the housing 2090. The recess 2100 may extend radially inward on a distal surface 2092 of the housing 2090. The recess 2100 may define a cavity in a side surface 2096 of the housing 2090. The recess 2100 may be configured to receive, for example, the retention elements 920a, 920b shown in FIG. 26A, or may have other uses as desired.

[0337] The distal surface 2092 of the housing 2090 may include a cavity 2102, which may be configured similarly to the cavity 2012 shown in FIG. 40, for example. The cavity 2102 may comprise a recess in the distal surface 2092 of the housing 2090, which may extend proximally from the distal surface 2092. The cavity 2102 may be configured to receive a portion of the transcutaneous analyte sensor, similar to the configuration of the cavity 2012 shown in FIG. 40. The cavity 2102 may further include an insertion channel 2104 configured to receive the insertion element 915 therethrough to insert the transcutaneous analyte sensor into the skin of a recipient, similar to the configuration of the insertion channel 2026 shown in FIG.

[0338] The distal surface 2092 of the housing 2090 can include a central region 2106 and a peripheral region 2108 positioned radially outward of the central region 2106. The central region 2106 can include a region of the distal surface 2092 where a transcutaneous analyte sensor can be inserted into the skin (e.g., in an insertion channel 2104 of the housing 2090). The peripheral region 2108 can be positioned proximate the outer periphery 2094 of the housing 2090.

[0339] 46 , in embodiments, the distal surface 2092 of the housing 2090 may include at least one channel forming at least a portion of one or more moisture passageways configured for the removal of moisture distally of the housing. For example, the channel 2110 may comprise a cutout portion or recess in the distal surface 2092 extending proximally from the distal surface 2092. The channel 2110 may be configured for moisture to pass through to remove moisture from distally of the housing. The channel 2110 may extend outward from the cavity 2102 to the outer periphery 2094 of the housing 2090, for example. The channel 2110 may connect the cavity 2102 to a side surface 2096 and may include a cutout portion in the side surface 2096.

[0340] The channels 2110 may be configured to remove moisture in a direction toward the periphery 2094 of the housing 2090. The channels 2110 may, for example, allow moisture to travel through the channels 2110 to the periphery 2094 of the housing 2090. The moisture may be present within the cavity 2102 or elsewhere associated with the housing 2090.

[0341] In embodiments, the channel 2110 may be configured to remove moisture located proximate to the insertion site of the transcutaneous analyte sensor into the skin. The transcutaneous analyte sensor may be inserted into the skin, for example, distal to the insertion channel 2104. Moisture proximate to the insertion site of the transcutaneous analyte sensor into the skin may be located within the cavity 2102. The moisture may be transported to the channel 2110 for removal outside the periphery 2094 of the housing 2090. The moisture may be removed due to evaporation or other removal of moisture from the vicinity of the system.

[0342] In embodiments, the channels 2110 may be configured to wick moisture distal to the housing 2090. The channels 2110 may have, for example, a geometry or other configuration that causes wicking to occur. Wicking can transport moisture outside the perimeter 2094 of the housing 2090 for evaporation or other removal of the moisture from the vicinity of the system.

[0343] The patch may be coupled to the housing 2090 and may be configured similar to the patch embodiments disclosed herein. The patch may include a first surface for engaging the skin, for example, similar to surface 1910 shown in FIG. 39A . The patch may be positioned distal to the housing 2090. The patch may overlie the distal surface 2092 of the housing 2090 and cover the cavity 2102 and the channel 2110. However, the channel 2110 may be elevated proximally from the proximal surface of the patch and may be configured to remove moisture located between the patch and the distal surface 2092 of the housing 2090.

[0344] The patch can have a variety of configurations in embodiments. For example, the patch can lack a puncture layer in embodiments, or can include a single layer or multiple layers as desired. The patch can include an adhesive layer 1908 and a base layer 1906, but exclude a puncture layer, as shown in FIG. 39A, for example. In embodiments, the patch can include a puncture layer.

[0345] FIG. 47A illustrates a distal view of a patch 2112 including one or more moisture passageways configured to remove moisture. The moisture may be located distal to the housing 2114 of the on-skin wearable medical device system. The housing 2114 may be configured similarly to the housing 2090 shown in FIG. 46. The housing 2114 may include a cavity 2115, which may be configured similarly to the cavity 2102 shown in FIG. 46, for example. However, the housing 2114 may, in embodiments, exclude or include the channel 2110 shown in FIG. 46.

[0346] The patch 2112 may include at least one channel that may form at least a portion of one or more moisture passageways. The at least one channel may be formed in a variety of ways. For example, the at least one channel may be formed as a notch in a surface or portion of the patch that may form the channel. In embodiments, the patch may be configured to include multiple layers that are stacked together in a manner that forms the at least one channel. Combinations of layers and notches, or other features, may be utilized in embodiments, as desired.

[0347] 47B, for example, illustrates an assembly view of patch 2112. FIG. 47B illustrates patch 2112 with the layers of patch 2112 separated and illustrates patch 2112 assembled on backing layer 2116.

[0348] The patch 2112 may include multiple layers, which may include a base layer 2118, an adhesive layer 2120, and a puncture layer 2122. The base layer 2118 may be configured similar to, for example, the base layer 1906 shown in FIG. 39A. The base layer 2118 may include a first surface 2124 for engaging the skin, similar to surface 1910 shown in FIG. 39A. The base layer 2118 may be configured to protrude radially outward from an outer periphery 2126 of the housing 2114 to form a skirt portion 2128 (marked in FIG. 47A ) of the patch 2112.

[0349] 39A , but may include different features identified herein. For example, the adhesive layer 2120 may be shaped with a perimeter 2130 that extends to the perimeter 2126 of the housing 2114. The adhesive layer 2120 may include a recess in the perimeter of the adhesive layer 2120 that may match the shape of a recess 2133 in the perimeter 2126 of the housing 2114.

[0350] The adhesive layer 2120 may include notches 2134a, 2134b that form channels in the adhesive layer 2120. While two notches 2134a, 2134b are shown in Figures 47A and 47B, in embodiments, a greater or lesser number may be provided. The notches 2134a, 2134b may include channels that form at least a portion of one or more moisture passageways.

[0351] The adhesive layer 2120 may be layered proximally on the base layer 2118 and may include a distal adhesive surface for bonding with the base layer 2118. The adhesive layer 2120 may further include a proximal adhesive surface for adhering to a distal surface of the housing 2114 and for adhering to a distal surface of the puncture layer 2122.

[0352] 39A 。 The puncture layer 2122 may be configured similarly to the puncture layer 1902 shown in Figure 39A , unless otherwise noted. The puncture layer 2122 may be positioned on the adhesive layer 2120 or may be sandwiched between the adhesive layer 2120 and the distal surface of the housing 2114. The puncture layer 2122 may be adhered to the adhesive layer 2120.

[0353] In embodiments, the lancing layer 2122 may lack an adhesive. Such a feature may reduce the likelihood of adhesion between the lancing layer 2122 and an insertion element or transcutaneous analyte sensor passing through the lancing layer 2122. In embodiments, the lancing layer 2122 may include an adhesive.

[0354] 47A, the puncturing layer 2122 may include a puncturing portion 2136 and a support portion 2138 positioned radially outward from the puncturing portion 2136. The support portion 2138 may be configured similarly to the support portion 2002 shown in FIG. 39B, for example, and may have elongated arms 2140 and a ring portion 2142 that surrounds the puncturing portion 2136.

[0355] The elongate arm 2140 can extend at an angle relative to the longitudinal axis 2144 of the housing 2114. The elongate arm 2140 may extend along the longitudinal axis of the cavity 2115, for example, similar to the elongate arm 2030 shown in FIG. 41A. The puncture layer 2122 may form a V-shape, as shown in FIG. 47A. The V-shape may be formed by the angle between the elongate arm 2140 and the ring portion 2142.

[0356] The cutout portion 2134b of the adhesive layer 2120 can include a channel that forms at least a portion of a moisture passageway for removing moisture located distal to the housing 2114. The cutout portion 2134b can extend outward, for example, to the outer periphery 2126 of the housing 2114 for removal of moisture. The cutout portion 2134b can extend along the cavity 2115 of the housing 2114 to channel moisture that may be located along the cavity 2115 toward the outer periphery 2126 of the housing 2114.

[0357] Figure 47C illustrates a cross-sectional view of the housing 2114 and patch 2112 along line CC shown in Figure 47A. Cutout portion 2134b of adhesive layer 2120 is shown to include sidewalls 2146 that bound a channel extending along cavity 2115 for removing moisture distal to the housing 2114.

[0358] Figure 47D illustrates a cross-sectional view of the housing 2114 and patch 2112 along line DD shown in Figure 47A. The elongated arms 2140 of the puncture layer 2122 are shown extending along the cavity 2115. The space provided around the puncture layer 2122 may comprise a channel that allows moisture to pass into a portion of the channel shown in Figure 47C and to the periphery 2126 of the housing 2114 (marked in Figure 47A).

[0359] The channel configurations shown in Figures 47C and 47D can allow for the removal of moisture proximate the insertion site of the transcutaneous analyte sensor into the skin. For example, moisture located at the puncturing portion 2136 shown in Figure 47A can travel along the elongated arms 2140 of the support portion 2138 to the channels shown in Figure 47C. This can reduce the likelihood of moisture accumulation at the insertion site and possible infection or other adverse consequences. Moisture can be removed in a direction toward the outer periphery 2126 of the housing 2114 (marked in Figure 47A). Moisture may include moisture located between the patch 2112 and the distal surface of the housing 2114.

[0360] Referring to FIG. 47A, the channels shown in FIGS. 47C and 47D may extend from a region 2150 of the patch 2112 adjacent the site of insertion of the transcutaneous analyte sensor into the skin toward the outer periphery 2126 of the housing 2114.

[0361] The cutout portion 2134a of the adhesive layer 2120 may include a second channel that forms at least a portion of a moisture passageway for removing moisture distal to the housing 2114. The cutout portion 2134a of the adhesive layer 2120 may extend inward from the outer periphery 2126 of the housing 2114 to the puncture portion 2136 of the puncture layer 2122. The cutout portion 2134a may extend perpendicular to the longitudinal axis 2144 of the housing 2114 or may have another angle as desired.

[0362] The lancing layer 2122 may overlap the cutout portion 2134a proximate the insertion site of the transcutaneous analyte sensor into the skin and at a ring portion 2142 of the lancing layer 2122. Figure 47E illustrates a cross-sectional view of the housing 2114 and patch 2112 along line E-E of Figure 47A. The cutout portion 2134a of the adhesive layer 2120 is shown to include a sidewall 2152 that bounds the lancing layer 2122 with a channel positioned between the base layer 2118 and a distal surface 2154 of the housing 2114 for removing moisture distal to the housing 2114. The channel shown in Figure 47E may connect with the channel shown in Figure 47F.

[0363] The puncture layer 2122 may further space the adhesive layer 2120 from the distal surface 2154 of the housing 2114 to form a channel 2156 along the sidewall 2158 of the puncture layer 2122. The channel 2156 may comprise a gap formed by the adhesive layer 2120 bending around the puncture layer 2122 to contact the distal surface 2154 of the housing 2114. The channel 2156 may comprise a moisture passageway for removing moisture. The channel 2156 can transport moisture to the channel shown in FIG. 47F for removal.

[0364] In embodiments, one or more moisture passageways may be formed between the proximal surface 2153 of the puncture layer 2122 and the distal surface 2154 of the housing 2114. For example, the proximal surface 2153 of the puncture layer 2122 may lack adhesive to the distal surface 2154 of the housing 2114. Thus, moisture may be carried in the passageways between the proximal surface 2153 of the puncture layer 2122 and the distal surface 2154 of the housing 2114.

[0365] Figure 47F illustrates a cross-sectional view of the housing 2114 and patch 2112 along line FF shown in Figure 47A. Sidewall 2152 is shown to bound a channel positioned between the base layer 2118 and the distal surface 2154 of the housing 2114. The channel shown in Figure 47F can transport moisture to the periphery 2126 of the housing 2114.

[0366] The channel configurations shown in Figures 47E and 47F can allow for the removal of moisture proximate the insertion site of the transcutaneous analyte sensor into the skin. For example, moisture located at the puncture portion 2136 shown in Figure 47A can migrate through the channels shown in Figures 47E and 47F. This can reduce the likelihood of moisture accumulation at the insertion site and possible infection or other adverse consequences. Moisture can be removed in a direction toward the outer periphery 2126 of the housing 2114 (marked in Figure 47A). Moisture may include moisture located between the patch 2112 and the distal surface of the housing 2114.

[0367] Referring to FIG. 47A, the channels shown in FIGS. 47E and 47F may extend from a region 2150 of the patch 2112 adjacent the site of insertion of the transcutaneous analyte sensor into the skin toward the outer periphery 2126 of the housing 2114.

[0368] 47A-47F may be configured to wick moisture located distally of the housing 2114. The channels or moisture passages may have, for example, a geometry or other configuration that causes wicking to occur. Wicking can transport moisture outside the perimeter 2126 of the housing 2114 for evaporation or other removal of the moisture from the vicinity of the system.

[0369] In embodiments, the configuration of the moisture passages may be varied as desired.

[0370] Figure 48A illustrates an embodiment including, for example, the housing 2114 and base layer 2118 shown in Figure 47A. The configuration of the adhesive layer 2160 and puncture layer 2162 may be similar to the configuration of the respective adhesive layer 2120 and puncture layer 2122 shown in Figure 47A, unless otherwise noted.

[0371] 48B illustrates an assembly view of patch 2164. FIG. 48B illustrates patch 2164 with the layers of patch 2164 separated and illustrates patch 2164 assembled on backing layer 2166.

[0372] 48A and 48B, the adhesive layer 2160 can be shaped with a perimeter 2168 that extends to the perimeter 2126 of the housing 2114. The adhesive layer 2160 can include a recess in the perimeter of the adhesive layer 2160 that can match the shape of the recess 2133 in the perimeter 2126 of the housing 2114. The adhesive layer 2160 can include a distal adhesive surface configured to adhere to the base layer 2118 and a proximal adhesive surface configured to adhere to the distal surface of the housing 2114 and the puncture layer 2162.

[0373] 47A . The support portion 2172 of the puncture layer 2162 may include a ring portion 2174 that may be positioned circumferentially around the puncture portion 2170. The support portion 2172 may include one or more elongate arms 2176a-2176e, each of which may extend radially outward from the puncture portion 2170 of the puncture layer 2162.

[0374] In embodiments, the elongate arms 2176a-2176e may extend from a region 2178 of the patch 2164 proximate the skin insertion site of the transcutaneous analyte sensor toward the periphery 2126 of the housing 2114. The elongate arms 2176a, 2176b, 2176d, 2176e may be angled relative to the longitudinal axis of the housing 2114, and the elongate arm 2176c may be centered along the longitudinal axis of the housing 2114 and extend along the longitudinal axis of the housing 2114.

[0375] At least two of elongate arms 2176a-2176e may intersect. For example, elongate arm 2176e may intersect with elongate arm 2176c. Elongate arm 2176d may also intersect with elongate arm 2176c. Elongate arms 2176d, 2176e may form a V-shape with puncturing layer 2162 due to the angle of elongate arm 2176d relative to elongate arm 2176e. Elongate arms 2176a, 2176b may similarly form a V-shape with puncturing layer 2162 due to the angle between elongate arms 2176a, 2176b.

[0376] The elongate arm 2176a may extend along the longitudinal axis of the cavity 2115. The elongate arm 2176a may extend from the piercing portion 2170 to the outer periphery 2126 of the housing 2114. In embodiments, the elongate arm 2176a may protrude from the outer periphery 2126 of the housing 2114, for example, as shown in FIG.

[0377] Figure 48C illustrates a cross-sectional view of the patch 2164 and housing 2114 along line CC shown in Figure 48A. The elongate arm 2176a of the puncture layer 2162 is shown extending along the cavity 2115. The space provided around the elongate arm 2176a can include a channel (marked in Figure 48A) that allows moisture to pass outward from the periphery 2126 of the housing 2114. The elongate arm 2176a can form a channel for removing moisture in a manner similar to that discussed with respect to the elongate arm 2176b in a portion 2180 of the elongate arm 2176a positioned outside the cavity 2115 (marked in Figure 48A).

[0378] The elongate arm 2176b may extend from the piercing portion 2170 to the outer periphery 2126 of the housing 2114. In embodiments, the elongate arm 2176b may protrude from the outer periphery 2126 of the housing 2114, for example, as shown in FIG. 48A.

[0379] FIG. 48D illustrates a cross-sectional view of patch 2164 and housing 2114 along line DD shown in FIG. 48A.

[0380] The elongate arms 2176b may further space the adhesive layer 2160 from the distal surface 2154 of the housing 2114 to form channels 2182 along the sidewalls 2184 of the puncture layer 2162. The channels 2182 may comprise gaps formed by the adhesive layer 2160 bending around the elongate arms 2176b and contacting the distal surface 2154 of the housing 2114. The channels 2182 may provide moisture passageways for removing moisture. The channels 2182 may transport moisture to the periphery 2126 of the housing 2114, for example, as shown in FIG. 48A .

[0381] In embodiments, one or more moisture passageways may be formed between the proximal surface 2186 of the puncture layer 2162 and the distal surface 2154 of the housing 2114. For example, the proximal surface 2186 of the puncture layer 2162 may lack adhesion to the distal surface 2154 of the housing 2114. Thus, moisture may be carried in the passageway between the proximal surface 2186 of the puncture layer 2162 and the distal surface 2154 of the housing 2114. The moisture passageways may extend along one or more of the elongate arms 2176a-2176e or ring portion 2174 shown in FIG. 48A.

[0382] The elongate arms 2176a, 2176b may extend laterally outward from the piercing portion 2170 to the outer periphery 2126 of the housing 2114. The elongate arm 2176c may extend longitudinally from the piercing portion 2170 along the housing 2114. The elongate arms 2176d, 2176e may be joined to the elongate arm 2176c and may be angled laterally relative to the elongate arm 2176c.

[0383] The elongate arm 2176d may extend into the cavity or recess 2133 of the housing 2114 or may protrude from the recess 2133 (as shown in FIG. 48A). The elongate arm 2176e may extend into the recess 2133 of the housing 2114 or may protrude from a circumferentially adjacent recess 2133 (as shown in FIG. 48A). The position of the elongate arms 2176d, 2176e protruding from the cavity or recess 2133 can aid in the removal of moisture from the distal end of the housing 2114.

[0384] Elongate arms 2176c, 2176d, 2176e may be configured to form one or more moisture passageways in a similar manner as elongate arm 2176b.

[0385] The configuration of channels emanating from the puncturing layer 2162 may allow for the removal of moisture proximate the insertion site of the transcutaneous analyte sensor into the skin. For example, moisture located at the puncturing portion 2170 may travel through the channels created by the elongated arms 2176a-2176e. This may result in a reduction in moisture accumulation at the insertion site and possible infection or other adverse consequences. Moisture may be removed in a direction toward the outer periphery 2126 of the housing 2114 (marked in FIG. 48A ). Moisture may include moisture located between the patch 2164 and the distal surface of the housing 2114.

[0386] The channel formed by the piercing layer 2162 may extend in a direction from a region 2178 of the patch 2164 proximate the site of insertion of the transcutaneous analyte sensor into the skin towards the periphery 2126 of the housing 2114 .

[0387] 48A-48D may be configured to wick moisture located distally of the housing 2114. The channels or moisture passages may have, for example, a geometry or other configuration that causes wicking. Wicking can transport moisture outside the perimeter 2126 of the housing 2114 for evaporation or other removal of the moisture from the vicinity of the system.

[0388] The configuration of the puncture layer 2162 may vary in embodiments. Figures 49A and 49B, for example, illustrate one embodiment in which an additional elongate arm 2176f may be utilized. The elongate arm 2176f may extend longitudinally relative to the housing 2114 and may be coupled to the puncture portion 2170. The elongate arm 2176f of the puncture layer 2188 may protrude from the periphery 2126 of the housing 2114. The elongate arm 2176f may be configured to form one or more moisture passageways in a manner similar to the elongate arm 2176b shown in Figure 48A.

[0389] Figure 50 illustrates an embodiment in which puncturing layer 2190 includes four elongate arms 2190a-2190d, which may be configured similarly to respective elongate arms 2176a, 2176c, 2176d, 2176e shown in Figure 48A.

[0390] 51 illustrates an embodiment in which the puncturing layer 2191 includes three elongate arms 2192a-2192c. The elongate arms 2192a, 2192b may be configured similarly to the respective elongate arms 2176a, 2176b shown in FIG. 48A. The elongate arm 2192c may extend longitudinally relative to the housing 2114 to the outer periphery 2126 of the housing 2114.

[0391] 52 illustrates an embodiment in which a single elongate arm 2194 may be utilized that may extend radially outward from the piercing portion 2171 to the outer periphery 2126 of the housing 2114. The elongate arm 2194 may be a straight elongate arm 2194 that may extend transversely or perpendicular to the longitudinal axis of the housing 2114. At least a portion of the elongate arm 2194 may overlap the cavity 2115. The elongate arm 2194 may be configured to provide one or more moisture passageways in a manner similar to that discussed with respect to the elongate arms 2176a, 2176b shown in FIG.

[0392] In embodiments, variations of notches or channels in the adhesive layer may be provided. Figure 53, for example, illustrates an embodiment in which an adhesive layer 2189 may be provided between a puncture layer (such as the puncture layer 2122 shown in Figure 47A) and a base layer (such as the base layer 2118 shown in Figure 47B). The adhesive layer 2189 may include a notch 2196 or channel that may extend longitudinally relative to the housing 2114 from the puncture portion 2136 to the outer periphery 2126 of the housing 2114. The notch 2196 may extend along the longitudinal axis of the housing 2114. The notch 2196 may form one or more moisture passageways, for example, in a manner similar to that discussed with respect to the notch shown in Figure 47F.

[0393] FIG. 54A illustrates a variation on the configuration of the notch 2134b shown in FIG. 47A. In the embodiment of FIG. 54A, the adhesive layer 2198 may include a notch 2200 that may overlap the elongated arm 2140 of the support portion 2138 shown in FIG. 47A. The notch 2200 may provide a channel distal to the elongated arm 2140 for moisture removal. The notch 2200 may extend from the piercing portion 2136 to the outer periphery 2126 of the housing 2114. FIG. 54B illustrates a cross-sectional view of the housing 2114 and patch 2202, for example, along line BB in FIG. 54A.

[0394] In embodiments, the notch in the adhesive layer 2204 may be spaced laterally from the piercing portion 2136. For example, Figure 55A illustrates the notch 2206 in the adhesive layer 2204 spaced laterally from the elongate arm 2140 shown, for example, in Figure 47A. Moisture may be transported from the cavity 2115 to the periphery 2126 of the housing 2114 in a manner similar to that discussed with respect to the channel shown, for example, in Figures 47C and 47D.

[0395] Figure 55B, for example, illustrates a cross-sectional view along line BB in Figure 55A. Figure 55C illustrates a cross-sectional view along line CC in Figure 55A.

[0396] FIG. 56 illustrates an embodiment without a puncture layer. The adhesive layer 2208 may include a laterally extending notch 2210 in a manner similar to the elongated arm 2194 shown in FIG. 52. The adhesive layer 2208 may include a notch 2212 extending longitudinally along the longitudinal axis of the housing 2114 and mating with the notch 2210. The notches 2210, 2212 may form a "T" shape. The notches 2210, 2212 may be configured to form a moisture passageway in a manner similar to that shown in FIG. 47F.

[0397] The moisture passageway configurations shown in Figures 46-56 may allow for the removal of moisture proximate the insertion site of the transcutaneous analyte sensor into the skin. For example, moisture located at the puncture site may be able to migrate through the moisture passageway, thus reducing the likelihood of moisture accumulation at the insertion site and possible infection or other adverse consequences. Moisture may be removed in a direction toward the periphery of the housing. In embodiments, moisture may include moisture located between the patch and the distal surface of the housing.

[0398] The moisture pathway may extend from a region of the patch adjacent the site of skin insertion of the transcutaneous analyte sensor toward the periphery of the housing.

[0399] In embodiments, one or more of the moisture passages may be configured to wick moisture located distally of the housing. The moisture passages may have, for example, a geometry or other configuration that results in wicking. Wicking can transport moisture outside the perimeter of the housing for evaporation or other removal of the moisture from the vicinity of the system.

[0400] In embodiments, a combination of one or more channels on the distal surface of the housing and one or more channels on the patch may be utilized, or one or more channels on the distal surface of the housing may be utilized alone, or one or more channels on the patch may be utilized alone.

[0401] The features of Figures 46-56 may be used alone or in combination with any method, system, or apparatus disclosed herein.

[0402] In embodiments, an antimicrobial agent may be coupled to at least a portion of the system. The system, in embodiments, may include an on-skin wearable medical device system. Referring to FIG. 57 , for example, the on-skin wearable medical device system may include a housing 2220, a patch 2222, and a transcutaneous analyte sensor 2224. The housing 2220 may be configured similarly to the housing 2010 shown in FIG. 40 unless otherwise noted. The patch 2222 may be configured similarly to the patch 1900 shown in FIG. 40 unless otherwise noted. The transcutaneous analyte sensor 2224 may be configured similarly to the transcutaneous analyte sensor 1920 shown in FIG. 40 unless otherwise noted. The system may include more or fewer components, as desired.

[0403] In embodiments, an antimicrobial agent may be positioned on at least a portion of the system to reduce the likelihood of the development or transmission of microorganisms or other pathogens either prior to application of the system to the recipient's skin or after application of the system to the recipient's skin. The antimicrobial agent may include at least a portion of a surface of one or more of the housing 2220, the transdermal analyte sensor 2224, or the patch 2222, or other components of the system.

[0404] For example, referring to FIG. 57 , the outer surface 2226 of the housing 2220 may include an antimicrobial agent. FIG. 57 shows a portion of the outer surface 2226 including a side 2228 having an antimicrobial agent applied thereto. Other portions of the outer surface 2226 (e.g., the proximal surface 2231) may have an antimicrobial agent applied thereto, if desired. In embodiments, the distal surface 2230 of the housing 2220, which faces the skin, may include an antimicrobial agent. A portion of the cavity 2232 may include an antimicrobial agent. For example, the surface of the insertion channel 2234 may include an antimicrobial agent. Such a location may reduce the likelihood of microorganisms or other pathogens being positioned proximate to the insertion side of the sensor 2224 into the recipient's skin. In embodiments, the inner surface of the housing 2220 may include an antimicrobial agent.

[0405] The portion of the housing 2220 proximate the site of insertion of the transcutaneous analyte sensor into the skin may include an antimicrobial agent.

[0406] At least a portion of the patch 2222 may include an antimicrobial agent. For example, the first or distal surface 2236 of the patch 2222 for engaging the skin may include an antimicrobial agent. A region of the distal surface 2236 proximate the insertion site of the sensor 2224 into the skin may include an antimicrobial agent to reduce the likelihood of microorganisms or other pathogens being positioned at an entry site into the recipient's skin. In embodiments, the puncturing layer 2238 of the patch 2222 may include an antimicrobial agent. Such a location may reduce the likelihood of such pathogens being positioned at an entry site into the recipient's skin. Furthermore, such a location may reduce the likelihood of such pathogens migrating to the sensor 2224. In embodiments, the proximal surface 2240 of the patch 2222 may include an antimicrobial agent. The proximal surface 2240 may face the distal surface 2230 of the housing 2220, opposite the distal surface 2230 of the housing 2220. The antimicrobial agent may be bonded to the adhesive that bonds the patch 2222 to the housing 2220 .

[0407] The portion of patch 2222 adjacent the site of insertion of the analyte sensor into the skin may include an antimicrobial agent.

[0408] In embodiments, patch 2222 may include a skirt 2242 that may be positioned radially outward of outer periphery 2244 of housing 2220. In embodiments, an antimicrobial agent may be coupled to a portion of skirt 2242. Various portions of patch 2222 or components of the patch may include an antimicrobial agent.

[0409] In embodiments, at least a portion of the transcutaneous analyte sensor 2224 may include an antimicrobial agent. For example, an exterior surface that may be inserted into the skin or another part of the recipient may include an antimicrobial agent.

[0410] The antimicrobial agent may be applied to a portion of the system as a surface coating or may be otherwise applied to the system. The antimicrobial agent may have a variety of forms, including one or more of iodine, silver, or chlorhexidine gluconate, among others.

[0411] In embodiments, the antimicrobial agent may comprise an antimicrobial adhesive, which may be utilized with any of the adhesives disclosed herein, such as, for example, an adhesive for adhering to the skin of a recipient or an adhesive for bonding the patch to a housing, among other uses.

[0412] Antimicrobial agents may be utilized with any of the systems disclosed herein.

[0413] Patches for use with the system can have a variety of forms. For example, in embodiments, the patch may extend radially outward from the outer periphery of the housing to form a skirt. Figure 57, for example, illustrates patch 2222 radially outward from outer periphery 2244 of housing 2220, forming skirt 2242.

[0414] However, in embodiments, the patch may not extend outward from the outer periphery of the housing. Referring to FIG. 58 , for example, the patch 2250 can have the same radial extent as the housing 2252. The housing 2252 may be configured similarly to the housing 2010 shown in FIG. 40 unless otherwise noted. The housing 2252 may have, for example, an outer periphery 2254, and the outer periphery 2256 of the patch 2250 may extend to the outer periphery 2254 of the housing 2252. The shape of the outer periphery 2256 of the patch 2250 may match the shape of the outer periphery 2254 of the housing 2252.

[0415] In embodiments, the outer periphery 2258 of the patch 2260 may be recessed from the outer periphery 2254 of the housing 2252. FIG. 59, for example, illustrates such a configuration. The circumferential buffer region 2263 may extend around the patch 2260 and may be positioned between the outer periphery 2258 of the patch 2260 and the outer periphery 2254 of the housing 2252.

[0416] The features of the patches 2250, 2260 shown in Figures 58 and 60 may be utilized alone or in conjunction with any of the methods, devices, or systems disclosed herein.

[0417] In embodiments, the patch may be coupled to the housing solely with adhesive. For example, FIG. 60 illustrates a schematic cross-sectional view of a patch 2262 coupled to a housing 2264. The housing 2264 may be configured similarly to the housing 2010 shown in FIG. 40 unless otherwise noted. The patch 2262 may be coupled solely to the housing 2264 using adhesive, for example, to the distal surface 2266 of the housing 2010. The patch 2262 can be coupled to the housing 2010 in a variety of ways.

[0418] For example, an adhesive can be applied to the proximal surface 2268 of the patch 2262 to adhere the proximal surface 2268 to the distal surface 2266 of the housing 2264. The adhesive may be positioned between the patch 2262 and the distal surface 2266 of the housing 2264. The adhesive, in embodiments, may extend over the entire surface area of ​​the distal surface 2266 or only a portion of the surface area. In embodiments, the patch 2262 may include multiple layers, and the adhesive layer 2270 is sandwiched between the proximal surface 2272 of the base layer 2274 of the patch 2262 and the distal surface 2266 of the housing 2264. The adhesive layer 2270 may include a distal surface 2276 that may adhere to the proximal surface 2272 of the base layer 2274.

[0419] 61, for example, illustrates a schematic cross-sectional view of patch 2262 with base layer 2274 shown separated from adhesive layer 2270. Adhesive layer 2270 may include one or more sublayers as desired. For example, adhesive layer 2270 may include a carrier sublayer 2280 that may be sandwiched between a proximal adhesive sublayer 2282 and a distal adhesive sublayer 2284. Proximal adhesive sublayer 2282 may be adhered to distal surface 2266 (marked in FIG. 60) of housing 2264. Distal adhesive sublayer 2284 may be adhered to proximal surface 2272 of base layer 2274. Carrier sublayer 2280 may be breathable in embodiments. Carrier sublayer 2280 can include a material such as polyethylene or another material as desired.

[0420] The base layer 2274 may include a backing or backing sublayer 2286 and may include an adhesive or skin adhesive sublayer 2288 positioned distally of the backing sublayer. The backing sublayer 2286 may be made from a material such as a nonwoven material, among others. Such nonwoven materials may include nonwoven polyester or nonwoven polyurethane, among others.

[0421] The adhesive layer 2270 may extend over the entire distal surface 2266 of the housing 2264 (as marked in FIG. 60) or may extend over only a portion of the distal surface 2266.

[0422] The base layer 2274 may protrude from the periphery 2290 of the housing 2264 to form a skirt 2292, for example, as shown in FIG. 60. Thus, the backing sublayer 2286 may comprise the proximal surface of the patch 2262 outside the housing 2264. In embodiments, the patch 2262 may not extend outside the periphery 2290 of the housing 2264, as shown in FIG. 58, or may be recessed from the periphery 2290 of the housing, as shown in FIG. 59.

[0423] The sole use of adhesive to bond patch 2262 to housing 2264 can provide various advantages. For example, it can result in reduced complexity in manufacturing an on-skin wearable medical device. Methods such as heat staking or other forms of mechanical or frictional attachment of the patch to the housing can be eliminated if desired. Furthermore, it can result in increased retention between patch 2262 and housing 2264.

[0424] In embodiments, a method may include manufacturing an on-skin wearable medical device in which a patch is attached only with an adhesive. The method may include providing a housing. The method may include providing a patch, which may have an adhesive surface in a manner disclosed herein. The adhesive surface may be applied to the patch, or an adhesive layer may be formed that may include the adhesive surface. For example, adhesive layer 2270 may be fabricated as shown in FIG. 61 , which may include one or more adhesive sublayers for bonding to the housing (and to base layer 2274). Base layer 2274 may be fabricated. Base layer 2274 may be adhered to adhesive layer 2270, which may be adhered to distal surface 2266 of housing 2264. Patch 2262 may be pressed against distal surface 2266 of housing 2264 until the adhesive cures.

[0425] Steps in the method may be rearranged, eliminated, or added as desired.

[0426] In embodiments, the backing sublayer 2286 may comprise a proximal surface of the patch 2262 outside the housing 2264 (e.g., skirt 2292 shown in FIG. 60 ). In embodiments, an additional layer may be provided over the backing sublayer 2286 to form an overlay thereon. The overlay may form a skirt positioned radially outward of the outer periphery of the housing. For example, with reference to FIG. 62 , the base layer 2274 may be replicated and adhered to itself to form an overlay 2300 over the backing sublayer 2286. The overlay 2300 may include a sublayer 2302 that may include a replica of the skin adhesive sublayer 2288. The sublayer 2302 may be adhered to the proximal surface of the backing sublayer 2286. The overlay 2300 may include a sublayer 2304 that may include a replica of the backing sublayer 2286. The sublayer 2304 may comprise the proximal surface of the assembled patch 2306 shown in Figure 62. In an embodiment, the overlay 2300 can surround the exposed portion 2308 of the patch 2262 that does not include the overlay 2300, and the backing sublayer 2286 comprises the proximal surface of the patch 2262.

[0427] In embodiments, the overlay 2300 may be cut to match the shape of the outer periphery of the housing. For example, FIG. 63 illustrates a top view of the patch 2306 shown in FIG. 62. The overlay 2300 is shown cut to create an exposed portion 2308 having the shape of the outer periphery of the housing. The patch 2306 may be applied to the distal surface of the housing, with the overlay 2300 forming a skirt that extends radially outward from the housing.

[0428] The materials that may comprise the patch may vary in embodiments. For example, referring to FIG. 64, patch 2310 may optionally include multiple perforations 2312. FIG. 65, for example, illustrates a distal view of the on-skin wearable medical device shown in FIG. 64, where the positioning of the perforations may vary (e.g., longitudinally aligned perforations and laterally aligned perforations 2314). Perforations may be utilized to improve the breathability of the patches disclosed herein.

[0429] 66 illustrates an embodiment in which the patch 2320 may include a scrim. The patch 2320 may include a plurality of openings 2322 formed by the scrim, which may improve the breathability of the patch 2320. In embodiments, the patches disclosed herein may include a skirt or may not extend outside the perimeter of the housing, for example, as depicted in FIGS.

[0430] The features of Figures 58-66 may be used alone or in conjunction with any method, system, or apparatus disclosed herein.

[0431]

[00110] Embodiments of the liner removal component disclosed herein may include a sheath that may cover at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. The sheath may include one or more openings that may allow exposure to the environment within the applicator housing. For example, referring to Figure 27A, the sheath 1010 may include multiple openings for exposing the insertion element 915 or the transcutaneous analyte sensor to any sterilizing substance, such as a sterilizing gas, that may be utilized and positioned within the cavity 903 of the applicator housing.

[0432] In embodiments, the sheath may seal at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. For example, FIG. 67 illustrates a distal perspective view of a liner removal component 2330 including a sheath 2332 for sealing at least a portion of the needle or at least a portion of the transcutaneous analyte sensor. The liner removal component 2330 may be configured similarly to the embodiments of liner removal components disclosed herein unless otherwise noted.

[0433] FIG. 68 illustrates a schematic cross-sectional view of the liner removal component 2330 shown in FIG. 67. The sheath 2332, unlike the embodiment shown in FIG. 27A, lacks openings around the insertion element 915 and the transcutaneous analyte sensor 1920. Thus, the sheath 2332 can prevent sterilizing gas or other substances from contacting the insertion element 915 or the transcutaneous analyte sensor 1920. Furthermore, the binding surface 2334 may form a ring around the opening 2336 through which the insertion element 915 and the transcutaneous analyte sensor 1920 extend. Such binding surface 2334 may further seal an internal cavity 2338 that is surrounded by the sheath 2332 and receives the insertion element 915 and the transcutaneous analyte sensor 1920. The needle hub 2340 can include a sealing member, such as a gasket 2342, configured to seal the internal cavity 2338. The gasket may comprise an O-ring in embodiments, or may have other configurations. Embodiments such as that shown in Figure 68 may be sterilized by non-gas methods, such as e-beam sterilization or other non-contact sterilization methods.

[0434] The liner removal component 2330 may be removed at a desired time to break the seal of the interior cavity 2338 and allow insertion of the insertion element 915 and transcutaneous analyte sensor 1920 into the skin.

[0435] In embodiments, at least a portion of the sheath may include a layer configured to allow sterilizing gas to permeate therethrough and contact at least a portion of the insertion element 915 or at least a portion of the transcutaneous analyte sensor 1920. For example, with reference to FIG. 69 , layer 2344 may be provided over opening 2346 in sheath 2348, which may otherwise be configured similarly to sheath 2332 shown in FIG. 68. Layer 2344 may include a gas permeable layer, such as Tyvek or other form of gas permeable material, that may allow access to interior cavity 2338 for sterilization of at least a portion of the insertion element 915 or at least a portion of the transcutaneous analyte sensor 1920.

[0436] Figure 70 illustrates a variation of the embodiment shown in Figure 69 in which a bonding surface 2350, such as an adhesive, may be utilized to seal the connection between the on-skin sensor assembly 508 and the needle hub 914 and to seal the internal cavity 2338. Thus, the gasket 2342 shown in Figure 68 or 69 may be replaced by another form of sealing element.

[0437] FIG. 71 illustrates an embodiment of a liner removal component 2360 including an engagement portion 2362 configured to engage an outer surface of the applicator housing 2364 to retain the liner removal component 2360 to the applicator housing 2364. The engagement portion 2362 may be configured to disengage from the outer surface of the applicator housing 2364 when the liner removal component 2360 is pulled axially relative to the applicator housing 2364. For example, the engagement portion 2362 may comprise a press fit or friction fit with the applicator housing 2364. The engagement portion 2362 may include a snap or compression engagement with the applicator housing 2364. The liner removal component 2360 may be pulled axially from the applicator housing 2364 without rotating the liner removal component 2360. Thus, features such as threading and unthreading may be eliminated. The liner removal component 2360 may be pulled axially for removal, or may be pushed axially to reconnect with the applicator housing 2364, if desired.

[0438] In embodiments, the sheath 2366 of the liner removal component may be configured similarly to the sheath 2348 shown in, for example, Figures 69 and 70. The sheath 2366 may seal an interior cavity 2368. A layer 2670 may be applied to the sheath 2366 which may seal an opening 2372 in the sheath 2366 and may be gas permeable in a manner similar to layer 2344.

[0439] In embodiments, a stabilizer 2374 can be provided that can stabilize the transcutaneous analyte sensor 1920 within the channel of the insertion element 915. The stabilizer 2374 may comprise, for example, a pin that can be removed along with removal of the liner removal component 2360 from the applicator housing 2364 or otherwise from the on-skin sensor assembly 508.

[0440] In embodiments, other forms of stabilizers may be utilized. For example, FIG. 72 illustrates an embodiment in which an O-ring 2376 surrounding the insert element 915 may be utilized as a stabilizer. The O-ring 2376 may be removed along with removal of the liner removal component 2378 from the applicator housing or otherwise from the on-skin sensor assembly 508.

[0441] 73 illustrates an embodiment of a liner removal component 2380 that shields an optical sensor 2382 of an on-skin wearable medical device or on-skin sensor assembly from light. The liner removal component 2380 may include a light shield 2384, which may be opaque or otherwise block the type of light that the optical sensor 2382 is configured to receive, for example. The liner 2386, or one or more layers of the patch 2388, may include an opening to expose the optical sensor 2382 to light.

[0442] The sensor 2382 may be configured to activate or perform a wake-up operation for the on-skin sensor assembly. For example, the on-skin sensor assembly may be held in a low power state until activated by exposure of the optical sensor 2382 to light. In a storage or transport configuration, the liner removal component 2380 may be coupled to the patch 2388 via the liner 2386. The shield 2384 may block reception of light by the optical sensor 2382 in such a storage or transport configuration.

[0443] At a desir...

Claims

1. 1. A system comprising: an on-skin wearable medical device configured to be placed on the skin and including a patch having a first surface for engaging the skin; a liner positioned on the first surface; an applicator housing configured to hold the wearable medical device on the skin; a liner removal component configured to engage the liner and to at least partially separate the liner from the first surface when the liner removal component is at least partially withdrawn from the first surface.

2. The system of claim 1 , wherein the applicator housing is configured to be grasped by a user.

3. The system of claim 1 , further comprising one or more retention elements for releasing the on-skin wearable medical device from the applicator housing.

4. The system of claim 1 , further comprising an insertion assembly for inserting at least a portion of the on-skin wearable medical device into the skin.

5. The system of claim 4 , wherein the insertion assembly includes at least one spring for inserting at least a portion of the on-skin wearable medical device into the skin.

6. The system of claim 4 , wherein the insertion assembly is configured to insert a needle into the skin.

7. The system of claim 6 , further comprising a retraction assembly for retracting the needle from the skin.

8. The system of claim 1 , wherein the applicator housing includes an internal cavity for holding the on-skin wearable medical device.

9. The system of claim 8 , wherein the liner removal component includes a body configured to extend axially within the internal cavity.

10. The system of claim 9 , wherein the applicator housing includes an opening at an end portion of the internal cavity for placement of the on-skin wearable medical device.

11. The system of claim 10 , wherein the liner removal component includes a first portion for engaging the liner and a second portion axially spaced from the first portion.

12. The system of claim 11 , wherein the second portion is configured to be positioned in the opening.

13. 12. The system of claim 11, wherein the applicator housing includes a distal end portion and a proximal end portion, the opening is positioned at the distal end portion of the applicator housing, and at least a portion of the liner removal component is configured to extend outside the applicator housing from the second portion to a third portion positioned at the proximal end portion of the applicator housing.

14. The system of claim 13 , wherein the liner removal component includes an opening in the third portion configured to pass the applicator housing therethrough.

15. The system of claim 14 , further comprising a cover positioned in the opening of the third portion to cover the applicator housing.

16. The system of claim 1 , wherein the liner removal component includes a first portion for engaging the liner and a second portion spaced from the first portion.

17. The system of claim 16 , wherein the second portion is configured to be unthreaded from the applicator housing to at least partially separate the liner removal component from the applicator housing.

18. 17. The system of claim 16, wherein the liner removal component includes one or more guides configured to prevent the first portion from rotating relative to the applicator housing when the second portion rotates relative to the first portion.

19. 20. The system of claim 18, wherein the one or more guides are configured to engage an inner surface of the applicator housing to prevent the first portion from rotating relative to the applicator housing.

20. 17. The system of claim 16, wherein the liner removal component includes one or more rotary couplers spaced apart from one or more bearing surfaces by a gap, the one or more rotary couplers configured to rotate relative to the one or more bearing surfaces.

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