Microneedle enclosures and applicator devices for microneedle array-based continuous analyte monitoring devices

Abstract

An applicator for an analyte monitoring device may include an actuatable housing having a body defining a cavity therein and having a distal opening and a side opening. The ferrule and the transfer member are received within the cavity and are individually movable relative to the housing body. The base may removably engage the housing body at the distal opening. The housing body, the ferrule, the transfer member, and / or the base may be engaged with each other using one or more releasable coupling features. The base is disengageable from engagement with the housing body causing the ferrule and the transfer member to align and position in a configuration in which the analyte monitoring device held by the transfer member is ready for insertion into the skin.

Description

[0001] This application is a divisional application of the application patent application with the application number 202280025786.5, the title of “Microneedle encasement and applicator device for a microneedle array-based continuous analyte monitoring device”, and the filing date of September 27, 2022.

[0002] Cross Reference to Related Applications

[0003] This application claims priority to U.S. Provisional Patent Application No. 63 / 249,399, filed September 28, 2021, U.S. Provisional Patent Application No. 63 / 291,293, filed December 17, 2021, and U.S. Provisional Patent Application No. 63 / 355,987, filed June 27, 2022, the contents of which are incorporated by reference in their entirety. TECHNICAL FIELD

[0004] The present invention relates generally to the field of analyte monitoring, such as continuous glucose monitoring. BACKGROUND

[0005] Diabetes is a chronic disease in which the body cannot produce or properly utilize insulin, a hormone that regulates blood glucose. Diabetics can be administered insulin to help regulate blood glucose levels, yet blood glucose levels must still be carefully monitored to help ensure that timing and dosage are appropriate. If their condition is not properly managed, diabetics can suffer from a variety of complications resulting from hyperglycemia (high blood glucose levels) or hypoglycemia (low blood glucose levels).

[0006] Blood glucose monitors help diabetics manage their condition by measuring blood glucose levels in a blood sample. For example, a diabetic can obtain a blood sample by finger prick, transfer the blood sample to a test strip having suitable reagents that react with the blood sample, and analyze the test strip using a blood glucose monitor to measure the glucose level in the blood sample. However, a patient using this procedure can typically only measure his or her glucose level at discrete moments in time, which can not timely capture hyperglycemic or hypoglycemic conditions. A newer type of glucose monitor is a continuous glucose monitoring (CGM) device, which includes a percutaneously implantable electrochemical sensor that is used to continuously detect and quantify blood glucose levels through surrogate measurement of glucose levels in the interstitial fluid beneath the skin. However, traditional CGM devices also have weaknesses, including tissue damage from insertion and signal delay (e.g., due to the time required for diffusion of glucose analyte from capillary sources to the sensor). These weaknesses also result in a number of drawbacks, such as pain experienced by the patient when the electrochemical sensor is inserted, and limited accuracy of glucose measurements, especially when blood glucose levels are rapidly changing. Thus, there is a need for a new and improved analyte monitoring system. SUMMARY

[0007] According to one embodiment, the present application relates to analyte monitoring.

[0008] In various embodiments, the present application also relates to an applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, wherein the housing body comprises a distal opening; a collar received within the cavity and comprising a lumen therethrough; and a carrier slidably received within the lumen and configured to releasably retain the analyte monitoring device, wherein the applicator is movable between a retracted configuration in which the analyte monitoring device is retained within the carrier and the distal edge of the collar and the carrier are in a proximal-most position, an extended configuration in which the distal edge of the collar is in a distal-most position and the carrier is in an intermediate position, and a released configuration in which the analyte monitoring device is released from the carrier, the distal edge of the collar is in an intermediate position, and the carrier is in a distal-most position.

[0009] In various embodiments, the present application also relates to an applicator for an analyte monitoring device, the applicator comprising: a housing comprising a body defining a cavity therein, wherein the housing body comprises a distal opening; a collar received within the cavity and comprising a lumen therethrough; and a carrier slidably received within the lumen and configured to releasably retain the analyte monitoring device, wherein the applicator is movable between a retracted configuration in which the analyte monitoring device is retained within the carrier, the distal edge of the collar and the carrier are positioned proximal of the distal opening of the housing body, an extended configuration in which the distal edge of the collar is positioned distal of the distal opening of the housing body and the carrier is positioned proximal of the distal opening of the housing body, and a released configuration in which the analyte monitoring device is released from the carrier, the distal edge of the collar is distal of the distal opening of the housing body, and the carrier is distal of the distal opening of the housing body.

[0010] In various embodiments, the present invention is also directed to a method of applying an analyte monitoring device to a skin surface of a user, the method comprising: providing an applicator in a collapsed configuration, wherein the applicator comprises a delivery member releasably retaining an analyte monitoring device, the delivery member slidably received within a trigger cavity of a cuff, the cuff received within a cavity of a housing, the housing comprising a body defining the cavity, the housing body comprising a distal opening; transitioning the applicator from the collapsed configuration to an extended configuration; and transitioning the applicator from the extended configuration to a release configuration, wherein in the collapsed configuration, a distal edge of the cuff and the delivery member are in a proximal-most position, in the extended configuration, the distal edge of the cuff is in a distal-most position and the delivery member is in an intermediate position, and in the release configuration, the analyte monitoring device is released from the delivery member and the distal edge of the cuff is in the intermediate position and the delivery member is in the distal-most position.

[0011] In various embodiments, the present invention is also directed to an applicator for an analyte monitoring device, the applicator comprising: a. a housing comprising a body defining a cavity therein, wherein the housing body comprises a distal opening and a side opening; b. a cuff received within the cavity; c. a delivery member received within the cavity configured to releasably retain the analyte monitoring device; d. a locking member at least partially received in the side opening of the housing body, wherein the locking member is in engagement with the cuff in a first configuration and out of engagement with the cuff in a second configuration; and e. a base configured to be removably coupled to the housing body at the distal opening of the housing body, wherein the base comprises a proximal surface, f. wherein movement of the locking member from the first configuration to the second configuration releases the cuff such that the proximal surface is decoupled from the housing body.

[0012] In various embodiments, the present invention is also directed to a method of using an applicator for an analyte monitoring device, the method comprising: transitioning a locking member of the applicator from a first configuration to a second configuration, wherein the applicator comprises a housing body defining a cavity therein, a cuff and a delivery member each received within the cavity, and a base removably coupled to the housing body, wherein the delivery member releasably retains the analyte monitoring device, wherein transitioning the locking member disengages the locking member from the cuff, thereby allowing the cuff to move relative to the housing body; and moving the base of the applicator relative to the housing body.

[0013] In various embodiments, the present invention is also directed to an applicator for an analyte monitoring device, the applicator comprising a housing comprising a body defining a cavity therein, a ferrule received within the cavity and comprising a lumen, and a delivery member received within the lumen, wherein the delivery member comprises a shaft and a base portion at a distal end of the shaft, wherein the base portion comprises a plurality of flexible vanes extending from the shaft and a plurality of petals extending from the shaft, and wherein the plurality of flexible vanes define a receptacle for holding the analyte monitoring device.

[0014] In various embodiments, the present invention is also directed to an applicator for an analyte monitoring device, the applicator comprising a housing comprising a housing body and a mount, a ferrule-ring assembly comprising a ferrule and a friction ring coupled to the ferrule, and a delivery member configured to releasably hold the analyte monitoring device, wherein the delivery member and the ferrule-ring assembly are individually translatable relative to the housing body, wherein the delivery member and the ferrule-ring assembly are each releasably coupled to the mount.

[0015] In various embodiments, the present invention is also directed to an applicator for an analyte monitoring device, the applicator comprising a housing comprising a housing body defining a cavity therein and a mount extending into the cavity from an inner surface of a proximal end of the housing body, a ferrule-ring assembly comprising a ferrule having a lumen and a proximal opening and a friction ring positioned in the lumen and extending through the proximal opening, wherein the ferrule-ring assembly is seated about the mount, and a delivery member configured to releasably hold the analyte monitoring device, wherein a portion of the delivery member extends through the mount.

[0016] In various embodiments, the present invention is also directed to an applicator for an analyte monitoring device, the applicator comprising a housing comprising a housing body defining a cavity therein and a mount extending into the cavity, a ferrule-ring assembly comprising a ferrule and a friction ring coupled to the ferrule, a delivery member configured to releasably hold the analyte monitoring device, and a base removably coupled to the housing, wherein the mount is configured to 1) releasably engage the friction ring to prevent axial movement of the delivery member prior to removal of the base from the housing and 2) releasably engage the delivery member to control axial movement of the delivery member after removal of the base from the housing.

[0017] In various embodiments, the present disclosure is also directed to. In various of the schemes, the present disclosure is also directed to a method of applying an analyte monitoring device to a skin surface using an applicator, the method comprising: providing an applicator comprising a housing defining a cavity, a collar, and a carrier, wherein the collar and the carrier are each received within the cavity, wherein the carrier holds the analyte monitoring device; applying a distal surface of the collar of the applicator to the skin surface; advancing the housing toward the skin surface, wherein advancing the housing moves the housing relative to the collar and the carrier, and disengages one or more retention features that prevent the carrier from moving independently of the housing, wherein disengagement of the one or more retention features releases the carrier, and advances the carrier with the analyte monitoring device toward the skin surface; and releasing the analyte monitoring device from the carrier.

[0018] In various embodiments, the present disclosure is also directed to an applicator for an analyte monitoring device, the applicator comprising: a housing comprising a main body defining a cavity therein and defining a distal opening; a collar slidably received within the cavity and comprising a lumen therethrough; a carrier slidably received within the lumen and configured to releasably hold an analyte monitoring device; a first biasing element disposed between the housing and the collar; a second biasing element disposed between the housing and the carrier; a microneedle capsule releasably engaged with the analyte monitoring device and configured to encapsulate a portion of the analyte monitoring device when engaged, the microneedle capsule comprising a third biasing element; and a base releasably engaged with the housing and coupled to the microneedle capsule. BRIEF DESCRIPTION OF DRAWINGS

[0019] FIG. 1 A schematic of an analyte monitoring system with a microneedle array is depicted.

[0020] FIG. 2A A schematic of an analyte monitoring device is depicted.

[0021] FIG. 2B A schematic of a microneedle insertion depth in an analyte monitoring device is depicted.

[0022] FIG. 3A-3D An upper perspective view, a side view, a bottom view, and an exploded view of an analyte monitoring device are respectively depicted.

[0023] FIG. 4A-4E A perspective exploded view, a side exploded view, a lower perspective view, a side view, and an upper perspective view of a sensor assembly in an analyte monitoring device are respectively depicted.

[0024] FIG. 4F-4H A perspective exploded view, a side exploded view, and a side view of a sensor assembly in an analyte monitoring device are respectively depicted.

[0025] FIG. 5A-5D Aspects of a microneedle enclosure are depicted in the form of exploded perspective, first side and side sectional view, second side and side sectional view, and bottom perspective views, respectively.

[0026] FIG. 5E-5G Aspects of a microneedle enclosure and a substrate of an analyte monitoring device are depicted in the form of perspective exploded view, perspective view, and side sectional view, respectively.

[0027] FIG. 6A A schematic diagram of a microneedle array is depicted. FIG. 6B A schematic diagram of a microneedle array is depicted. FIG. 6A A schematic diagram of a microneedle array is depicted.

[0028] FIG. 7 A schematic diagram of a microneedle array for detecting multiple analytes is depicted.

[0029] FIG. 8A A side sectional view of a cylindrical microneedle having a tapered distal end is depicted. FIG. 8B A side sectional view of a cylindrical microneedle having a tapered distal end is depicted. 8C A perspective view and a detailed view of one embodiment of a microneedle are depicted, respectively. FIG. 8A A perspective view and a detailed view of one embodiment of a microneedle are depicted, respectively.

[0030] FIG. 9 A schematic diagram of a cylindrical microneedle having a tapered distal end is depicted.

[0031] FIG. 10A A schematic diagram of a microneedle array and a microneedle are depicted, respectively. 10B A schematic diagram of a microneedle array and a microneedle are depicted, respectively. FIG. 10C-10F A detailed partial view of an exemplary variation of a microneedle is depicted.

[0032] FIG. 11A A detailed partial view of an exemplary variation of a microneedle is depicted. 11B A detailed partial view of an exemplary variation of a microneedle is depicted.

[0033] FIG. 12A A schematic diagram of a microneedle array configuration is depicted. 12B A schematic diagram of a microneedle array configuration is depicted. FIG. 12C A schematic diagram of a microneedle array configuration is depicted. 12D A schematic diagram of a microneedle array configuration is depicted.

[0034] FIG. 13A A perspective view and an orthogonal view of an exemplary variation of a carrier sheet comprising a microneedle array are depicted, respectively. 13B A perspective view and an orthogonal view of an exemplary variation of a carrier sheet comprising a microneedle array are depicted, respectively.

[0035] FIG. 14A-14J A schematic diagram of different variations of a microneedle array configuration is depicted.

[0036] FIG. 15A-15DAspects of an applicator for an analyte monitoring device are depicted in a first side view, a second side view, a top perspective view, and a bottom perspective view, respectively.

[0037] FIG. 15E and FIG. 15F Aspects of an analyte monitoring device relative to an applicator delivery member are depicted in exploded view and perspective view, respectively.

[0038] FIG. 16A-16D Aspects of a delivery member of an applicator for an analyte monitoring device are depicted in top perspective view, bottom view, side view, and side cutaway view, respectively.

[0039] FIG. 16E and 16F Aspects of a delivery member of an applicator for an analyte monitoring device are depicted in bottom perspective view and bottom view, respectively.

[0040] FIG. 16G and 16H Aspects of a delivery member of an applicator for an analyte monitoring device are depicted in side view and side cutaway view, respectively.

[0041] FIG. 17A-17E Aspects of a ferrule of an applicator for an analyte monitoring device are depicted in top perspective view, bottom view, top view, first side and side cutaway view, and second side and side cutaway view, respectively.

[0042] FIG. 17F and FIG. 17G Aspects of a ferrule of an applicator for an analyte monitoring device are depicted in bottom view and side view, respectively.

[0043] FIG. 18A-18D Aspects of a locking friction ring of an applicator for an analyte monitoring device are depicted in first top perspective view, second top perspective view, first bottom perspective view, and second bottom perspective view, respectively.

[0044] FIG. 19A-19E Aspects of a ferrule-ring assembly of an applicator for an analyte monitoring device are depicted in top perspective view, bottom view, top view, side view, and side cutaway view with detailed view, respectively.

[0045] FIG. 20A-20F Aspects of a housing of an applicator for an analyte monitoring device are depicted in first top perspective view, second top perspective view, first bottom perspective view, second bottom perspective view, first side cutaway view, and second side cutaway view, respectively.

[0046] FIG. 21A-21B Aspects of a locking member of an applicator for an analyte monitoring device are depicted in front perspective view and back perspective view, respectively.

[0047] FIG. 22A-22G Aspects of a base of an applicator for an analyte monitoring device are depicted in top perspective view, top view, bottom view, first side view, first side cutaway view, second side view, and second side cutaway view, respectively.

[0048] FIG. 22H-22J Aspects of an applicator base of an analyte monitoring device having a microneedle enclosure are depicted in exploded view, top perspective view, and side cutaway view, respectively.

[0049] FIG. 22K Aspects of a base of an applicator for an analyte monitoring device engaged with a cuff of the applicator are depicted in top perspective view.

[0050] FIG. 23A-23O Views of an applicator for an analyte monitoring device in a variety of different configurations are depicted in cutaway view and close-up view.

[0051] FIG. 24 A process flow diagram to illustrate the process of an applicator from a collapsed configuration to an extended configuration.

[0052] FIG. 25 A process flow diagram to illustrate the process from an extended configuration to a released configuration of an applicator.

[0053] FIG. 26A and FIG. 26B Views of an applicator for an analyte monitoring device in a variety of different configurations are depicted in cutaway view and close-up view.

[0054] FIG. 27A-27C Upper perspective view, side view, and lower perspective view of an analyte monitoring device are depicted, respectively. FIG. 27D A partial exploded view of an analyte monitoring device including an adhesive layer is depicted. FIG. 27A A partial exploded view of an analyte monitoring device as shown in FIG. FIG. 27E A partial exploded view of an analyte monitoring device as shown in FIG. FIG. 27A A partial exploded view of an analyte monitoring device as shown in FIG.

[0055] FIG. 27F-27I Upper perspective view, lower perspective view, side view, and exploded view of a sensor assembly in an analyte monitoring device are depicted, respectively.

[0056] FIG. 27J A transparent side view of a sensor assembly in an analyte monitoring device is depicted.

[0057] FIG. 28A-28E Perspective view, side view, bottom view, side cutaway view, and upper transparent perspective view of an analyte monitoring device are depicted, respectively.

[0058] FIG. 29A side cutaway view of a cylindrical microneedle having a tapered distal end is depicted.

[0059] FIG. 30 A schematic view of a cylindrical microneedle having a tapered distal end is depicted.

[0060] FIG. 31A-31C An upper perspective view, a side view, and a lower perspective view of an applicator are depicted, respectively. FIG. 31D A perspective view of an applicator is depicted in FIG. 31A-31C An exploded view of the applicator shown in

[0061] FIG. 32A-32G An upper perspective view, a lower perspective view, another upper perspective view, another lower perspective view, a top view, a side view, and a bottom view of an applicator delivery member are depicted, respectively.

[0062] FIG. 33A-33E An upper perspective view, a top view, a bottom view, a side view, and a lower perspective view of an applicator trigger are depicted, respectively. FIG. 33F A perspective view of a trigger is depicted in FIG. 33A-33E Another side view of the trigger shown in FIG. 33G A cutaway view of the trigger is depicted along FIG. 33F line 18G: 18G in

[0063] FIG. 34A An upper perspective view of an applicator housing is depicted. FIG. 34B-34F An upper perspective view, a top view, a bottom view, a side view, and a lower perspective view of a housing are depicted, respectively. FIG. 34A An upper perspective view, a top view, a bottom view, a side view, and a lower perspective view of the housing shown in FIG. 34G A side cutaway view of the housing is depicted along FIG. 34F line 19G: 19G in

[0064] FIG. 34H and 34I An example variation of an applicator housing is depicted.

[0065] FIG. 35A A bottom view of an applicator at the beginning of a loading process to load an analyte monitoring device into the applicator is depicted. FIG. 35B A bottom view of the applicator after the analyte monitoring device has been loaded into the applicator is depicted in FIG. 35A A bottom view of the applicator after the analyte monitoring device has been loaded into the applicator is depicted in

[0066] FIG. 36A-36C A loading process to load an analyte monitoring device into an applicator is depicted.

[0067] FIG. 37A , 37B and 37D depict a cutaway view of an applicator in a loaded configuration for deploying an analyte monitoring device from the applicator. FIG. 37C A perspective view of an applicator is depicted in FIG. 37Ba detailed cross-sectional view of a portion of the loaded applicator indicated by circle C in FIG. 37E depicts a cross-sectional view of the applicator in a loaded configuration for deployment of an analyte monitoring device from the applicator. FIG. 37D a detailed cross-sectional view of a portion of the loaded applicator indicated by circle D in

[0068] FIG. 38 depicts a cross-sectional view of the applicator in a loaded configuration for deployment of an analyte monitoring device from the applicator.

[0069] FIG. 39A-39C depicts an upper perspective view, a side view, and a lower perspective view of the applicator, respectively. FIG. 39D depicts an exploded view of the applicator shown in FIG. 39A-39C

[0070] FIG. 40A and 40B depicts an upper perspective view and a top view of the applicator carrier, respectively.

[0071] FIG. 41A-41D depicts an upper perspective view, a top view, a lower perspective view, and a side view of the applicator trigger, respectively. FIG. 41E depicts a cross-sectional view of the trigger taken along line 26E:26E shown in FIG. 41D

[0072] are an upper perspective view, a top view, and a side view of the applicator housing, respectively. FIG. 42A-42C depicts a cross-sectional view of the housing taken along line 27D:27D shown in FIG. 42D depicts a top view of the housing shown in FIG. 42C FIG. 42E depicts a cross-sectional view of the housing taken along line 28D:28D shown in FIG. 42A 42B depicts a cross-sectional view of the applicator in a loaded configuration for deployment of an analyte monitoring device from the applicator.

[0073] FIG. 43 depicts a cross-sectional view of the applicator in a loaded configuration for deployment of an analyte monitoring device from the applicator.

[0074] FIG. 44 depicts an upper perspective view, a side view, and a lower perspective view of the applicator, respectively.

[0075] depicts an exploded view of the applicator shown in FIG. 45A-45C FIG. 45D FIG. 45A-45C

[0076] FIG. 46A-46D depicts an upper perspective view, a top view, a lower perspective view, and a side view of the applicator carrier, respectively. FIG. 46E depicts a cross-sectional view of the carrier taken along line 31E:31E shown in FIG. 46D depicts a cross-sectional view of the carrier taken along line 31E:31E shown in​​​​​

[0077] FIG. 47A-47C An upper perspective view, a lower perspective view, and a side view of an applicator trigger are respectively depicted. FIG. 47D A cross-sectional view of the trigger taken along lines 32D:32D shown in FIG. 47C

[0078] FIG. 48A-48E An upper perspective view, a lower perspective view, a bottom view, and a side view of an applicator housing are respectively depicted. FIG. 48E A cross-sectional view of the housing taken along lines 33E:33E shown in FIG. 48D

[0079] FIG. 49 A cross-sectional view of an applicator in a loaded configuration for deploying an analyte monitoring device from the applicator is depicted.

[0080] FIG. 50 A cross-sectional view of an applicator in a fired configuration for deploying an analyte monitoring device from the applicator is depicted.

[0081] FIG. 51A-51C A bottom perspective view, a side view, and a bottom view of an applicator carrier are respectively depicted.

[0082] FIG. 51D-51F A bottom perspective view, a side view, and a bottom view of an applicator carrier are respectively depicted.

[0083] FIG. 51G-51I An upper perspective view, a cross-sectional view, and a bottom view of an applicator in a loaded configuration for deploying an analyte monitoring device from the applicator are respectively depicted.

[0084] FIG. 51J-51L An upper perspective view, a cross-sectional view, and a bottom view of an applicator in a fired configuration for deploying an analyte monitoring device from the applicator are respectively depicted.

[0085] FIG. 51M and 51N An upper perspective view and a lower perspective view of an applicator carrier with an analyte monitoring device of an applicator are respectively depicted.

[0086] FIG. 52A and 52B An upper perspective view and a lower perspective view of an applicator carrier with an analyte monitoring device of an applicator are respectively depicted.

[0087] FIG. 53A An exploded view of an applicator of an applicator is depicted.

[0088] FIG. 53B-53E An upper perspective view, a top view, a lower perspective view, and a cross-sectional view of an applicator carrier are respectively depicted.

[0089] ​​FIG. 53F-53H A lower perspective view, a bottom view, and an upper perspective view of an applicator trigger are depicted.

[0090] FIG. 53I-53K A lower perspective view, a cross-sectional view, and a bottom view of an applicator actuator are depicted.

[0091] FIG. 54A and 54B A perspective view and an exploded view of an applicator conveyor are depicted. DETAILED DESCRIPTION

[0092] Non-limiting examples of aspects and variations of the present disclosure are described herein and illustrated in the accompanying drawings.

[0093] Aspects of the current subject matter relate to a microneedle enclosure for providing a protective environment in which a microneedle array of an analyte monitoring device can be safely contained. The microneedle enclosure is releasably attachable to the analyte monitoring device to protect the microneedle array prior to application of the analyte monitoring device, and the microneedle enclosure is removable from the analyte monitoring device to provide for application (e.g., insertion) of the microneedle array of the analyte monitoring device.

[0094] Other aspects of the current subject matter relate to an applicator device (also referred to as an applicator) for applying an analyte monitoring device including one or more microneedle arrays to a target area of a user. The applicator devices and variations described herein provide for safe and effective application of the analyte monitoring device to the user such that the microneedle array pierces the skin of the user to insert into the skin, such as the upper dermal region of the skin (e.g., the dermal papilla layer and the upper dermal reticular layer).

[0095] Prior to providing additional details regarding the microneedle enclosure and applicator device, the following provides an illustration of some examples of analyte monitoring devices that can be used with the microneedle enclosures and / or applicator devices described herein. The following description is exemplary and aspects of the microneedle enclosures and applicator devices consistent with the current subject matter are not limited to the exemplary analyte monitoring devices described herein.

[0096] As generally described herein, an analyte monitoring system can include an analyte monitoring device that is worn by a user and includes one or more sensors for monitoring at least one analyte of the user. For example, the sensor can include one or more electrodes configured to electrochemically detect the at least one analyte. The analyte monitoring device can communicate sensor data to an external computing device for storage, display, and / or analysis of the sensor data.

[0097] For example, as FIG. 1As shown, the analyte monitoring system 100 can include an analyte monitoring device 110 worn by a user, and the analyte monitoring device 110 can be a continuous analyte monitoring device (e.g., a continuous glucose monitoring device). The analyte monitoring device 110 can include, for example, a microneedle array including at least one electrochemical sensor for detecting and / or measuring one or more analytes in a bodily fluid of a user. In some variations, the analyte monitoring device can be applied to the user using a suitable applicator 160 (such as any of the applicators described herein). The analyte monitoring device 110 can include one or more processors for analyzing sensor data, and / or a communication module (e.g., a wireless communication module) configured to communicate sensor data to a mobile computing device 102 (e.g., a smartphone) or other suitable computing device. In some variations, the mobile computing device 102 can include one or more processors executing a mobile application to process sensor data (e.g., display data, analyze trends in data, etc.), and / or the mobile computing device 102 can provide suitable alerts or other notifications related to sensor data and / or analysis thereof. It will be appreciated that, although in some variations the mobile computing device 102 can perform sensor data analysis locally / on-site, other computing devices can alternatively or additionally analyze sensor data remotely and / or communicate information related to such analysis to the mobile computing device 102 (or other suitable user interface / user interface) for display to a user. Further, in some variations, the mobile computing device 102 can be configured to communicate sensor data and / or analysis of sensor data to one or more storage devices 106 (e.g., servers) over a network 104 for archiving data and / or other suitable information related to a user of the analyte monitoring device.

[0098] The analyte monitoring devices described herein have features that improve a number of characteristics that are beneficial for continuous analyte monitoring devices, such as continuous glucose monitoring (CGM) devices. For example, the analyte monitoring devices described herein have improved sensitivity (the amount of sensor signal produced per given concentration of target analyte), improved selectivity (rejection of endogenous and exogenous circulating compounds that can interfere with detection of the target analyte), and improved stability to help minimize changes in sensor response over time through storage and operation of the analyte monitoring device. In addition, the analyte monitoring devices described herein have a shorter warm-up time compared to traditional continuous analyte monitoring devices, enabling the sensor to provide a stable sensor signal quickly after implantation, and the analyte monitoring devices described herein have a short response time, enabling the sensor to provide a stable sensor signal quickly after a change in analyte concentration in the user. In addition, as described in further detail below, the analyte monitoring devices described herein can be applied and function at multiple different wear sites and provide painless sensor insertion for the user. Other characteristics such as biocompatibility, sterilizability, and mechanical integrity are also optimized in the analyte monitoring devices described herein.

[0099] While the analyte monitoring systems described herein can be described with reference to glucose monitoring (e.g., in users with Type 1, Type 2 diabetes), it should be understood that such systems can additionally or alternatively be configured to sense and monitor other suitable analytes. As described in further detail below, suitable target analytes for detection can include, for example, glucose, ketones, lactate, and cortisol. One target analyte can be monitored, or multiple target analytes can be monitored simultaneously (e.g., in the same analyte monitoring device). For example, monitoring of other target analytes can monitor other indications, such as stress (e.g., by detecting elevated cortisol and glucose) and ketoacidosis (e.g., by detecting elevated ketones).

[0100] As FIG. 2AAs shown, in some variations, the analyte monitoring device 110 can generally include a housing 112 and a microneedle array 140 extending outwardly from the housing. The housing 112, for example, can be a wearable housing configured to be worn on the skin of a user such that the microneedle array 140 extends at least partially into the skin of the user. For example, the housing 112 can include an adhesive such that the analyte monitoring device 110 is a skin-adhesive patch that is simple and straightforward to apply to a user. The microneedle array 140 can be configured to pierce the skin of a user and include one or more electrochemical sensors (e.g., electrodes) configured to measure one or more target analytes that are accessible after the microneedle array 140 pierces the skin of the user. In some variations, the analyte monitoring device 110 can be integrated or self-contained as a single unit, and the unit can be disposable (e.g., for use over a period of time and replaced with another analyte monitoring device 110).

[0101] The electronics system 120 can be at least partially disposed in the housing 112 and include a variety of different electronic components, such as a sensor circuit 124 configured to perform signal processing (e.g., biasing and readout of the electrochemical sensor, conversion of analog signals from the electrochemical sensor to digital signals, etc.). The electronics system 120 can also include at least one microcontroller 122 for controlling the analyte monitoring device 110, at least one communication module 126, at least one power source 130, and / or other various suitable passive circuitry 127. The microcontroller 122 may, for example, be configured to interpret digital signals output from the sensor circuit 124 (e.g., by executing programmed routines in firmware), perform various suitable algorithms or mathematical transformations (e.g., calibration, etc.), and / or route processed data to and / or from the communication module 124. In some variations, the communication module 126 can include a suitable wireless transceiver (e.g., Bluetooth transceiver, etc.) for data communication with the external computing device 102 via one or more antennas 128. For example, the communication module 126 can be configured to provide one-way and / or two-way data communication with the external computing device 102 that is paired with the analyte monitoring device 110. The power source 130 can provide power to the analyte monitoring device 110, e.g., to the electronics system. The power source 130 can include a battery or other suitable power source, and can be rechargeable and / or replaceable in some variations. The passive circuitry 127 can include various passive / parasitic circuitry (e.g., resistors, capacitors, inductors, etc.) that provide interconnections between other electronic components, etc. For example, the passive circuitry 127 can be configured to perform noise reduction, biasing, and / or other purposes. In some variations, the electronic components in the electronics system 120 can be disposed on one or more printed circuit boards (PCBs), which can be rigid, semi-rigid, or flexible, for example. Further details of the electronics system 120 will be described further below.

[0102] In some variations, the analyte monitoring device 110 can also include one or more additional sensors 150 to provide additional information that can be relevant to user monitoring. For example, the analyte monitoring device 110 can also include at least one temperature sensor (e.g., a thermistor) configured to measure skin temperature, thereby enabling temperature compensation of sensor measurements obtained by the microneedle array electrochemical sensor.

[0103] In some variations, the microneedle array 140 in the analyte monitoring device 110 can be configured to pierce the skin of a user. As FIG. 2BAs shown, when the device 110 is worn by a user, the microneedle array 140 can extend into the user's skin such that the electrodes on the distal regions of the microneedles reside in the dermis. In particular, in some variations, the microneedles can be designed to penetrate the skin and enter the upper dermal region of the skin (e.g., the dermal papilla layer and the upper dermal reticular layer) in order to enable the electrodes to access the interstitial fluid surrounding cells in these layers. For example, in some variations, the microneedles can have a height that is generally in the range of at least 350 pm to about 515 pm. In some variations, one or more microneedles can extend from the housing such that the distal end of the electrodes on the microneedles are located less than about 5 mm from the skin interface of the housing, less than about 4 mm from the housing, less than about 3 mm from the housing, less than about 2 mm from the housing, or less than about 1 mm from the housing.

[0104] In contrast to traditional continuous analyte monitoring devices (such as CGM devices) that include sensors implanted in the subcutaneous tissue or fat layer of the skin generally at about 8 mm to about 10 mm below the surface of the skin, the analyte monitoring device 110 has a shallow microneedle insertion depth of about 0.25 mm (such that the electrodes are implanted in the upper dermal region of the skin). These benefits include access to the dermal interstitial fluid that contains one or more target analytes for detection, which is advantageous at least because it has been found that measurements of at least some types of analytes in the dermal interstitial fluid are closely correlated with measurements in blood. For example, it has been found that glucose measurements using electrochemical sensors that contact the dermal interstitial fluid are advantageously highly linearly correlated with blood glucose measurements. Thus, glucose measurements based on the dermal interstitial fluid are highly representative of blood glucose measurements.

[0105] Furthermore, because of the shallow microneedle insertion depth of the analyte monitoring device 110, the time delay for analyte detection is reduced compared to traditional continuous analyte monitoring devices. This shallow insertion depth brings the sensor surface in close proximity (e.g., within a few hundred microns or less) to the dense and well-perfused capillary bed of the dermal reticular layer, resulting in negligible diffusion lag from the capillaries to the sensor surface. The diffusion time is proportional to the diffusion distance according to t = x 2where t is the diffusion time, x is the diffusion distance, and D is the mass diffusivity of the analyte of interest. Thus, positioning the analyte sensing element twice as far from the source of the analyte in the capillary vessel will result in a four-fold diffusion delay time. Thus, a conventional analyte sensor residing in the hypodermically very poorly vascularized adipose tissue results in a significantly greater diffusion distance from the vasculature in the dermis, resulting in a considerable diffusion delay (e.g., typically 5-20 minutes). In contrast, the shallower microneedle insertion depth of the analyte monitoring device 110 benefits from a low diffusion delay from the capillary to the sensor, thereby reducing the time delay in analyte detection and providing more accurate results in real-time or near real-time. For example, in some embodiments, the diffusion delay can be less than 10 minutes, less than 5 minutes, or less than 3 minutes.

[0106] Furthermore, when the microneedle array is positioned in the upper dermis region, the lower dermis beneath the microneedle array includes very high levels of vascularization and perfusion to support the metabolism of the dermis, enabling temperature regulation (through vasoconstriction and / or vasodilation) and providing a barrier function to help stabilize the sensing environment around the microneedles. Another advantage of the shallower insertion depth is that the upper dermis layer lacks nociceptors, thus reducing the sensation of pain when the microneedle array pierces the user’s skin and providing a more comfortable, minimally-invasive user experience.

[0107] Accordingly, the analyte monitoring devices and methods described herein enable improved continuous monitoring of one or more target analytes of a user. For example, as described above, the analyte monitoring devices can be applied simply and directly, which improves ease of use and user compliance. Furthermore, analyte measurements of the interstitial fluid of the dermis can provide highly accurate analyte detection. Moreover, the insertion of the microneedle array and its sensors is less invasive and less painful to the user compared to traditional continuous analyte monitoring devices. Other advantages of other aspects of the analyte monitoring devices and methods will be further described below.

[0108] FIG. 3A-FIG. 3D Aspects of the analyte monitoring device 110 are depicted. FIG. 3A-3D An upper perspective view, a side view, a bottom view, and an exploded view of the analyte monitoring device 110 are respectively depicted.

[0109] The analyte monitoring device 110 can include a housing that can at least partially enclose or encapsulate other components (e.g., electronic components) of the analyte monitoring device 110, for example, for protection of the components. For example, the housing can be configured to help prevent dust and moisture from entering the analyte monitoring device 110. In some variations, an adhesive layer can attach the housing to a surface (e.g., skin) of a user while allowing the microneedle array 140 to extend outward from the housing and into the skin of the user. Further, in some variations, the housing can generally include rounded edges or corners and / or a low profile in order to reduce interference with clothing or the like worn by the user.

[0110] For example, as shown in FIG. 3A, an example variation of the analyte monitoring device 110 can include a housing cover 320 and a substrate 330 configured to at least partially enclose internal components of the analyte monitoring device 110. For example, the housing cover 320 and the substrate 330 can provide an enclosure for a sensor assembly 350 including the microneedle array 140 and electronic components. Once assembled, the microneedle array 140 extends outward from a portion of the substrate 330 in a skin-facing direction (e.g., a lower side) of the analyte monitoring device 110. FIG. 3A-3D For example, the housing cover 320 and the substrate 330 can include one or more rigid or semi-rigid shell components that can be coupled together by suitable fasteners (e.g., mechanical fasteners), mechanical interlocks or mating features, and / or engineering fits. The housing cover 320 and the substrate 330 can include rounded edges and corners and / or other damage- resistant features. When coupled together, the housing cover 320 and the substrate 330 can form an internal volume that houses the internal components (e.g., the sensor assembly 350). For example, the internal components disposed in the internal volume can be arranged as a compact, low-profile stack of the sensor assembly 350.

[0111] The analyte monitoring device 110 can include one or more adhesive layers to attach the analyte monitoring device 110 (e.g., the coupled together housing cover 320 and substrate 330) to a surface (e.g., skin) of a user. As shown in FIG. 3A, for example, the analyte monitoring device 110 can include an adhesive layer 340 disposed between the substrate 330 and the skin of the user. The adhesive layer 340 can be configured to attach the analyte monitoring device 110 to the skin of the user while allowing the microneedle array 140 to extend outward from the substrate 330 and into the skin of the user.

[0112] FIG. 3D ​As shown, the one or more adhesive layers can include an inner adhesive layer 342 and an outer adhesive layer 344. The inner adhesive layer 342 can be adhered to the substrate 330, and the outer adhesive layer 344 can be adhered to the inner adhesive layer 342 and, on its outward-facing side, provide an adhesive for adhering (e.g., temporarily) to a user’s skin. Together, the inner adhesive layer 342 and the outer adhesive layer 344 act as a double-sided adhesive for adhering the analyte monitoring device 110 to a user’s skin. The outer adhesive layer 344 can be protected by a release liner that the user removes to expose the adhesive prior to skin application. In some variations, a single adhesive layer is provided. In some variations, the outer adhesive layer 344, the inner adhesive layer 342, and / or the single adhesive layer can have a perimeter that extends farther than the perimeter or periphery of the housing cover 320 and the substrate 330. This can increase the surface area for attachment and increase the stability of holding or adhering to a user’s skin. The inner adhesive layer 342, the outer adhesive layer 344, and / or the single adhesive layer each have an opening that allows the outwardly extending microneedle array 140 to pass through, as further described below. The openings of the inner adhesive layer 342 and the outer adhesive layer 344 can be generally aligned with each other, but in some variations, can differ in size such that one opening is smaller than the other. In some variations, the openings are substantially the same size.

[0113] The substrate 330 has a first surface (e.g., outwardly exposed surface) opposite the second surface, and the substrate serves as a support and / or connection structure for the sensor assembly 350 and as a protective cover. The substrate 330 is sized and shaped to be attachable to the housing cover 320. The shape of the substrate 330 can be determined to fit securely within the housing cover 320 such that the outer edges of the substrate 330 are aligned with the corresponding edges of the opening of the housing cover 320. This alignment can be such that there is no gap between the outer edges of the substrate 330 and the corresponding edges of the opening of the housing cover 320.

[0114] The connection member 332 can be formed in or near a central region of the first surface of the substrate 330. The connection member 332 is a protrusion (e.g., a protruding hub) having a sidewall extending from the first surface of the substrate 330 and a first surface substantially parallel to the first surface of the substrate 330. The sidewall extends from an edge of the first surface of the connection member 332 to the first surface of the substrate 330. The remainder of the first surface of the substrate 330 around the connection member 332 can be flat or substantially flat. One or more connector features 336 extend outwardly from the sidewall of the connection member 332 to releasably engage with a corresponding connector of a microneedle enclosure, as further described below. The first surface and the sidewall of the connection member 332 partially define a cavity. The cavity can be further defined by a portion of the substrate 330 adjacent to the connection member 332 (e.g., beneath the connection member 332). The cavity has an opening on the second surface of the substrate 330 and is accessible on the second surface of the substrate 330. A hole 334 is formed through the first surface of the connection member 332. The hole 334 can be sized and shaped such that the microneedle array 140 is securely mounted within the hole 334 and extends through the hole 334. For example, the sidewall of the microneedle array 140 can be aligned with a corresponding sidewall of the hole 334. In some variations, the hole 334 can be sized and shaped to correspond to a region surrounding the microneedle array 140. The openings in the inner adhesive layer 342 and the outer adhesive layer 344 (or a single adhesive layer) are sized such that the connection member 332 extends through the openings without interfering with the adhesive layers. For example, the diameter of the openings in the inner adhesive layer 342 and the outer adhesive layer 344 is greater than the diameter of the openings in the connection member 332. In some variations, the openings in the inner adhesive layer 342 and / or the outer adhesive layer 344 (or the openings in a single adhesive layer) have a gap adjacent to the sidewall of the connection member 332 for accommodating the one or more connector features 336. In some variations, one or more slits or recesses can be formed in the inner adhesive layer 342, the outer adhesive layer 344, and / or a single adhesive layer that extend from the openings to facilitate placement of the respective adhesive layer.

[0115] Although FIG. 3A-3D The housing cover 320 and the substrate 330 are shown as substantially circular with the housing cover 320 being dome-shaped, in other variations, the housing cover 320 and the substrate 330 can be any suitable shape. For example, in other variations, the housing cover 320 and the substrate 330 can be generally prismatic and have an elliptical, triangular, rectangular, pentagonal, hexagonal, or other suitable shape. The outer adhesive layer 344 (or a single adhesive layer) can extend outwardly from the housing cover 320 and the substrate 330 to extend beyond the perimeter / circumference of the housing cover 320. The outer adhesive layer 344 (or a single adhesive layer) can be circular, as shown in FIG. 3, or can be shaped to correspond to the shape of the housing cover 320 and the substrate 330.FIG. 3A-3D The sensor assembly 350 can have any suitable shape, such as a circular shape, as shown, or can have an elliptical, triangular, rectangular, pentagonal, hexagonal, or other suitable shape, and need not be the same shape as the housing cover 320 and / or the base plate 330.

[0116] FIG. 4A-4E Aspects of the sensor assembly 350 of the analyte monitoring device 110 are depicted in a perspective exploded view, a side exploded view, a lower perspective view, a side view, and an upper perspective view, respectively.

[0117] The sensor assembly 350 includes a microneedle array component and an electronics component to implement analyte detection and processing aspects of the microneedle array-based continuous analyte monitoring device 110 for detecting and measuring analytes. In some variations, the sensor assembly 350 is a compact, low-profile stack that is at least partially contained within an interior volume defined by the housing cover 320 and the base plate 330.

[0118] In some variations, the sensor assembly 350 includes a microneedle array assembly 360 and an electronics assembly 370 that are interconnected to implement microneedle array analyte detection and processing aspects described further herein. In some variations, the electronics assembly 370 includes a primary printed circuit board (PCB) 450 on which electronics components are connected, and the microneedle array assembly 360 includes a secondary printed circuit board (PCB) 420 on which the microneedle array 140 is connected.

[0119] In some variations, in addition to the secondary PCB 420 and the microneedle array 140, the microneedle array assembly 360 includes an epoxy skirt 410 and a secondary PCB connector / secondary PCB connector 430. The microneedle array 140 is coupled to a top side (e.g., an outward-facing side) of the secondary PCB 420 such that individual microneedles of the microneedle array 140 are exposed, as described with reference to FIGS. 4A-4B, for example. The secondary PCB connector 430 is coupled to a back side of the secondary PCB 420 opposite the top side. The secondary PCB connector 430 can be an electromechanical connector and can be communicatively coupled to the primary PCB 450 through a primary PCB connector 470 on a top side (e.g., an outward-facing side) of the primary PCB 450 to allow signal communication between the secondary PCB 420 and the primary PCB 450. For example, signals from the microneedle array 140 can be communicated through the secondary PCB 420, the secondary PCB connector 430, and the primary PCB connector 470 to the primary PCB 450. FIG. 3A-FIG. 3D

[0120] ​The auxiliary PCB 420 can partially determine the distance that the microneedle array 140 protrudes from the housing substrate 330. Accordingly, the height of the auxiliary PCB 420 can be selected to help ensure that the microneedle array 140 is properly inserted into the skin of a user. During microneedle insertion, the first surface (e.g., the outward-facing surface) of the connecting member 332 of the substrate 330 can act as a stop for microneedle insertion. If the auxiliary PCB 420 has a reduced height and its top surface is flush or nearly flush with the first surface of the connecting member 332, the connecting member 332 can prevent the microneedle array 140 from being fully inserted into the skin.

[0121] In some variations, other components (e.g., electronic components, such as sensors or other components) can also be connected to the auxiliary PCB 420. For example, the size and shape of the auxiliary PCB 420 can be determined to accommodate electronic components on the top side or the back side of the auxiliary PCB 420.

[0122] In some variations, an epoxy skirt 410 can be deposited along the edges (e.g., the outer perimeter / circumference) of the microneedle array 140 to secure the microneedle array 140 within the hole 334 formed in the connecting member 332 of the substrate 330 and / or to mitigate / relieve sharp edges along the edges of the microneedle array 140 as shown. FIG. 3C and FIG. 3D The epoxy skirt 410 can occupy portions of the hole 334 not filled by the microneedle array 140 and / or portions of the cavity defined in the substrate 330 not filled by the auxiliary PCB 420. The epoxy skirt 410 can also provide a transition from the edges of the microneedle array 140 to the edges of the auxiliary PCB 420. In some variations, the epoxy skirt 410 can be replaced or supplemented by a gasket (e.g., a rubber gasket) or the like.

[0123] The electronics assembly 370 with the main PCB 450 includes a battery 460 coupled to the main PCB 450 opposite the top side on which the main PCB connector 470 is coupled.

[0124] FIG. 4F-4H Aspects of an alternative variation of the sensor assembly 350 of the analyte monitoring device 110 are depicted. A perspective exploded view, a side exploded view, and a side view of the sensor assembly 350 are respectively provided in FIG. 4F-4H

[0125] ​As shown, in the sensor assembly 350, an additional PCB component is incorporated, namely the middle PCB 425. In some variations, the middle PCB 425 is part of the microneedle array assembly 360 and is positioned between and connected to the auxiliary PCB 420 and the microneedle array 140. The middle PCB 425 can be added to increase the height of the microneedle array assembly 360 such that the microneedle array 140 extends a greater distance from the base plate 330, which can aid in the insertion of the microneedle array 140 into the skin of a user. The microneedle array 140 is coupled to the top side (e.g., the outward-facing side) of the middle PCB 425 such that the individual microneedles of the microneedle array 140 are exposed, as described with reference to FIG. 3A, for example. The auxiliary PCB 420 is coupled to the back side of the middle PCB 425 opposite the top side, and the auxiliary PCB connector 430 is coupled to the back side of the auxiliary PCB 420 opposite the top side. The epoxy skirt 410 (which can be replaced or supplemented by a gasket or the like) provides a transition from the edge of the microneedle array 140 to the edge of the middle PCB 425. FIG. 3A-FIG. 3D

[0126] The middle PCB 425 and the auxiliary PCB 420, in part, determine the distance that the microneedle array 140 extends through the hole 334 of the base plate 330. The incorporation of the middle PCB 425 provides additional height to help ensure that the microneedle array 140 is properly inserted into the skin of a user. In some variations, the top side (e.g., the outward-facing side) of the middle PCB 425 extends through and out of the hole 334 such that the first surface (e.g., the top exposed surface) of the connecting member 332 surrounding the hole 334 does not prevent the microneedle array from fully inserting into the skin. In some variations, the top side (e.g., the outward-facing side) of the middle PCB 425 does not extend out of the hole 334, but the increased height (due to the incorporation of the middle PCB 425) ensures that the microneedle array 140 protrudes a sufficient distance from the base plate 330 of the housing.

[0127] In some variations, a microneedle enclosure can be provided for releasably attaching to the analyte monitoring device 110. The microneedle enclosure can provide a protective environment or enclosure in which the microneedle array 140 can be safely housed, thereby ensuring the integrity of the microneedle array 140 during certain stages of manufacture and shipping of the analyte monitoring device 110 prior to application of the analyte monitoring device 110. The microneedle enclosure can be released or removed from the analyte monitoring device 110 to allow the microneedle array 140 to be exposed and ready for insertion into the skin of a user, as described further herein.

[0128] ​In some variations, the microneedle enclosure provides an environment in which the microneedle array 140 can be sterilized by providing an enclosed and sealed environment in which the microneedle array 140 can be housed. For example, the microneedle enclosure with the microneedle array 140 can be subjected to a sterilization process during which sterilization penetrates the microneedle enclosure such that the microneedle array 140 is also sterilized. Because the microneedle array 140 is contained in an enclosed environment, the microneedle array 140 remains sterile until removed from the enclosed environment.

[0129] FIG. 5A-5D Aspects of the microneedle enclosure 500 are depicted in the form of an exploded view, a first side view and side cross-sectional view, a second side view and side cross-sectional view, and a bottom perspective view, respectively. The microneedle enclosure 500 includes a casing 510, a clamp 520, and a biasing element 530 (e.g., a spring). In some variations, the microneedle enclosure 500 can also include a force concentrator 540.

[0130] The casing 510 is a housing, enclosure, or the like, having a sidewall that surrounds and / or encloses the microneedle array 140 and provides an enclosed, sealed environment for the microneedle array 140. The casing 510 has an opening at a distal end through which the microneedle array 140 is positioned such that the interior of the sidewall of the casing 510 encloses the microneedle array 140. A bumper 512 can be positioned at the distal end of the casing 510 such that the bumper 512 encloses the opening of the casing 510 at the distal end. The bumper 512 can be a ring-shaped, elastic bumper or the like that provides a tight seal that is maintained around the distal end of the casing 510. The bumper 512 is sized and shaped to correspond to the size and shape of the opening of the casing 510 at the distal end. The inner perimeter of the casing 510 (e.g., the perimeter of the opening) can be aligned or substantially aligned with the footprint of the microneedle array 140. For example, the size and shape of the inner perimeter of the casing 510 can be sized and shaped to align with the outer perimeter of the microneedle array 140 such that the microneedle array 140 is completely contained within the casing 510 with the microneedles extending into the casing 510.

[0131] The clamp 520 includes a cavity defined by the clamp 520 sidewall. The cavity can include a first cavity 522 and a second cavity 524, each of which is defined by the sidewall of the clamp 520. The second cavity 524 is adjacent to the first cavity 522 in a region proximal to the first cavity 522, and the second cavity 524 is a proximal extension of the first cavity 522 such that the first cavity 522 and the second cavity 524 are fluidly connected. The first cavity 522 is sized and shaped to accommodate the sheath 510. An opening at the distal end of the clamp 520 provides an access point into the first cavity 522, allowing the sheath 510 to be assembled in the first cavity 522 through the opening. The second cavity 524 is sized and shaped to accommodate the biasing element 530. When the biasing element 530 and the sheath 510 are positioned within the clamp 520 (e.g., through the opening at the distal end of the clamp 520), the biasing element 530 is securely but moveably contained within the second cavity 524, and the outer sidewall of the sheath 510 is aligned with and can abut against the sidewall of the first cavity 522. In some variations, one or more portions of the outer sidewall of the sheath 510 contact corresponding one or more portions of the first cavity 522, such that the sheath 510 is wedged or a tight fit within the first cavity 522, such that the sheath 510 is integrated / as one piece with the clamp 520. The biasing element 530 can generally correspond in size and shape to the second cavity 524, and extend in a distal direction from an upper region of the second cavity 524 to or near the top surface of the sheath 510. The biasing element 530 can be slightly smaller in diameter than the inner diameter of the second cavity 524 to limit horizontal movement of the biasing element 530 within the clamp 520. The biasing element 530 can be a helical metal spring, a plastic leaf spring, a helical plastic spring, or any form of spring capable of providing compliance between the clamp 520 and the sheath 510, as further described herein.

[0132] In some variations, a force concentrator 540 can be positioned within the biasing element 530, with a distal region extending out of the biasing element 530 and in contact with the top surface of the sheath 510. For example, the force concentrator 540 can include a shaft and a head. The shaft can be assembled within the biasing element 530, and the head can extend distally through the biasing element 530 to contact the top surface of the sheath 510. The biasing element 530 and optional force concentrator 540 are combined to provide a sealed downward force on the sheath 510 and the bumper 512, maintaining a sealed enclosure of the microneedle array 140 when the clamp 520 is engaged with the analyte monitoring device 110, as further described herein. The force concentrator 540 provides a downward force to the engaged top surface of the sheath 510 to eliminate the transfer of torque to the bumper 512 during manufacturing and / or assembly. For example, the force concentrator 540 eliminates rotation of the bumper 512 during manufacturing and / or assembly.

[0133] The clip 520 also includes an external engagement feature 526 and a locking tab 528. The external engagement feature 526 is configured to engage with a portion of the applicator device, as further described herein. The locking tab 528 is formed on the respective interior of the sidewall of the clip 520 at the distal end of the clip 520, as FIG. 5D The locking tab 528 can be a protrusion extending orthogonally outward from the interior of the sidewall of the clip 520 and can be configured to releasably engage with the substrate 330, as further described below.

[0134] FIG. 5E-5G Aspects of the microneedle enclosure 500, the substrate 330 of the analyte monitoring device 110, and the releasable coupling therebetween are depicted. The microneedle enclosure 500 is configured to releasably attach or couple to the substrate 330 by engagement with the connecting member 332. The microneedle array assembly 360 portion of the sensor assembly 350 is assembled within a cavity formed by the substrate 330 and the connecting member 332, with the microneedle array 140 extending through the aperture 334 of the substrate 330. As FIG. 5G As shown in the side cross-sectional view of FIG. 6, when the microneedle enclosure 500 is attached to the substrate 330, the microneedle array 140 is contained within the casing 510, with the bumper 512 providing a seal between the casing 510 and the substrate 330. In some variations, the bottom edge of the sidewall of the microneedle enclosure 500 interfaces with and / or abuts the first surface of the substrate 330 around and / or adjacent to the outer edge of the connecting member 322. In some variations, the bottom edge of the sidewall of the casing 510 and the bottom edge of the bumper 512 interface with and / or abut the first surface of the connecting member 332 around and / or adjacent to the outer edge of the aperture 334. In some variations, the outer diameter of the casing 510 is equal to or slightly smaller than the diameter of the first surface of the connecting member 322. The diameter of the opening of the casing 510 is of sufficient size to accommodate the aperture 334 without interfering with the microneedle array 140. The sidewall of the opening of the casing 510 can interface with and / or abut the edge around the microneedle array 140 such that the sidewall of the opening of the casing 510 surrounds the edge of the microneedle array 140.

[0135] To form a releasable attachment or connection between the substrate 330 and the microneedle housing 500, a connector feature 336 of the connecting member 332 releasably engages with a locking tab 528 of the microneedle housing 500. In some variations, the connector feature 336 may be a bayonet connector that engages and disengages with the locking tab 528 by a torsional or rotational movement. For example, the connector feature 336 may include an extension blade orthogonally projecting from an upper region of the connecting member 332. Each extension blade may terminate at one end in a stop feature (e.g., a vertical wall or a vertically extending barrier) extending from the upper edge of the respective extension blade to a first surface of the substrate 330. These connector features 336 may be circumferentially positioned around the outer edge of the connecting member 332, and each connector feature 336 may correspond to a corresponding locking tab 528 of the microneedle housing 500. The locking tab 528 engages with the connector feature 336 by sliding beneath the extension blade and engaging the stop feature as the microneedle housing 500 rotates relative to the substrate 330. In some variations, the microneedle housing 500 is positioned above the connecting member 332 and rotated until further rotation is prevented by the locking tab 528 of the stop feature of the engaging connector feature 336. Rotation in the opposite direction disengages the locking tab 528 from the stop feature, allowing the microneedle housing 500 to disengage from the connecting member 332, at which point the microneedle housing 500 can be lifted or pulled away from the substrate 330. Other types of connecting members forming a releasable connection can be used. In some variations, three connector features 336 and three locking tabs 528 can be combined. In other variations, one, two, four, or more pairs of connector features 336 and locking tabs 528 can be combined.

[0136] like FIG. 5G As shown, when the microneedle housing 500 is attached to the substrate 330 including the microneedle array assembly 360, the sheath 510 is aligned around the microneedle array 140 on the first surface of the connecting member 322. When the microneedle housing 500 is positioned above the connecting member 322 and twisted to engage the one or more connector features 336, the biasing element 530 is biased to maintain a stable connection between the sheath 510 and the clamp 520. The force concentrator 540 provides a downward force to the sheath 510 and the buffer 512 to eliminate torque transmission to the buffer 512, preventing the buffer 512 from rotating during twisting operations. This maintains the sterile barrier provided by the sheath 510 and the buffer 512. The inner periphery of the opening of the sheath 510 and the edge of the microneedle array 140 are tightly sealed, so that the clamp 520, sheath 510, buffer 512, biasing element 530, and force concentrator 540 provide a tight enclosure / encapsulation around the microneedle array 140.

[0137] The microneedle array assembly 360, including the microneedle array 140, can be sterilized with the microneedle array assembly 360 assembled within the substrate 330 and the microneedle enclosure 500 coupled to the microneedle array assembly 360. For example, a radiation sterilization method can be applied. In some variations, the components are sterilized to a sterility assurance level (SAL) of 10 -6 -6. Notably, the sterilization is performed with the microneedle array assembly 360 not connected to the electronics assembly 370. After the sterilization process, the substrate 330 is attached to the housing cover 320 and the electronics assembly 370 is positioned in the housing cover 320. The attachment includes establishing a connection between the microneedle array assembly 360 and the electronics assembly 370 through the respective PCB connectors 430 and 470. Since the microneedle array 140 is contained within the sealed microneedle enclosure 500, the sterile environment containing the microneedle array 140 is not compromised. The assembled analyte monitoring device 110, along with the attached microneedle enclosure 500, can be contained in an applicator device, as further described herein.

[0138] The configuration of the microneedle enclosure 500 described herein allows for mass sterilization. For example, multiple assemblies including the microneedle array assembly 360, the substrate 330, and the microneedle enclosure 500 can be assembled as described herein. Then, the multiple assemblies can be exposed to radiation to sterilize each microneedle array 140. In some variations, one or more trays, containers, or the like containing the multiple assemblies can be placed in an enclosed environment or sterilization chamber where radiation can be applied. This results in the multiple assemblies being sterilized simultaneously, enabling mass manufacturing of analyte monitoring devices.

[0139] In some variations, the electronics system of the analyte monitoring device can include an analog front end. The analog front end can include sensor circuitry (e.g., as described in connection with FIG. 2) and / or other circuitry to process signals from the sensor circuitry. In some variations, the analog front end can include a preamplifier, a filter, a bias tee, and / or other circuitry to process signals from the sensor circuitry. FIG. 2AThe illustrated sensor circuit 124) converts the analog current measurements to digital values that can be processed by the microcontroller. For example, the analog front end can include a programmable analog front end suitable for electrochemical sensors. For example, the analog front end can include the MAX30131, MAX30132, or MAX30134 components (which have 1, 2, and 4 channels, respectively) available from Maxim Integrated (San Jose, CA), which are ultra-low power programmable analog front ends for electrochemical sensors. The analog front end can also include the AD5940 or AD5941 devices available from Analog Devices (Norwood, MA), which are high-precision impedance and electrochemical front ends. Similarly, the analog front end can also include the LMP91000 available from Texas Instruments (Dallas, TX), which is a configurable analog front end regulator for low-power chemical sensing applications. The analog front end can provide biasing and complete measurement paths, including an analog-to-digital converter (ADC). Ultra-low power can allow for continuous biasing of the sensor to maintain accuracy and fast response when measurements are needed for long periods of time (e.g., 7 days) using a body-worn battery-powered device.

[0140] In some variations, the analog front end device can be compatible with two- and three- terminal electrochemical sensors, for example, to enable DC current measurement, AC current measurement, and electrochemical impedance spectroscopy (EIS) measurement capabilities. In addition, the analog front end can include an internal temperature sensor and programmable reference voltage source, support for external temperature monitoring and external reference voltage source, and integrated voltage monitoring of bias and supply voltages to ensure safety and compliance.

[0141] In some variations, the analog front end can include a multi-channel regulator to multiplex sensor inputs and process multiple signal channels. For example, the analog front end can include a multi-channel regulator, such as the multi-channel regulator described in U.S. Patent No. 9,933,387, which is incorporated herein by reference in its entirety.

[0142] In some variations, the analog front end and peripheral electronics can be integrated into an application-specific integrated circuit (ASIC), for example, which can help reduce cost. In some variations, the integration scheme can include the following microcontroller.

[0143] In some variations, the electronics system of the analyte monitoring device can include at least one microcontroller (e.g., as described above in connection with the microcontroller 126), which can be configured to perform the following functions. FIG. 2AThe microcontroller can include, for example, a processor with integrated flash memory. In some variations, the microcontroller in the analyte monitoring device can be configured to perform analysis to correlate the sensor signal to an analyte measurement (e.g., a glucose measurement). For example, the microcontroller can execute programmed routines in firmware to interpret the digital signal (e.g., from the analog front end), perform any relevant algorithms and / or other analysis, and route the processed data to and / or from the communication module. Keeping the analysis on the analyte monitoring device can, for example, enable the analyte monitoring device to broadcast / transmit analyte measurement results to multiple devices in parallel (e.g., a mobile computing device such as a smart phone or smart watch, a therapy delivery system such as an insulin pen or pump, etc.) while ensuring that each connected device has the same information.

[0144] In some variations, the microcontroller can be configured to enable and / or disable the analyte monitoring device under one or more detection conditions. For example, the device can be configured to power on the analyte monitoring device after the microneedle array is inserted into the skin. This can, for example, implement a power saving feature in which the battery is disconnected until the microneedle array is placed in the skin, at which point the device can begin transmitting sensor data. Such a feature can, for example, help improve the shelf life of the analyte monitoring device and / or simplify the analyte monitoring device-external device pairing process for the user.

[0145] As FIG. 6A shown in the schematic diagram, in some variations, a microneedle array 600 for sensing one or more analytes can include one or more microneedles 610 protruding from a base surface 602. For example, the base surface 602 can be generally flat, and the one or more microneedles 610 can protrude perpendicularly from the flat surface. Generally, as shown in FIG. 6B the microneedle 610 can include a body portion 612 (e.g., a shaft) and a tapered distal portion 614 configured to pierce the skin of a user. In some variations, the tapered distal portion 614 can terminate at an insulated distal tip 616. The microneedle 610 can also include an electrode 620 on the surface of the tapered distal portion. In some variations, electrode-based measurements can be made at the interface of interstitial fluid located in the body and the electrode (e.g., across the outer surface of the microneedle). In some variations, the microneedle 610 can have a solid core (e.g., a solid body portion), but in some variations, the microneedle 610 can include one or more lumens, which can be used, for example, for drug delivery or sampling of dermal interstitial fluid. Other microneedle variations, such as those described below, can similarly include a solid core or one or more lumens.

[0146] The microneedle array 600 can be formed at least in part from a semiconductor (e.g., silicon) substrate and include various layers of material applied and shaped using various suitable microelectromechanical systems (MEMS) fabrication techniques (e.g., deposition and etching techniques), as further described below. Similar to a typical integrated circuit, the microneedle array can be reflow soldered to a circuit board. Further, in some variations, the microneedle array 600 can include a three-electrode setup including a working (sensing) electrode having an electrochemical sensing coating (including a biological recognition element, such as an enzyme) capable of detecting a target analyte, a reference electrode, and a counter electrode. In other words, the microneedle array 600 can include at least one microneedle 610 containing a working electrode, at least one microneedle 610 containing a reference electrode, and at least one microneedle 610 containing a counter electrode. Further details of these types of electrodes are described in further detail below.

[0147] In some variations, the microneedle array 600 can include multiple microneedles that are insulated such that the electrodes on each of the multiple microneedles are individually addressable / accessible and electrically isolated from all other electrodes on the microneedle array. The final individual addressability capability of the microneedle array 600 can provide better control over the function of each electrode, as each electrode can be individually probed. For example, the microneedle array 500 can be used to provide multiple independent measurements of a given target analyte, which improves the sensing reliability and accuracy of the device. Further, in some variations, the electrodes of multiple microneedles can be electrically connected to produce an enhanced signal level. As another example, the same microneedle array 600 can additionally or alternatively be interrogated to simultaneously measure multiple analytes, thereby providing a more comprehensive assessment of a physiological state. For example, as shown in the schematic diagram of FIG. 6B, the microneedle array can include a first portion of microneedles for detecting a first analyte A, a second portion of microneedles for detecting a second analyte B, and a third portion of microneedles for detecting a third analyte C. It will be appreciated that the microneedle array can be configured to detect any suitable number of analytes (e.g., 1, 2, 3, 4, 5, or more, etc.). Suitable target analytes for detection can include, for example, glucose, ketones, lactate, and cortisol. For example, in some variations, ketones can be detected in a manner similar to that described in U.S. Patent Application No. 16 / 701,784, which is incorporated by reference herein in its entirety. Thus, the individual electrical addressability capability of the microneedle array 600 provides greater control and flexibility in the sensing function of the analyte monitoring device. FIG. 7

[0148] ​In some variations of microneedles (e.g., microneedles having working electrodes), the electrode 620 can be located proximal to the insulated distal tip 616 of the microneedle. In other words, in some variations, the electrode 620 does not cover the tip of the microneedle. Rather, the electrode 620 can be offset from the tip or point of the microneedle. Electrodes 620 that are proximal to the insulated distal tip 616 of the microneedle or offset from the insulated distal tip 616 of the microneedle advantageously provide more accurate sensor measurements. For example, such an arrangement prevents the concentration of an electric field at the microneedle tip 616 during the manufacturing process, thereby avoiding uneven electrodeposition of the sensed chemical on the surface of the electrode 620, which can lead to false sensing.

[0149] As another example, placing the electrode 620 at a location offset from the tip of the microneedle can further improve sensing accuracy by reducing undesirable signal artifacts and / or false sensor readings caused by stress upon insertion of the microneedle. The distal tip of the microneedle is the first region to penetrate the skin and is therefore subjected to the greatest stress caused by mechanical shearing phenomena that accompany skin laceration or cutting. If the electrode 620 is placed on the tip or point of the microneedle, such mechanical stress can delaminate the electrochemical sensing coating on the surface of the electrode when the microneedle is inserted, and / or cause a small but interfering amount of tissue to be delivered onto the active sensing portion of the electrode. Thus, placing the electrode 620 sufficiently offset from the tip of the microneedle can improve sensing accuracy. For example, in some variations, the distal edge of the electrode 620 can be located at least about 10 pm (e.g., about 20 pm to about 30 pm) from the distal tip or point of the microneedle, as measured along the longitudinal axis of the microneedle.

[0150] The body portion 612 of the microneedle 610 can also include a conductive path extending between the electrode 620 and a backside electrode or with other electrical contacts (e.g., disposed on a backside of the microneedle array substrate). The backside electrode can be soldered to a circuit board such that electrical communication with the electrode 620 can be achieved via the conductive path. For example, during use, in vivo sensing current (within the dermis) measured at the working electrode is interrogated by the backside electrical contacts, and the conductive path facilitates electrical connection between the backside electrical contacts and the working electrode. In some variations, this conductive path can be facilitated by metal passing through the interior of the microneedle body portion (e.g., shaft) between the proximal and distal ends of the microneedle. Alternatively, in some variations, the conductive path can be provided by the entire body portion being formed of a conductive material (e.g., doped silicon). In some of these variations, the complete substrate on which the microneedle array 600 is built can be conductive, and each microneedle 610 in the microneedle array 600 can be electrically isolated from adjacent microneedles 610, as described below. For example, in some variations, each microneedle 610 in the microneedle array 600 can be electrically isolated from adjacent microneedles 610, with an insulating barrier comprising an electrically insulating material (e.g., a dielectric material, such as silicon dioxide) surrounding the conductive path extending between the electrode 620 and the backside electrical contacts. For example, the body portion 612 can include an insulating material forming a sheath around the conductive path, thereby preventing electrical communication between the conductive path and the substrate. Other example variations of structures that can enable electrical isolation between microneedles will be described in greater detail below.

[0151] This electrical isolation between microneedles in a microneedle array allows for individually addressable sensors. This individual addressability capability advantageously enables independent and parallel measurements between sensors, as well as dynamic reconfiguration of sensor assignments (e.g., for different analytes). In some variations, the electrodes in a microneedle array can be configured to provide redundant analyte measurements, which is an advantage over conventional analyte monitoring devices. For example, redundancy can improve performance by increasing reliability of the device (by reducing the likelihood of complete failure) and / or increasing accuracy (e.g., averaging multiple analyte measurements of the same analyte, which reduces the impact of extremely high or low sensor signals on determination of analyte levels).

[0152] In some variations, as described in further detail below with respect to various different variations of microneedles, the microneedle array can be formed at least in part using suitable semiconductor and / or MEMS fabrication techniques and / or mechanical cutting or dicing. Such processes, for example, facilitate large-scale, low-cost manufacturing of microneedle arrays. For example, in some variations, the microneedle array can be formed at least in part using the techniques described in U.S. Patent Application No. 15 / 913,709, which is incorporated by reference herein in its entirety.

[0153] A number of example variations of microneedle structures are described herein that incorporate one or more of the microneedle features of the microneedle arrays in the analyte monitoring devices described above.

[0154] In some variations, the microneedle can have a generally cylindrical body portion and a tapered distal portion with an electrode. For example, FIG. 8A-8C An example variation of a microneedle 800 extending from a substrate 802 is shown. FIG. 8A is a schematic side cross-sectional view of the microneedle 800, while FIG. 8B is a perspective view of the microneedle 800, FIG. 8C is a detailed perspective view of a distal portion of the microneedle 800. As FIG. 8B and 8C shown, the microneedle 800 can include a cylindrical body portion 812, a tapered distal portion 814 terminating in an insulated distal apex 816, and a ring-shaped electrode 820 including a conductive material (e.g., Pt, Ir, Au, Ti, Cr, Ni, etc.) and disposed on the tapered distal portion 814. As FIG. 8A shown, the ring-shaped electrode 820 can be located proximal to (or offset or spaced apart from) the distal apex 816. For example, the electrode 820 can be electrically isolated from the distal apex 816 by a distal insulating surface 815a including an insulating material (e.g., SiO2). In some variations, the electrode 820 can also be electrically isolated from the cylindrical body portion 812 by a second distal insulating surface 815b. The electrode 820 can be in electrical communication with a conductive core 840 (e.g., a conductive pathway) extending along the body portion 812 to a backside electrical contact 830 (e.g., made of a Ni / Au alloy) or other electrical bonding region in or on the substrate 802. For example, the body portion 812 can include a conductive core material (e.g., highly doped silicon). As FIG. 8A shown, in some variations, an insulating sheath 813 including an insulating material (e.g., SiO2) can be disposed around (e.g., around a perimeter of) the body portion 812 and extend at least partially through the substrate 802. Thus, the insulating sheath 813 can, for example, help prevent electrical contact between the conductive core 840 and the surrounding substrate 802. The insulating sheath 813 can further extend over the entire surface of the body portion 812. The upper and / or lower surfaces of the substrate 802 can also include a layer of substrate insulator 804 (e.g., SiO2). Thus, the insulation provided by the insulating sheath 813 and / or the substrate insulator 804 can at least partially contribute to the electrical isolation of the microneedle 800, which enables the microneedle 800 to be individually addressable within a microneedle array. Furthermore, in some variations, the insulating sheath 813 extending over the entire surface of the body portion 812 can be used to increase the mechanical strength of the microneedle 800 structure.

[0155] Microneedle 800 can be formed at least in part by suitable MEMS fabrication techniques, such as plasma etching, also known as dry etching. For example, in some variations, insulating sheath 813 around body portion 812 of microneedle can be made by first forming a trench in a silicon substrate from the backside of the substrate by deep reactive ion etching (DRIE), and then filling the trench with a sandwich of SiO2 / poly-Si / SiO2 by low pressure chemical vapor deposition (LPCVD) or other suitable process. In other words, insulating sheath 813 can passivate the surface of body portion 812 of microneedle, and continue as a buried feature in substrate 802 near the proximal portion of microneedle. By primarily comprising silicon compounds, insulating sheath 813 can provide good filling and adhesion to adjacent silicon walls (e.g., walls of conductive core 840, walls of substrate 802, etc.). The sandwich of insulating sheath 813 can further help provide a good match in coefficient of thermal expansion (CTE) with adjacent silicon, thereby advantageously reducing defects, cracks, and / or other thermally induced weaknesses in insulating sheath 813.

[0156] Tapered distal portion can be shaped from the front side of the substrate by isotropic dry etching, and body portion 812 of microneedle 800 can be made by DRIE. Front side metal electrode 820 can be deposited and patterned on the distal portion by specialized photolithography (e.g., e-beam evaporation) that allows metal to be deposited in the desired annular region to obtain electrode 820, without coating distal apex 816. In addition, back side electrical contact 830 of Ni / Au can be deposited by suitable MEMS fabrication techniques (e.g., sputtering).

[0157] Microneedle 800 can have any suitable dimensions. For example, in some variations, microneedle 800 can have a height of about 300 pm to about 500 pm. In some variations, tapered distal portion 814 can have an apex angle of about 60 degrees to about 80 degrees, and an apex diameter of about 1 pm to about 15 pm. In some variations, the surface area of annular electrode 820 can be about 9,000 pm 2 to about 11,000 pm 2 , or about 10,000 pm 2 . FIG. 9 Various dimensions of an exemplary variation of a columnar microneedle having a tapered distal portion and an annular electrode, similar to microneedle 800 described above, are shown.

[0158] FIG. 10A-10F Another example variation of a microneedle 1000 is shown, having a generally columnar body portion extending from a substrate 1002 having an upper / top surface 1004. Microneedle 1000 can be similar to microneedle 800 as described above, except as noted below. For example, as FIG. 10BAs shown, similar to microneedle 800, microneedle 1000 can include a cylindrical body portion 1012, and a tapered distal portion 1014 disposed on the cylinder 1013 and terminating in an insulated distal tip 1016. The cylinder 1013 can be insulated and have a smaller diameter than the cylindrical body portion 1012. Microneedle 1000 can also include a ring electrode 1020 comprising an electrically conductive material and disposed on the tapered distal portion at a location proximal to (or offset or spaced apart from) the distal tip 1016. As FIG. 10A-10F As shown, other elements of microneedle 1000 have similar reference numerals to corresponding elements of microneedle 800.

[0159] However, the electrode 1020 on microneedle 1000 can include a tip contact groove 1022. This contact groove can be configured to facilitate establishing an ohmic contact between the electrode 1020 and the underlying conductive core 1040. In some variations, the shape of the tip contact groove 1022 can include an annular groove formed in the surface of the conductive core 1040 (e.g., into / through the body portion of the microneedle, or otherwise in contact with the conductive path in the body portion) such that when the electrode 1020 material is deposited onto the conductive core 1040, the electrode 1020 with the tip contact groove 1022 can have a stepped profile when viewed from the side. The tip contact groove 1022 can advantageously help provide a margin of error to ensure contact between the electrode 1020 and the underlying conductive core 1040. Any other microneedle variations described herein can also have similar tip contact grooves to help ensure contact between an electrode (e.g., which can be a working electrode, a reference electrode, a counter electrode, etc.) and a conductive path within the microneedle.

[0160] FIG. 11A and 11B Other various dimensions of example variations of cylindrical microneedles having tapered distal portions and ring electrodes similar to microneedle 1000 described above are shown. For example, FIG. 11A and 11BThe variant of the microneedle shown may have a tapered distal portion, which typically has a cone angle of about 80 degrees (or about 78 degrees to about 82 degrees, or about 75 degrees to about 85 degrees) and a cone diameter of about 140 μm (or about 133 μm to about 147 μm, or about 130 μm to about 150 μm). The cone of the tapered distal portion may be arranged on a cylinder such that the total combined height of the cone and cylinder is about 110 μm (or about 99 μm to about 116 μm, or about 95 μm to about 120 μm). The annular electrode on the tapered distal portion may have an outer diameter or base diameter of about 106 μm (or about 95 μm to about 117 μm, or about 90 μm to about 120 μm) and an inner diameter of about 33.2 μm (or about 30 μm to about 36 μm, or about 25 μm to about 40 μm). Measured along the slope of the distal portion of the cone, the length of the annular electrode can be approximately 57 μm (or approximately 55 μm to approximately 65 μm), and the total surface area of ​​the electrode can be approximately 12,700 μm. 2 (or approximately 12,500 μm) 2 Approximately 12,900 μm 2 or approximately 12,000 μm 2 Approximately 13,000 μm 2 ).like FIG. 11B As shown, the electrode may also have a tip contact groove extending around the central region of a cone surrounding the distal conical portion, wherein the contact / contact groove may have a width of about 11 μm (or about 5 μm to about 50 μm, about 10 μm to about 12 μm, or about 8 μm to about 14 μm) and a groove depth of about 1.5 μm (or about 0.1 μm to about 5 μm, or about 0.5 μm to about 1.5 μm, or about 1.4 μm to about 1.6 μm, or about 1 μm to about 2 μm). The microneedle has an insulated distal apex with a diameter of about 5.5 μm (or about 5.3 μm to about 5.8 μm, or about 5 μm to about 6 μm).

[0161] The details of exemplary variations of the microneedle array configuration are further elaborated below.

[0162] As described above, each microneedle in a microneedle array can include an electrode. In some variations, a plurality of different types of electrodes can be included between microneedles in a microneedle array. For example, in some variations, a microneedle array can be used as an electrochemical cell, which can be operated galvanostatically with three types of electrodes. In other words, a microneedle array can include at least one working electrode, at least one counter electrode, and at least one reference electrode. Thus, a microneedle array can include three different electrode types, but one or more of each electrode type can form a complete system (e.g., the system can include multiple different working electrodes). Further, multiple different microneedles can be electrically connected to form an effective electrode type (e.g., a single working electrode can be formed from two or more connected microneedles with working electrode sites). Each of these electrode types can include a metallization layer, and can include one or more coatings or layers on the metallization layer that help facilitate the function of that electrode.

[0163] Generally, a working electrode refers to an electrode where oxidation and / or reduction reactions of interest occur to detect an analyte of interest. The function of a counter electrode is to supply the electrons needed to sustain electrochemical reactions on the working electrode by pulling current (provision) or forcing current (accumulation). The function of a reference electrode is to provide a reference potential for the system; that is, the potential at which the working electrode is biased with reference to the reference electrode. A fixed, time-varying, or at least controlled potential relationship is established between the working electrode and the reference electrode, and within practical limits, no current flows out of or into the reference electrode. Further, to implement such a three-electrode system, an analyte monitoring device can include a suitable potentiostat or electrochemical analog front end to maintain a fixed potential relationship between the working electrode and the reference electrode within the electrochemical system (via electronic feedback mechanisms), while allowing the counter electrode to dynamically swing to the potential needed to sustain the oxidation-reduction reactions of interest.

[0164] A plurality of microneedles (e.g., any of the microneedle variations described herein, each of which can have a working electrode, counter electrode, or reference electrode as described above) can be arranged in a microneedle array. Considerations for how to configure the microneedles include factors such as optimization of insertion force required to penetrate the skin with the microneedle array, electrode signal levels and other performance aspects, manufacturing cost and complexity, and the like.

[0165] For example, a microneedle array can include a plurality of microneedles spaced apart at a predetermined pitch (the distance between the center of one microneedle and the center of its nearest neighboring microneedle). In some variations, the microneedles can be spaced apart at a pitch sufficient to distribute the force applied to the user's skin (e.g., to avoid a "bed of nails" effect) to enable the microneedle array to penetrate the skin. As the pitch increases, the force required to insert the microneedle array tends to decrease, while the depth of penetration tends to increase. However, it has been found that the pitch begins to affect the insertion force only at low values (e.g., less than about 150 pm). Thus, in some variations, the microneedles in a microneedle array can have a pitch of at least 200 pm, at least 300 pm, at least 400 pm, at least 500 pm, at least 600 pm, at least 700 pm, or at least 750 pm. For example, the pitch can be from about 200 pm to about 800 pm, from about 300 pm to about 700 pm, or from about 400 pm to about 600 pm. In some variations, the microneedles can be arranged in a periodic grid, and the pitch can be uniform in all directions and across all areas of the microneedle array. Alternatively, the pitch measured along different axes (e.g., X, Y directions) can be different, and / or some areas of the microneedle array can include a smaller pitch while other areas can include a larger pitch.

[0166] Furthermore, to achieve more consistent penetration, the microneedles can be spaced equidistant from one another (e.g., the same pitch in all directions). To this end, in some variations, the microneedles in a microneedle array can be arranged in a hexagonal configuration as shown in FIGS. 13A-13B and 14A-14J. Alternatively, the microneedles in a microneedle array can be arranged in a rectangular array (e.g., a square array), or in another suitable symmetrical manner. FIG. 12A-12C ,13A-13B and 14A-14J. Alternatively, the microneedles in a microneedle array can be arranged in a rectangular array (e.g., a square array), or in another suitable symmetrical manner.

[0167] Another consideration in determining the configuration of a microneedle array is the total signal level provided by the microneedles. Generally, the signal level of each microneedle in the total number of microneedle elements in the array is the same. However, the signal level can be enhanced by electrically interconnecting a plurality of microneedles in the array together. For example, an array with a large number of electrically connected microneedles is expected to produce a greater signal strength (and thus improve accuracy) compared to an array with fewer microneedles. However, carrying a larger number of microneedles on a carrier sheet will increase the cost of the carrier sheet (assuming a constant pitch), and also require a greater force and / or velocity to insert into the skin. Conversely, a smaller number of microneedles on a carrier sheet can reduce the cost of the carrier sheet, and enable insertion into the skin with a reduced applied force and / or velocity. Furthermore, in some variations, a lower number of microneedles on a carrier sheet can reduce the total footprint area of the carrier sheet, which can result in less unwanted localized edema and / or erythema. Thus, in some variations, a microneedle array including 37 microneedles as shown in FIG. 15A or FIG. 13A-13B a microneedle array including 19 microneedles as shown in FIG. 15B can be utilized. In some variations, a microneedle array including 9 microneedles as shown in FIG. 15C or FIG. 12A-12CThe illustrated microneedle array including 7 microneedles achieves a balance between these factors. However, in other variations, there can be fewer microneedles in the array (e.g., about 5 to about 35, about 5 to about 30, about 5 to about 25, about 5 to about 20, about 5 to about 15, about 5 to about 100, about 10 to about 30, about 15 to about 25, etc.) or there can be more microneedles in the array (e.g., more than 37, more than 40, more than 45, etc.).

[0168] Further, as described in further detail below, in some variations, only a subset of the microneedles in the microneedle array can be active / functional during operation of the analyte monitoring device. For example, a portion of the microneedles in the microneedle array can be inactive / inoperable (e.g., no signal is read from the electrodes of the inactive microneedles). In some variations, a portion of the microneedles in the microneedle array can be activated at some time during operation and remain active / functional for the remainder of the operational life of the device. Further, in some variations, a portion of the microneedles in the microneedle array can additionally or alternatively be deactivated at some time during operation and remain inactive / inoperable for the remainder of the operational life of the device.

[0169] In considering the characteristics of the microneedle array carrier sheet, the carrier sheet size is a function of the number of microneedles in the microneedle array and the microneedle pitch. Manufacturing cost is also a consideration, as smaller carrier sheet sizes will help reduce costs as the number of carrier sheets that can be formed from a given area of a single wafer will increase. Further, smaller carrier sheet sizes are also less prone to brittle fracture due to the relative fragility of the substrate.

[0170] Further, in some variations, microneedles at the periphery of the microneedle array (e.g., near the edge or border of the carrier sheet, near the edge or border of the housing, near the edge or border of an adhesive layer on the housing, along the outer border of the microneedle array, etc.) can be found to have better performance (e.g., sensitivity) as they have better penetration compared to microneedles at the center of the microneedle array or carrier sheet. Accordingly, in some variations, the working electrodes can be disposed mostly or entirely on microneedles located at the periphery of the microneedle array to obtain more accurate and / or precise analyte measurements.

[0171] FIG. 13A and 13B A schematic diagram depicting 37 microneedles arranged in an example variation of a microneedle array 1300 is depicted. For example, the 37 microneedles can be arranged in a hexagonal array with an inter-needle center-to-center pitch of about 750 pm (or about 700 pm to about 800 pm, or about 725 pm to about 775 pm) between the center of each microneedle and the center of its nearest neighbor in any direction. FIG. 13AA schematic diagram depicting an exemplary variant of a microneedle array and a carrier sheet including a microneedle configuration. Exemplary dimensions of the microneedle array and carrier sheet (e.g., about 4.4 millimeters by about 5.0 millimeters) are shown. FIG. 13B

[0172] FIG. 12A 12B A schematic perspective view depicting seven microneedles 1210 arranged in an exemplary variant of a microneedle array 1200. The seven microneedles 1210 are arranged in a hexagonal array on a substrate 1202. As shown, FIG. 12A FIG. 12B As shown, the proximal portions of the microneedles 1210 are conductively connected to respective backside electrical contacts 1230 located on a second surface of the substrate 1202 opposite the first surface of the substrate 1202. FIG. 12C 12D A schematic plan view and side view depicting a microneedle array similar to the microneedle array 1200. As shown, FIG. 12C 12D As shown, the seven microneedles are arranged in a hexagonal array with an inter-needle center-to-center spacing of about 750 pm between the center of each microneedle and the center of its nearest neighbor in any direction. In other variants, the inter-needle center-to-center spacing can be, for example, from about 700 pm to about 800 pm, or from about 725 pm to about 775 pm. The microneedles can have an outer shaft diameter of approximately about 170 pm (or from about 150 pm to about 190 pm, or from about 125 pm to about 200 pm) and a height of about 500 pm (or from about 475 pm to about 525 pm, or from about 450 pm to about 550 pm).

[0173] Furthermore, the microneedle arrays described herein can have a high degree of configurability with respect to the location of working electrodes, counter electrodes, and reference electrodes in the microneedle array. Electronic systems can facilitate this configurability.

[0174] In some variants, a microneedle array can include two or more groups of electrodes distributed in the microneedle array in a symmetric or asymmetric manner, with each group having the same or different number of electrode components depending on the requirements for signal sensitivity and / or redundancy. For example, electrodes of the same type (e.g., working electrodes) can be distributed in the microneedle array in a bilateral symmetric or radial symmetric manner. For example, FIG. 14A ​​​​​A variation of microneedle array 1400A is depicted that includes two symmetric groups of seven working electrodes (WE), labeled “1” and “2”. In this variation, the two working electrode groups are distributed in the microneedle array in a bilateral symmetric fashion. The working electrodes are generally arranged between a central region occupied by three reference electrodes (RE) and a peripheral region occupied by twenty counter electrodes (CE). In some variations, each of the two working electrode groups can include seven working electrodes that are electrically connected between them (e.g., to enhance the sensor signal). Alternatively, only a portion of one or both working electrode groups can include multiple electrodes that are electrically connected between them. As another option, the working electrode groups can include working electrodes that are independent and not electrically connected to other working electrodes. Further, in some variations, the working electrode groups can be distributed in the microneedle array in an asymmetric or random configuration.

[0175] As another example, FIG. 14B A variation of microneedle array 1400B is depicted that includes four symmetric groups of three working electrodes (WE), labeled “1”, “2”, “3”, and “4”. In this variation, the four working electrode groups are distributed in the microneedle array in a radial symmetric fashion. Each working electrode group is adjacent to one of the two reference electrode (RE) components in the microneedle array, and are arranged in a symmetric fashion. The microneedle array also includes counter electrodes (CE) that are arranged around the periphery of the microneedle array, but two electrodes that are not active / inactive or can be used for other features or modes of operation occupy two of the vertices of the hexagon.

[0176] In some variations, only a portion of the microneedle array can include active electrodes. For example, FIG. 14C A variation of microneedle array 1400C is depicted that has 37 microneedles and a reduced number of active electrodes, including four bilaterally symmetrically arranged working electrodes (labeled “1”, “2”, “3”, and “4”), twenty-two counter electrodes, and three reference electrodes. The remaining eight electrodes in the microneedle array are inactive. In FIG. 19C In the depicted microneedle array, each working electrode is surrounded by a group of counter electrodes. The two groups of such working electrode and counter electrode clusters are separated by a row of three reference electrodes.

[0177] As another example, FIG. 14D A variation of microneedle array 1400D is depicted that has 37 microneedles and a reduced number of active electrodes, including four bilaterally symmetrically arranged working electrodes (labeled “1”, “2”, “3”, and “4”), twenty counter electrodes, and three reference electrodes, where the remaining ten electrodes in the microneedle array are inactive electrodes.

[0178] As another example,FIG. 14E A variation of microneedle array 1400E is depicted having 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1", "2", "3", and "4"), eighteen counter electrodes, and two reference electrodes. The remaining thirteen electrodes in the microneedle array are inactive / inactive. The inactive electrodes are arranged along a partial perimeter of the entire microneedle array, thereby reducing the effective size and shape of the active microneedle arrangement to a smaller hexagonal array. In the active microneedle arrangement, the four working electrodes are arranged in a generally radial symmetry, and each working electrode is surrounded by a set of counter electrodes.

[0179] FIG. 14F Another example variation of microneedle array 1400F is depicted having 37 microneedles and a reduced number of active electrodes, including four working electrodes (labeled "1", "2", "3", and "4"), two counter electrodes, and one reference electrode. The remaining thirty electrodes in the microneedle array are inactive / inactive. The inactive electrodes are arranged in two layers around the perimeter of the entire microneedle array, thereby reducing the effective size and shape of the active microneedle arrangement to a smaller hexagonal array centered on the reference electrode. In the active microneedle arrangement, the four working electrodes are arranged in a two-sided symmetry, and the two counter electrodes are equidistant from the central reference electrode.

[0180] FIG. 14G Another example variation of microneedle array 1400G is depicted having 37 microneedles and a reduced number of active electrodes. The active electrodes in microneedle array 1400G are arranged in a similar manner as microneedle array 1400F shown, except that microneedle array 1400G includes one counter electrode and two reference electrodes, and the smaller hexagonal active microneedle array is centered on the counter electrode. In the active microneedle arrangement, the four working electrodes are arranged in a two-sided symmetry, and the two reference electrodes are equidistant from the central counter electrode. FIG. 14F

[0181] FIG. 14H Another example variation of microneedle array 1400H is depicted having 7 microneedles. This microneedle arrangement contains two microneedles assigned as independent working electrodes (1 and 2), a counter electrode group consisting of 4 microneedles, and a single reference electrode. The arrangement of the working electrodes and the counter electrode group are both two-sided symmetrical, and they are equidistant from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., at the outer perimeter of the carrier sheet or array) to take advantage of the location where the working electrodes are expected to have higher sensitivity and overall performance.

[0182] FIG. 14I ​Another example variation of a microneedle array 1400I having 7 microneedles is depicted. The microneedle arrangement includes four microneedles assigned as two independent groups (1 and 2), each group containing two working electrodes; a counter electrode group consisting of two microneedles; and a single reference electrode. The arrangement of working electrodes and counter electrodes are both bilaterally symmetric, with equal distance from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., arranged at the outer periphery of the carrier sheet or array) to take advantage of the location where working electrodes are expected to have higher sensitivity and overall performance.

[0183] FIG. 14J Another example variation of a microneedle array 1400J having 7 microneedles is depicted. The microneedle arrangement includes four microneedles assigned as independent working electrodes (1, 2, 3, and 4), a counter electrode group consisting of two microneedles, and a single reference electrode. The arrangement of working electrodes and counter electrodes are both bilaterally symmetric, with equal distance from the central reference electrode. In addition, the working electrodes are arranged as far away from the center of the microneedle array as possible (e.g., arranged at the outer periphery of the carrier sheet or array) to take advantage of the location where working electrodes are expected to have higher sensitivity and overall performance.

[0184] While FIG. 14A-14J While example variations of microneedle array configurations are illustrated, it should be understood that these figures are not limiting and that other microneedle configurations (including different numbers and / or distributions of working electrodes, counter electrodes, and reference electrodes, as well as different numbers and / or distributions of active electrodes and inactive electrodes, among others) can be suitable for other variations of microneedle arrays.

[0185] As FIG. 1 In some variations, the analyte monitoring device 110 can be applied to the skin using a suitable applicator 160, as shown. The applicator can be configured, for example, to push the analyte monitoring device 110 against the user's skin such that the microneedle array 140 can be inserted into the skin (e.g., to a desired target depth) and the one or more adhesive layers adhere to the skin to securely hold the analyte monitoring device 110 in place.

[0186] The applicator can include an actuatable housing (also referred to as an actuator and / or a housing) that includes a housing body defining a cavity within it. The housing body has a distal opening, and components of the applicator can be located and / or positioned within the cavity of the housing body. The applicator components are aligned and configured to securely hold the analyte monitoring device 110 such that the analyte monitoring device 110 is positioned for insertion of the microneedle array 140 into the skin (e.g., the microneedle array is positioned such that the tips of the microneedles are facing in a distal direction). Further, the applicator components are aligned and configured to move and release the analyte monitoring device 110 at a speed that allows the microneedles of the microneedle array 140 to insert into the skin with sufficient force.

[0187] In some variations, the applicator can include a housing body, a cuff assembly, a transfer piece, and a removable base (also referred to as a base). The housing body, the cuff assembly, the transfer piece, and the base can be interengaged by one or more releasable coupling features and / or engagement features. The base can be released from engagement with the housing body such that the cuff assembly and the transfer piece are aligned and positioned in a configuration in which the analyte monitoring device 110 held by the transfer piece is ready for insertion into the skin. The transfer piece and the cuff assembly can be individually translatable relative to the housing body. In an application procedure, actuation of the housing body (e.g., manually actuated by a user, or with an additional external actuator) causes the transfer piece and the analyte monitoring device 110 to move at a speed that enables the microneedle array 140 to be inserted into the skin of the user with a force that enables the microneedles of the microneedle array 140 to be inserted into the skin.

[0188] The housing, the cuff assembly, and the transfer piece can be axially aligned (e.g., concentric) and / or nested and / or telescopically arranged. The transfer piece can releasably hold (e.g., grasp, encase, or otherwise carry) the analyte monitoring device 110. The applicator can transition from a first “collapsed” configuration to a second “extended” configuration, and to a third “released” configuration. In the collapsed configuration, the components of the applicator are locked relative to one another such that the engagement between the components of the applicator is fixed, the components cannot move relative to one another, and the analyte monitoring device 110 cannot be deployed. In the collapsed configuration, the base is engaged with the housing. In the extended configuration, the components of the applicator are arranged and configured such that the analyte monitoring device can be deployed (e.g., released) from the applicator in response to actuation of the housing. The base is removed, and the transfer piece is moved to a cocked position in the extended configuration. In the released configuration, the analyte monitoring device 110 is released from the applicator and inserted into the skin of the user. Each of the configurations and the transitions between them are described in detail below.

[0189] The cuff assembly can be a single component, or in certain variations, can include two or more components to form the cuff assembly. For example, the cuff and the friction ring can be joined and / or locked together, as further described herein.

[0190] In some variations, in the retracted configuration, the analyte monitoring device 110 remains within the transfer member, the distal edge of the cuff is in the proximal-most position, and the transfer member is in the proximal-most position. In the extended configuration, the distal edge of the cuff is in the distal-most position, and the transfer member is in the intermediate position. In the released configuration, the analyte monitoring device 110 is released from the transfer member, the distal edge of the cuff is in the intermediate position, and the transfer member is in the distal-most position.

[0191] The housing can include a first retention surface or feature that is releasably coupled with the coupling member of the cuff assembly. The housing can also include a second retention surface or feature that is releasably engaged with the engagement member of the transfer member. In response to actuation of at least a portion of the housing toward the transfer member (e.g., the applicator can be compressed into place, such as against a skin surface of a user), the first retention surface of the housing can decouple from the coupling member of the cuff assembly, which can allow the engagement between the second retention surface of the housing and the engagement member of the transfer member to be released. During the axial movement of the transfer member in response to the actuation of the housing, the transfer member can engage at least one transfer member bending surface (e.g., a hard stop) of the cuff assembly. The engagement of the transfer member with the transfer member bending surface can cause the transfer member to bend radially outward, thereby causing the analyte monitoring device 110 to be released from the transfer member.

[0192] Additionally, the applicator can include one or more biasing elements (e.g., springs) for urging adjacent components distally. For example, in some variations, the applicator can include a first biasing element disposed between the housing and the cuff assembly. The first biasing element can be loaded to store potential energy prior to actuation of the housing (e.g., the first biasing element can include a compression spring that is pre-compressed prior to actuation of the housing). Upon actuation of the housing during the application procedure, the first biasing element can provide a force to the cuff assembly that causes the first retention surface of the housing to decouple from the coupling member of the cuff assembly. Additionally or alternatively, the applicator can include a second biasing element disposed between the housing and the delivery member. The second biasing element can be loaded to store potential energy prior to actuation of the housing (e.g., the second biasing element can include a compression spring that is pre-compressed prior to actuation of the housing). When the delivery member is decoupled from the housing as a result of actuation of the housing during the application procedure, the energy stored in the loaded second biasing element can be transferred to the delivery member, driving the analyte monitoring device at a suitable application force (e.g., a suitable skin penetration for a microneedle array). The combination of the two biasing elements for deploying the analyte monitoring device 110 allows for control of the actuation force and the speed at which the delivery member moves (e.g., the impact velocity) in response to actuation of the housing. The dual biasing element design allows for control of the impact velocity independent of the force used for actuation. In some variations, the force provided by the first biasing element to the cuff assembly can range from about 5 Newtons to about 45 Newtons. In some variations, the residual force provided by the second biasing element to the delivery member can range from about 5 Newtons to about 45 Newtons. The impact velocity can range from about 2 meters / second to about 10 meters / second. The force provided by the first and second biasing elements and the resulting impact velocity can be controlled by adjusting the compression and characteristics of the biasing elements.

[0193] The components of the applicator can be made using any suitable manufacturing process, including injection molding, casting, 3D printing, machining techniques (e.g., using a mill or lathe), etc.

[0194] FIG. 15A-FIG. 15D An example variation of an applicator 1500 for an analyte monitoring device (e.g., analyte monitoring device 110) is depicted. FIG. 15A and 15B is a side view of the applicator 1500, FIG. 15C is a top perspective view of the applicator 1500, and FIG. 15D is a bottom perspective view of the applicator 1500. FIG. 15A and FIG. 15B depicts the applicator 1500 in a retracted configuration, with the base 1550 engaged with the housing covered by the outer enclosure 1570.

[0195] FIG. 15C and FIG. 15DAn exploded view of the applicator 1500 is depicted. As FIG. 15C and FIG. 15D shown, the applicator 1500 includes a housing 1510, a ferrule 1520, a friction ring 1530, a transfer 1540, and a base 1550. The housing 1510 includes a housing body defining a cavity therein. The housing body has a distal opening, and components of the applicator can be located and / or positioned within the cavity of the housing body and / or connected to the cavity of the housing body through the distal opening.

[0196] The friction ring 1530 is axially aligned with the ferrule 1520 and is configured to be nested and arranged (e.g., telescopically arranged) within the ferrule 1520. The ferrule 1520 and the friction ring 1530 are axially aligned with the cavity of the housing body and are configured to be nested and arranged within the cavity of the housing body. The transfer 1540 is axially aligned with the nested arrangement of the ferrule 1520 and the friction ring 1530 in the cavity of the housing body and is configured to be nested and arranged within the nested arrangement.

[0197] The applicator 1500 also includes a base 1550 arranged to engage with the housing body at the distal opening of the housing body. A locking member 1560, an outer enclosure 1570, and a top plug 1580 are also provided. In some variations, the outer enclosure 1570 and / or the top plug 1580 are optional and need not be included in the applicator 1500 for operation.

[0198] As FIG. 15C and FIG. 15D further shown, a first biasing element 1582 (e.g., a first compression spring) can be arranged between the housing 1510 and the ferrule 1520, and a second biasing element 1584 (e.g., a second compression spring) can be arranged between the housing 1510 and the transfer 1540.

[0199] FIG. 15E and FIG. 15F various aspects of the transfer 1540 and the analyte monitoring device 110 relative to one another are shown in exploded view and perspective view, respectively. As FIG. 15E and FIG. 15F shown, the analyte monitoring device 110 with the attached microneedle enclosure 500 can be held in the transfer 1540, and the microneedle array 140 (enclosed by the microneedle enclosure 500 in the view of FIG. 15E and FIG. 15F ) is in a distal direction. When the transfer 1540 is arranged in the cavity of the housing body, the analyte monitoring device 110 is located at the distal end.

[0200] The base 1550 is removably coupled to the housing body to completely enclose the analyte monitoring device 110 within the cavity defined by the housing body (e.g., to maintain the sterility of the device 110 prior to application, as further described herein). The base 1550 is a removable distal cap or lid that releasably engages with the housing body when the applicator is in a retracted configuration. The base 1550 is coupled to a microneedle housing 500 that provides a sterile environment for the microneedle array 140. In some variations, the microneedle housing 500 is removed along with the base 1550 when the base 1550 is removed from the housing body, thereby allowing the microneedle array 140 to be accessed through a distal opening in the housing body. Additional details are provided herein.

[0201] FIG. 16A , FIG. 16B , FIG. 16C and FIG. 16D Several aspects of the transport component 1540 are described in more detail. FIG. 16A This is a perspective view of transport component 1540. FIG. 16B It is a bottom view. FIG. 16C It is a side view. FIG. 16D It is along FIG. 16C The image shows a cross-sectional side view along line AA. The conveyor 1540 is configured to hold the analyte monitoring device 110 when the applicator 1500 is in a contracted and extended configuration. The conveyor 1540 is configured to deploy the analyte monitoring device 110 in response to actuation of the housing 1510, with the speed and force required to insert the microneedles of the microneedle array 140 into the user's skin. In the applicator's released configuration, the analyte monitoring device 110 is released from the conveyor 1540.

[0202] As shown in the figure, the conveyor 1540 includes a base portion 1610 and a conveyor shaft 1630. The conveyor shaft 1630 defines an inner cavity 1632 in which a second biasing element 1584 is disposed.

[0203] The transfer member 1540 may include engaging members or features for releasably engaging with the transfer member retaining surface or features of the housing 1510. The engaging members or features may be formed at one or more portions of the outer periphery of the transfer member axis 1630 and may be configured to releasably engage with the transfer member retaining surface of the housing 1510. In some variations, such as FIG. 16CAs shown, the engagement member can include a distal surface 1636 of the shelf 1634. The shelf 1634 can be a portion of the transfer member shaft 1630 that extends horizontally outward from the transfer member shaft 1630. The shelf 1634 can have a span (e.g., width or diameter) that is greater than a span (e.g., width or diameter) of the transfer member shaft 1630, where the span is measured in a direction that is orthogonal to an axial arrangement direction of the transfer member 1540 within the cavity of the housing body. The distal surface 1636 can be a surface, such as a shoulder, that extends between the shelf 1634 and the transfer member shaft 1630. In some variations, the distal surface 1636 can be an angled surface. In some variations, the distal surface 1636 can be flat or substantially flat. As described further herein, the distal surface 1636 releasably engages with the housing 1510 at the transfer member retention surface.

[0204] The base portion 1610 distal to the transfer member shaft 1630 includes one or more flexible vanes 1612 extending from the transfer member shaft 1630, one or more flexible support petals 1614 extending from the transfer member shaft 1630, and one or more tracking protrusions 1616 extending from an outer sidewall of the one or more flexible vanes 1612.

[0205] The configuration or orientation of the flexible vanes 1612 defines a configuration of the transfer member 1540 (e.g., a carry configuration and a release configuration), as described herein. The flexible vanes 1612 define a receptacle 1640 in which the analyte monitoring device 110 can be housed. For example, as shown in FIGS. 16A and 16B, the flexible vanes 1612 can define a substantially cylindrical receptacle 1640 in which the analyte monitoring device 110 can be housed. FIG. 16A and FIG. 16B As shown, each flexible vane 1612 includes an arcuate or curved member extending from a flexible connection member that is attached at its proximal end to the transfer member shaft 1630. The flexible connection member allows the flexible vane 1612 to flex relative to the transfer member shaft 1630. For example, in some variations, the flexible vane 1612 is a cantilevered arm that can flex radially outward. The flexible vanes 1612 can be arranged circumferentially about the transfer member shaft 1630 to define a receptacle 1640 for supporting / encasing the analyte monitoring device 110 that covers a region of access to the analyte monitoring device 110. As shown in FIGS. 16A and 16B, the flexible vanes 1612 can define a substantially cylindrical receptacle 1640 in which the analyte monitoring device 110 can be housed. FIG. 16A and FIG. 16BAs shown, the receiving portion 1640 can be substantially circular. When the flexible blade 1612 is in its natural, unbent state, the conveyor 1540 is in a supporting configuration, in which the analyte monitoring device 110 is supported or held in the receiving portion 1640. In the supporting configuration, the analyte monitoring device 110 is held in the receiving portion 1640 due to the engagement of the inner wall of the flexible blade 1612 with the periphery of the analyte monitoring device 110. For example, external pressure can be applied to the flexible blade 1612, causing the conveyor 1540 to change to a release configuration. In the release configuration, the analyte monitoring device 110 is not held by the flexible blade 1612, and the analyte monitoring device 110 is able to be released from the receiving portion 1640. The external pressure can be provided at least partially by the second biasing element 1584. For example, during the application of the procedure, when the housing 1510 is actuated, the transmitter 1540 moves axially downward through a concentric (e.g., telescopic) arrangement within the clamp 1520, and the second biasing element 1584 is compressed within the cavity 1632. During the axial movement of the transmitter 1540, a tracking protrusion 1616 extending from the outer wall of the flexible blade 1612 of the transmitter 1540 engages and interferes with the transmitter bending surface of the clamp 1520 (e.g., a hard stop). The transmitter bending surface of the clamp 1520 prevents the axial movement of the transmitter 1540, and the energy stored in the second biasing element 1584 is transferred to the transmitter 1540, causing the flexible blade 1612 to bend radially outward to apply a suitable force to push out the analyte monitoring device 110 (e.g., for suitable insertion of the microneedle array 140 into the user's skin). The flexible blade 1612 is constructed similarly to and / or analogously to a collet configuration, in which the collet arms are radially inwardly biased and engage and retain the component. At the ends of the load path, the collet arms are released from their biased state, thereby disengaging the component.

[0206] In some variations, each flexible blade 1612 may also include one or more optional connecting features arranged at the distal end of the flexible blade 1612 and configured to help enclose the analyte monitoring device 110. For example, as FIG. 16B and FIG. 16D As shown, at least one flexible blade 1612 may include a flange 1622 or other protrusion or flange-like support surface at the distal end of the arcuate or curved member of the flexible blade 1612. The flange 1622 or other protrusion or flange-like support surface may extend inward at the distal end to help provide stable support for the distal surface of the analyte monitoring device 110.

[0207] In some variations, each flexible support petal 1614 is a tab-like member extending from a flexible connecting member that is attached at its proximal end to the transfer member shaft 1630. The flexible support petals 1614 can be arranged circumferentially around the transfer member shaft 1630 in an alternating configuration with the flexible petals 1612. Each flexible support petal 1614 can have a rounded or curved distal surface to hold and / or support and / or stabilize a proximal surface of the analyte monitoring device 110. For example, in some variations, a portion of the proximal surface of the analyte monitoring device 110 fits snugly within an arcuate configuration formed by the distal surface of the flexible support petal 1614.

[0208] Each flexible support petal 1614 can also include one or more optional coupling or clamping features. For example, a support clamp 1624 in the form of a tab-like protrusion or extension can be positioned at the distal end of one or more flexible support petals 1614. The support clamp 1624, together with the rounded or curved distal surface of the flexible support petal 1614, helps to stabilize and hold the analyte monitoring device 110.

[0209] The flange 1622 and / or the clamp member 1624 provide additional support for encasing or holding the analyte monitoring device 110 when the analyte monitoring device 110 is placed in the receptacle 1640. The engagement between the circumferential edge of the analyte monitoring device 110 and the flange 1622 and / or the engagement between the proximal surface of the analyte monitoring device 110 and the clamp member 1624 help to provide additional stability of the analyte monitoring device 110 within the receptacle 1640 when the transfer member 1540 is in the carrying configuration. When the flexible petals 1612 are flexed radially outward (in the release configuration of the transfer member 1540), the flange 1622 does not engage the analyte monitoring device 110 and thus does not provide additional stability to the analyte monitoring device 110 and / or does not prevent its release.

[0210] Although the transfer member 1540 is shown as having four flexible petals 1612 and four flexible support petals 1614, in other variations, the transfer member 1540 can have any suitable number of flexible petals 1612 (e.g., one, two, three, five, six, or more) and any suitable number of flexible support petals 1614 (e.g., one, two, three, five, six, or more). In some variations, the flexible support petals 1614 are not included. In some variations, the number of flexible petals 1612 can be different from the number of flexible support petals 1614. For example, the transfer member 1540 can include fewer or more flexible support petals 1614 than flexible petals 1612.

[0211] While the illustrated transfer member 1540 has flexible leaves 1612 that are substantially the same in size and shape, in other variations, one or more flexible leaves 1612 can be different in size and shape from one or more other flexible leaves 1612. For example, the transfer member 1540 can include two such flexible leaves 1612 that have a longer circumference than the other two flexible leaves 1612. Similarly, while the transfer member 1540 is illustrated as having flexible support petals 1614 that are substantially the same in size and shape, in other variations, one or more flexible support petals 1614 can be different in size and shape from one or more other flexible support petals 1614.

[0212] While the illustrated receptacle 1640 has a circular or substantially circular footprint formed by the shape and configuration / conformation of the flexible leaves 1612 and the flexible support petals 1614, the receptacle 1640 can define a footprint of other shapes, such as square, oval, rectangular, etc., to account for the shape of the analyte monitoring device 110. The flexible leaves 1612 and the flexible support petals 1614 can have different configurations / conformations (e.g., curvatures, sizes, shapes, etc.) to provide retention and release of analyte monitoring devices of any shape. In some variations, the curvature of the flexible support petals 1614 is very similar to the curvature of the proximal surface of the analyte monitoring device, such that the flexible support petals 1614 wrap around the proximal surface.

[0213] Referring to FIG. 16E and 16FFIG. 16B shows additional features of the transport 1540 in a bottom perspective view and a bottom view, respectively. In some variations, a gripping layer 1650 can be disposed on the distal surfaces of the flexible vane 1612, the flexible support petal 1614, and the transport shaft 1630. The gripping layer 1650 can be an elastomeric layer that is deposited and / or applied to provide additional gripping capability between the analyte monitoring device 110 and the distal surfaces of the flexible vane 1612, the flexible support petal 1614, and / or the transport shaft 1630. In some variations, one or more proximal surfaces of the analyte monitoring device 110 can be a smooth or substantially smooth surface, and the incorporation of the gripping layer 1650 helps to retain the analyte monitoring device 110 in the receptacle 1640 defined by the flexible vane 1612. In some variations, the gripping layer 1650 is disposed on one or more distal surfaces of the flexible vane 1612, the flexible support petal 1614, and / or the transport shaft 1630 that contact the analyte monitoring device 110 when the analyte monitoring device 110 is retained in the receptacle 1640. In some variations, the gripping layer 1650 is uniformly distributed. In some variations, the gripping layer 1650 is not uniformly distributed. In some variations, the gripping layer 1650 is disposed at one or more contact points between the analyte monitoring device 110 and the distal surfaces of the flexible vane 1612, the flexible support petal 1614, and / or the transport shaft 1630.

[0214] FIG. 16G and FIG. 16H FIGS. 16C and 16D show aspects of the transport 1540 with the shelf 1634 retrofitted in a side view and a side cutaway view, respectively. Additional aspects and features of the transport 1540 can be the same as shown and described with reference to FIGS. 16A and 16B. FIGS. 16A-16F

[0215] ​In some variations, the shelf 1634 has a proximal surface 1638. The proximal surface 1638 can be a surface that extends between the shelf 1634 and the transfer member shaft 1630, such as a shoulder. In some variations, the proximal surface 1638 can be an angled surface. In some variations, the proximal surface 1638 can be flat or substantially flat. In some variations, the proximal surface 1638 of the shelf 1634 can function as a transfer member lock feature. For example, it can be desirable to incorporate a feature that prevents the transfer member 1540 from being reloaded such that the applicator 1500 cannot be moved from the released configuration to the extended configuration. This can be desirable in the case of a sterile and / or unknown condition of the analyte monitoring device 110. For example, if the analyte monitoring device 110 has been released from the applicator 1500, the microneedle array 140 or other components of the analyte monitoring device 110 can be damaged. In response to the axial movement of the transfer member 1540 toward the proximal end of the housing 1510 after the transfer member 1540 disengages the housing 1510 at the transfer member retention surface, the axial movement of the transfer member 1540 is stopped by the distal end of the transfer member retention surface. In particular, the proximal surface 1638 will abut the distal end of the transfer member retention surface, thereby preventing the axial movement of the transfer member 1540 toward the proximal end of the housing 1510. The distal end of the transfer member retention surface can be a flat or substantially flat surface to prevent the proximal surface 1638 from pushing past the transfer member retention surface.

[0216] In some variations (e.g., the variations shown and described), the applicator 1500 can be reloaded and / or reused. For example, the transfer member 1540 is reloadable to allow the transfer member 1540 to move axially toward the proximal end of the housing 1510 such that the applicator components can be reengaged into the extended configuration. FIGS. 16A-16D

[0217] In some variations, alternative and / or additional transfer member lock features can be incorporated. In one variation, a spring clip feature nests within the transfer member shaft 1630 in a retention post within the transfer member shaft 1630. The distal end of the spring-loaded finger is bent inward to be retained by the retention post. The proximal end of the spring-loaded finger is retained at the proximal end of the cavity of the housing body. When the applicator 1500 transitions to the extended configuration and the transfer member 1540 moves toward the distal end of the housing body, the retention post moves with the transfer member 1540 and the spring-loaded finger expands to a larger radial configuration. If an attempt is made to reload or reposition the transfer member (e.g., move the transfer member 1540 toward the proximal end of the housing body), the spring-loaded finger in the larger radial configuration forms a blocking surface against the transfer member 1540.

[0218] ​In another variation, a locking post is positioned within the transfer member shaft 1630. The locking post includes a spring-loaded finger at a distal end that engages with an inner surface feature of the transfer member shaft 1630. At a proximal end, the locking post engages within a footprint defined by a locking arm extending from a proximal end of the cavity of the housing body. Engagement of the locking post within the footprint defined by the locking arm causes the locking arm to deflect outward. As the applicator 1500 is turned to the extended configuration and the transfer member 1540 moves toward the distal end of the housing body, the locking post moves with the transfer member 1540 and the locking arm deflects inward to a natural, un-bent state. The distal end of the locking arm provides a blocking surface against the transfer member 1540 as an attempt is made to reload or reposition the transfer member.

[0219] FIGS. 17A-17E Various aspects of the ferrule 1520 are depicted in greater detail. FIG. 17A A top perspective view of the ferrule 1520 is provided, FIG. 17B is a bottom view, FIG. 17C is a top view, FIG. 17D is a first side and corresponding side cutaway view, FIG. 17E is a second side and corresponding side cutaway view.

[0220] The ferrule 1520 is disposed in a cavity defined by the housing body and is configured to hold the applicator 1500 in a retracted configuration when the base 1550 is engaged with the housing 1510 (where the position of the housing 1510 and the position of the transfer member 1540 are fixed relative to one another). The ferrule 1520 is also structured to disengage the base 1550 from the housing 1510 and transition the applicator 1500 to an extended configuration upon depression of the lockout member 1560. The ferrule 1520 interacts with and engages the friction ring 1530 to transition the transfer member 1540 to a cocked position of the extended configuration, as further described herein. The transfer member 1540 can be substantially axially aligned and nested within the ferrule 1520, and the transfer member 1540 can be axially moved within the ferrule 1520. The ferrule 1520 is used to disengage the analyte monitoring device 110 from the transfer member 1540 when the housing 1510 is actuated.

[0221] As FIG. 17A shown, the ferrule 1520 is a tubular structure having a sidewall and a lumen 1720 extending through the sidewall. The ferrule 1520 has a proximal opening and a distal opening. The cocking ring 1530 and the transfer member 1540 are axially aligned and axially move within the lumen 1720 through the proximal opening and / or the distal opening.

[0222] In some variations, the collar 1520 is generally cylindrical, having a circular or substantially circular cross-section along a plane perpendicular to the height of the collar 1520. In some variations, the collar 1520 can have other configurations. For example, the collar 1520 can have a square, rectangular, or elliptical cross-section. The effective inner diameter or internal span between opposing sidewalls can be uniform along the height of the collar 1520. In some variations, the effective inner diameter or internal span of the collar 1520 can vary slightly along its height. The upper shoulder 1722 is located at the proximal end of the collar 1520 along the proximal opening, and the bottom flange 1732 is located at the distal end of the collar 1520 along the distal opening.

[0223] The collar 1520 includes retention walls 1712 formed on the outer sidewall, which generally extend along the height of the collar 1520 at locations corresponding to respective locking members 1560. As shown, in some variations, the collar 1520 has two retention walls 1712 corresponding to two locking members 1560. In some variations, the collar 1520 has fewer or more retention walls 1712 and corresponding locking members 1560. For example, in some variations, there can be one retention wall 1712 and one locking member 1560. Each retention wall 1712 is defined by a retention lip 1714 extending around at least a portion of the outer perimeter of the retention wall 1712. Each retention wall 1712 can be sized and shaped to generally correspond to the outer perimeter of the locking member 1560, such that the retention lip 1714 closely conforms to and / or aligns with the outer perimeter of the movable locking member 1560. The outer exposed surface of the retention wall 1712 can be flat or substantially flat. In some variations, the outer curvature of the collar 1520 forms the outer exposed surface of the retention wall 1712.

[0224] The top edge of the retention lip 1714 can engage the upper edge of the respective locking member 1560. In the collapsed configuration of the applicator 1500, the locking member 1560 is positioned within the retention wall 1712 such that the upper edge of the locking member 1560 is engaged beneath the top edge of the retention lip 1714, thereby preventing downward movement of the collar 1520 relative to the housing 1510. When the locking member 1560 is depressed, the vertical movement of the collar 1520 is no longer impeded as the locking member 1560 is removed from engagement with the top edge of the retention lip 1714. Further details are described herein.

[0225] The rotational alignment of the conveyor 1540 within the sleeve 1520 can be guided by one or more tracking features. These one or more tracking features can also guide axial movement of the conveyor 1540 within the sleeve 1520. For example, the sleeve 1520 may include one or more tracks 1716 extending along at least a portion of the height of the sleeve 1520, within which one or more tracking protrusions 1616 on the conveyor 1540 can travel. Tracks 1716 may include, for example... FIG. 17A The shown opening slot, or other suitable structure (e.g., a recessed groove or channel) on the tracking protrusion 1616 on the conveyor 1540, can slidably engage. The track 1716 can also be configured to receive other suitable types of tracking features on the conveyor 1540 (e.g., ball bearings). The clamp 1520 and the conveyor 1540 can include any suitable number of tracking features (e.g., one, two, three, four, or more), and the tracking features can be circumferentially distributed in an equal or unequal manner. For example, four tracking features can be evenly distributed around the conveyor 1540 and clamp 1520 at 90-degree intervals. In some variations, two tracking features can be evenly distributed at 180-degree intervals or directly opposite each other, three tracking features can be evenly distributed at 120-degree intervals, and so on.

[0226] Each track 1716 may terminate at its bottom end with a conveyor bending surface 1718. The conveyor bending surface 1718 may be part of the bottom surface of the sleeve 1520 or the bottom flange 1732, or another shoulder-shaped surface serving as a stop for the axial movement of the conveyor 1540, to help the flexible blades 1612 of the conveyor 1540 bend radially outward. For example, the conveyor bending surface 1718 of each track 1716 prevents the conveyor 1540 from moving further beyond the bottom edge of the sleeve 1520.

[0227] The upper shoulder 1722 of the clamp 1520 may include feature structures for engaging and locking to the friction ring 1530. In the contracted configuration of the applicator 1500, the friction ring 1530 is retracted within the lumen 1720 of the clamp 1520. In the transition from the contracted to the extended configuration, the friction ring 1530 extends and / or protrudes from the proximal opening of the clamp 1520 at its proximal end. In the contracted configuration of the applicator 1500, the retracted arrangement of the friction ring 1530 within the clamp 1520 provides a compact overall height for the applicator 1500. In some variations, the friction ring 1530 is not retracted within the clamp 1520, resulting in a higher applicator height in the retracted configuration. In some variations, the friction ring 1530 and the clamp 1520 are not separate components.

[0228] A shoulder formed circumferentially around the top edge of the cuff 1520 can ensure engagement of the friction ring 1530 with the cuff 1520. In some variations, a portion of the upper shoulder 1722 can include a ledge 1724 with a pair of guide walls 1726. The ledge 1724 can be a flat or substantially flat surface that extends outward from a portion of the upper shoulder 1722, such that the ledge 1724 extends over a corresponding portion of the lumen 1720. The two guide walls 1726 can be disposed at either end of the ledge 1724, with the guide walls 1726 including a vertically extending member that extends upward from the ledge 1724 or from near the ledge 1724. The ledge 1724 provides a flat surface for engaging the flexible tab of the friction ring 1530, and the pair of guide walls 1726 secure the flexible tab on the ledge 1724 by preventing rotational movement of the friction ring 1530. For example, the pair of guide walls 1726 are positioned at either end of the ledge 1724 to lock the flexible tab in place on the ledge 1724. The cuff 1520 can include more than one engagement and locking feature for ensuring engagement with the friction ring 1530, and the engagement and locking features can be distributed circumferentially around the upper shoulder 1722 in equal or unequal fashion. For example, as shown in FIGS. 17A-17C, three ledges 1724 with corresponding pairs of guide walls 1726 are evenly distributed around the upper shoulder 1722 120 degrees apart from one another. In some variations, four ledges 1724 with corresponding pairs of guide walls 1726 can be evenly distributed 90 degrees apart from one another, two ledges 1724 with corresponding pairs of guide walls 1726 can be evenly distributed 180 degrees apart from one another or directly opposite one another, and so on. FIG. 17A , 17B and 17C, three ledges 1724 with corresponding pairs of guide walls 1726 are evenly distributed around the upper shoulder 1722 120 degrees apart from one another. In some variations, four ledges 1724 with corresponding pairs of guide walls 1726 can be evenly distributed 90 degrees apart from one another, two ledges 1724 with corresponding pairs of guide walls 1726 can be evenly distributed 180 degrees apart from one another or directly opposite one another, and so on.

[0229] The underside 1728 of the upper shoulder 1722 can also interface with the friction ring 1530. For example, the underside 1728 can interface with a portion of the circumferential edge of the friction ring 1530 to maintain the axial position of the cuff 1520 with the friction ring 1530. Additional details related to engagement and locking are further described herein.

[0230] The outer sidewall of the cuff 1520 can have features that interface with the base 1550. For example, a base retention surface 1730 can be formed at one or more portions of the cuff 1520 around the outer circumference and proximate or at the distal end of the cuff 1520. The base retention surface 1730 can be a rib that protrudes from the outer sidewall of the cuff 1520 and can be configured to provide a retention surface for one or more members of the base 1550, as further described herein.

[0231] FIG. 17F and FIG. 17G various aspects of the cuff 1520 with a varying bottom flange 1732 are shown in bottom and side views, respectively. Additional aspects and features of the cuff 1520 can be as described with reference to the cuff 1520 of FIGS. 16A-16C.FIGS. 17A-17E The same as shown and described. As FIG. 17F and FIG. 17G The bottom flange 1732 has an increased surface area compared to the bottom flange shown in, for example, FIGS. 17A-17C During actuation of the applicator 1500, the distal end of the bottom flange 1732 is the contact area that is in contact with the user’s skin at the insertion site of the analyte monitoring device 110. The increase in surface area of the bottom flange 1732 spreads the force applied during actuation, making the application process a more comfortable experience for the user. With a bottom flange having a smaller surface area (e.g., 17A-17C), the force applied during actuation is concentrated in a smaller area, resulting in a more pronounced feeling of force at the distal end of the cuff 1520 by the user.

[0232] The bottom flange 1732 with increased surface area has cutouts 1734 formed therethrough for accommodating the arms of the base 1550, as described herein.

[0233] The bottom flange 1732 creates a contact surface area for the insertion of the microneedle array 140 of the analyte monitoring device 110. When the applicator 1500 is in the extended configuration, the contact surface area, along with the actuation force required to actuate the housing body, causes the user’s skin to bulge out within the perimeter of the bottom flange 1732 distally of the microneedle array 140. When the skin is bulged (in some variations, approximately 3-6 mm depending on skin type), the skin is stretched and taut, providing a preferred insertion site for the microneedle array, as the stretched / taut skin improves insertion efficiency and consistency. The bulged / domed convex shape of the skin reduces the well-known nail bed effect that can occur with standard microneedle insertion. The result is that the microneedles in the center of the microneedle array can penetrate first, followed by the microneedles around the perimeter of the microneedle array, resulting in a consistent and efficient insertion.

[0234] FIGS. 18A-18D Various aspects of the friction ring 1530 are depicted in more detail. FIG. 18A A first top perspective view of the friction ring 1530 is provided, FIG. 18B A second top perspective view is provided, FIG. 18C A first bottom perspective view is provided, FIG. 18D A second bottom perspective view is provided.

[0235] The friction ring 1530 has an annular structure, concentrically and axially arranged within the clamp 1520, and extends from the clamp 1520 for application of the analyte monitoring device 110. In the retracted configuration of the applicator 1500, the friction ring 1530 retracts within the clamp 1520. The friction ring 1530 includes a connecting member that prevents the launch of the conveyor 1540 until the base 1550 is removed. During the transition from the retracted to the extended configuration of the applicator 1500, and during the removal of the base 1550, the clamp 1520 moves axially toward the distal opening of the housing body, causing the friction ring 1530 to extend and / or protrude from the proximal opening of the clamp 1520 and lock within the clamp 1520. During actuation of the housing 1510, the friction ring 1530 and the clamp 1520 are locked together as a single component and serve to disengage the analyte monitoring device 110 from the conveyor 1540. The conveyor 1540 can be substantially axially aligned and nested within the friction ring 1530, and the conveyor 1540 can move axially within the friction ring 1530.

[0236] like FIGS. 18A-18D As shown, friction ring 1530 has an annular core that defines a friction ring cavity 1810 extending through the annular core. A transmission member 1540 is axially aligned within the friction ring cavity 1810 and moves within it. The outer wall of the annular core is axially aligned with and moves within the sleeve 1520, and at least partially extends out of the sleeve 1520.

[0237] The clamp 1520 can be locked to the friction ring 1530 by one or more engaging and locking features. For example, the friction ring 1530 may include one or more features that engage and lock with a corresponding feature of the clamp 1520. In some variations, the engaging and locking features may be arranged circumferentially around the annular core of the friction ring 1530. For example, a flexible tab 1812 may extend along at least a portion of the height of the outer sidewall of the annular core and be circumferentially aligned with the bottom beam 1724 of the clamp 1520. The proximal or apical end of the flexible tab 1812 is attached or secured to the top shoulder 1814 of the friction ring 1530, while the distal or bottom end of the flexible tab 1812 is not secured, thereby allowing the distal end of the flexible tab 1812 to bend or move relative to the secured proximal end. When the applicator 1500 is in a contracted configuration, the proximal end of the flexible tab 1812 is aligned with a portion of the inner diameter of the upper shoulder 1722 of the clamp 1520. During the transition from the contraction configuration to the extension configuration of the applicator 1500, the clamp 1520 moves axially relative to the friction ring 1530 along the length of the flexible tab 1812 toward and through the distal opening of the housing body. The flexible tab 1812 is bent or pushed inward until the clamp 1520 passes the distal end of the flexible tab 1812, at which point the flexible tab 1812 snaps onto the bottom beam 1724 and is held between a pair of guide walls 1726.

[0238] The friction ring 1530 may include more than one flexible tab 1812, which may be circumferentially distributed around the outer wall of the annular core in an equal or unequal manner. For example, as FIGS. 18A-18D As shown, three flexible tabs 1812 are evenly distributed around the outer wall of the annular core at 120-degree intervals. In some variations, four flexible tabs 1812 may be evenly distributed at 90-degree intervals, two flexible tabs 1812 may be evenly distributed at 180-degree intervals, or they may be directly opposite each other, and so on. The number of flexible tabs 1812 typically corresponds to the number of the bottom beam 1724 and the associated pair of guide walls 1726.

[0239] The friction ring 1530 may also include an outwardly extending surface for engaging and locking with the collar 1520. For example, the lower side 1728 of the upper shoulder 1722 of the collar 1520 may interface with the friction ring 1530 at the outwardly extending surface. The interface between the lower side 1728 of the collar 1520 and the outwardly extending surface of the friction ring 1530 can be used to maintain the axial position of the collar 1520 relative to the friction ring 1530. For example, the friction ring 1530 may include a protruding circumferential edge 1816. The protruding circumferential edge 1816 may project outwardly orthogonally to the height of the outer sidewall at the distal end or region of the outer sidewall of the annular core, such as... FIG. 18B As best shown. The protruding circumferential edge 1816 provides an interface or engagement point for the lower side 1728 of the sleeve 1520. When the sleeve 1520 moves axially downward relative to the friction ring 1530 during the transition of the applicator 1500 from a contraction configuration to an extension configuration, the lower side 1728 abuts against the protruding circumferential edge 1816, which prevents the sleeve 1520 from moving further downward axially.

[0240] The cushioning member 1818 may be positioned on the upper surface of the protruding circumferential edge 1816. The cushioning member 1818 may be an elastomer, a rubber strip, or the like, which cushions or softens the contact between the lower side 1728 of the clamp 1520 and the protruding circumferential edge 1816.

[0241] The friction ring 1530 may include more than one protruding circumferential edge 1816, which may be circumferentially distributed around the outer wall of the annular core in an equal or unequal manner. For example, as FIGS. 18A-18D As shown, three protruding circumferential edges 1816 are evenly distributed around the outer wall of the annular core at 120-degree intervals. In some variations, four protruding circumferential edges 1816 may be evenly distributed at 90-degree intervals, two protruding circumferential edges 1816 may be evenly distributed at 180-degree intervals or directly opposite each other, and so on.

[0242] The friction ring 1530 can include a coupling member that releasably couples to a ring retention surface of the housing 1510 to help lock the transfer member 1540 when the base 1550 is engaged with the housing 1510. For example, in some variations, in the collapsed configuration of the applicator 1500, the friction ring 1530 is retracted within the cuff 1520 and prevents firing of the transfer member 1540 until the base 1550 is removed.

[0243] For example, the housing 1510 can include at least one ring retention surface, the friction ring 1530 can be disposed within a cavity defined by the housing body, and include a protrusion 1820 that is removably coupled with the ring retention surface. In response to actuation of at least a portion of the housing 1510 toward the transfer member 1540 (e.g., the applicator can be placed in compression, for example, against a skin surface of a user), the ring retention surface of the housing can decouple from the protrusion 1820, which can result in release of the releasable coupling feature that couples the transfer member 1540 and the housing 1510.

[0244] As shown in FIG. 18C the protrusion 1820 can be disposed on an inner sidewall of the annular core and extend into the friction ring cavity 1810. The protrusion 1820 can include a surface, such as a planar surface that is orthogonal or substantially orthogonal to the inner sidewall of the annular core, that forms a releasable engagement with the ring retention surface of the housing 1510, as further described herein.

[0245] The friction ring 1530 can include more than one protrusion 1820, which can be distributed in an equal or unequal manner circumferentially around the inner sidewall of the annular core. For example, as shown in FIGS. 18A-18D three protrusions 1820 are evenly distributed around the inner sidewall of the annular core 120 at 120 degrees apart from each other. In some variations, four protrusions 1820 can be evenly distributed at 90 degrees apart from each other, two protrusions 1820 can be evenly distributed at 180 degrees apart from each other or directly opposite each other, and so on.

[0246] FIGS. 19A-19E Aspects of a cuff-ring assembly 1900 are depicted, including the cuff 1520 and the friction ring 1530 of the analyte monitoring device 1500. Shown in top perspective view, bottom view, top view, side view, side cross-sectional view, and two detailed views, respectively, FIGS. 19A-19E the cuff-ring assembly 1900 is in a locked state, in which the cuff 1520 and the friction ring 1530 are locked together.

[0247] The cuff 1520 and the friction ring 1530 can be locked or secured to one another by one or more engagement and locking features. When the applicator 1500 is in the collapsed configuration, the friction ring 1530 is retracted within the cuff 1520, and the engagement and locking features are not connected to one another. When the base 1550 is removed from the housing 1510, the applicator 1500 transitions from the collapsed configuration to the expanded configuration. During this transition, the cuff 1520 is moved or pushed downward, during which the engagement and locking features become engaged, thereby locking the cuff 1520 and the friction ring 1530 to one another.

[0248] As shown in FIGS. 19A and 19B, the cuff-ring assembly 1900 is shown in a locked state, in which the upper shoulder 1722 of the cuff 1520 is engaged with the friction ring 1530. FIG. 19A , 19D As shown in FIGS. 19A and 19B, the cuff-ring assembly 1900 is shown in a locked state, in which the upper shoulder 1722 of the cuff 1520 is engaged with the friction ring 1530.

[0249] FIG. 19E The detailed view provided in FIG. 19E is a close-up view showing a portion of the engagement and locking features of the cuff 1520 and the friction ring 1530 in the locked state.

[0250] As shown in the close-up view D, in the locked state, the underside 1728 of the upper shoulder 1722 of the cuff 1520 interfaces with the friction ring 1530 at the protruding circumferential edge 1816. This interface serves to maintain the axial position of the cuff 1520 relative to the friction ring 1530. For example, the protruding circumferential edge 1816 acts as a stop for the cuff 1520. As shown in the close-up view C, the flexible tab 1812 is snapped onto the lintel 1724 and is held in alignment between the pair of guide walls 1726.

[0251] FIGS. 20A-20F Aspects of the housing 1510 of the applicator 1500 for the analyte monitoring device 110 are depicted in accordance with some variations. The following aspects are provided, respectively: FIGS. 20A-20FFIG. 16A is a first top perspective view, FIG. 16B is a second top perspective view, FIG. 16C is a first bottom perspective view, FIG. 16D is a second bottom perspective view, FIG. 16E is a first side cross-sectional view, and FIG. 16F is a second side cross-sectional view of the applicator 1500 of FIG. 15. The housing 1510 is configured to be manipulated (e.g., manually by a user) to actuate the applicator 1500 in order to deploy the analyte monitoring device 110 releasably retained within the transfer piece 1540. The housing 1510 has a housing body 2002 that defines a cavity 2010 that receives the collar 1520, the friction ring 1530, and the transfer piece 1540. The housing body 2002 has a distal opening 2004. A first biasing element 1582 (e.g., a first compression spring) can be disposed within the cavity 2010 on or around a mount 2014 (e.g., a mounting or support structure) that extends downward from a proximal surface 2012 of the housing body 2002 through the cavity 2010. For example, the mount 2014 can extend from an underside of the proximal surface 2012 of the housing body 2002 such that the mount 2014 extends within the cavity 2010. The mount 2014 can be concentrically aligned or nested with the collar 1520, the friction ring 1530, and the transfer piece 1540. For example, the mount 2014 can extend through the locking friction ring cavity 1810 of the friction ring 1530, and the transfer piece shaft 1630 can extend through at least a portion of the mount 2014.

[0252] In some variations, as FIG. 20C FIG. 20F As shown, the mount 2014 includes a plurality of downwardly extending fingers 2016 arranged in a circumferential configuration. For example, the plurality of downwardly extending fingers 2016 are arranged such that the configuration defines a circular or substantially circular footprint. The circular or substantially circular footprint can correspond to an outer circumference of the transfer piece shaft 1630 such that the transfer piece shaft 1630 (e.g., an upper portion of the transfer piece shaft 1630) fits within the circular or substantially circular footprint. Variations in the shape and configuration of the footprint defined by the downwardly extending fingers 2016 can be based on the shape and configuration of the transfer piece shaft 1630 and / or the first biasing element 1582. Each downwardly extending finger 2016 can be configured to flex or bend outwardly along a portion of a length of the downwardly extending finger 2016 in response to a force.

[0253] One or more retention surfaces and / or features can be formed on the mount 2014. For example, each downwardly extending finger 2016 can have one or more retention members formed thereon. The retention surfaces and / or features can include a ring retention surface including a shoulder 2018 for releasably coupling with a protrusion 1820 of the friction ring 1530 to prevent firing of the transfer member 1540 until the base 1550 is removed. For example, the shoulder 2018 can be formed along an outwardly facing (e.g., first) surface of the downwardly extending finger 2016 and can couple with the shoulder 1820 by a distal surface of the protrusion 1820 contacting or resting on the shoulder 2018. In some variations, a ring retention slot (e.g., groove or channel) can be formed through or along the outwardly facing surface of the downwardly extending finger 2016, where the ring retention slot terminates at a distal end at the shoulder 2018. The ring retention slot can be sized such that the protrusion 1820 travels smoothly but firmly along its length. For example, a thickness of the protrusion 1820 can be close to a width of the ring retention slot. Upon actuation of the housing 1510, the housing 1510 moves downward relative to the collar 1520 and the friction ring 1530. During this downward movement of the housing 1510, the ring retention slot slides downward along the protrusion 1820 and the coupling (e.g., contact) between the shoulder 2018 and the protrusion 1820 is released.

[0254] The retention surfaces and / or features of each downwardly extending finger 2016 can also include a transfer member retention surface including a shoulder 2020 for releasably engaging a shelf 1634 of the transfer member 1540 to control axial movement of the transfer member 1540 upon release of the analyte monitoring device 110. For example, the shoulder 2020 can be formed along an inwardly facing (e.g., second) surface of the downwardly extending finger 2016 and the shoulder 2020 can engage a distal surface 1636 of the shelf 1634. The shelf 1634 and the distal surface 1636 can extend circumferentially along the transfer member shaft 1630. During actuation of the housing 1510, as the engagement between the shoulder 2018 and the protrusion 1820 is released, downward movement of the transfer member 1540 toward the distal opening 2004 of the housing body 2002 causes the shelf 1634 to push through (e.g., deflect or bend) the shoulder 2020, which is no longer inhibited by the friction ring 1530.

[0255] In some variations, each downwardly extending finger 2016 can include a shoulder 2018 formed along an outward facing surface of the downwardly extending finger 2016 and a shoulder 2020 formed along an opposite inward facing surface of the downwardly extending finger 2016. The number of downwardly extending fingers 2016 can correspond to the number of protrusions 1820. The downwardly extending fingers 2016 can be circumferentially distributed in an equal or unequal manner. For example, as shown in FIG. 19, the downwardly extending fingers 2016 can be circumferentially distributed in an equal manner. In other variations, the downwardly extending fingers 2016 can be circumferentially distributed in an unequal manner. For example, as shown in FIG. 20, the downwardly extending fingers 2016 can be circumferentially distributed in an unequal manner. FIG. 20DAs shown, three downwardly extending fingers 2016 are evenly distributed within the cavity 2010 at 120 degrees from each other. In some variations, four downwardly extending fingers 2016 can be evenly distributed at 90 degrees from each other, two downwardly extending fingers 2016 can be evenly distributed at 180 degrees from each other or directly opposite each other, etc.

[0256] In certain variations, the housing 1510 can include one or more guide members within the cavity 2010 along the interior sidewall of the housing body 2002. For example, one or more ribs can extend along the length or a portion of the length of the interior sidewall of the housing body 2002 and can interface with a corresponding outwardly facing member disposed along the length or a portion of the length of the cuff 1520. The guide members can assist in maintaining axial and rotational alignment of the cuff 1520 within the housing body 2002.

[0257] The housing 1510 can also include features that align with and retain the locking member 1560 in the configurable configuration. For example, a first side opening 2022 formed through the sidewall of the housing body 2002 can be sized and shaped to retain a depressible member of the locking member 1560 therein. A pivot surface 2024 can be formed at an elevation above the first side opening 2022 and can provide a pivot surface for the locking member 1560. For example, the pivot surface 2024 can provide a point along which the locking member 1560 can pivot to release the locking member 1560 from its engagement with the cuff 1520. At an elevation above the pivot surface 2024, a second side opening 2026 can be formed through the sidewall of the housing body 2002. The second side opening 2026 can be sized and shaped to retain a pivot member of the locking member 1560 therein. A flexible contact member 2028 can be formed at an elevation above the second side opening 2026. The flexible contact member 2028 can be fixed at its proximal end to the sidewall of the housing body 2002. The distal end of the flexible contact member 2028 can be unfixed relative to the sidewall of the housing body 2002 and can be configured to flex outwardly from the sidewall in response to an applied force. For example, the distal end of the flexible contact member 2028 can engage a portion of the pivot member of the locking member 1560. When the pivot member is pivoted outwardly along the pivot shaft 2024, the flexible contact member 2028 flexes outwardly in response to the pivoting motion but limits the outward pivoting or flexing motion of the locking member 1560.

[0258] In certain variations, the housing 1510 can include features for connecting / interfacing with and / or securing the base 1550. For example, one or more grooves or slots can be formed in one or more portions of the distal end of the housing body 2002 to receive a portion of the base sidewall of the base 1550, and / or one or more grooves or slots can be formed in the interior sidewall of the housing body 2002 to receive a corresponding one or more arms of the base 1550, as further described herein.

[0259] In some variations, the housing 1510 can include or be coupled to an outer enclosure 1570. For example, the outer enclosure 1570 can be a grip that can include a sheath or ring that slides around the housing 1510 or is coupled to the housing 1510 by a suitable mechanical fit (e.g., threads, interference fit, etc.). In some variations, the outer enclosure 1570 can be integrally formed with (e.g., overmolded with) the housing 1510 and / or the housing 1510 can include one or more gripping features. In some variations, the outer enclosure 1570 can include one or more features for enhancing the ability of a user to manipulate the housing 1510. For example, the outer enclosure 1570 can include one or more recessed or otherwise indented contours having finger-receiving surfaces to improve manual gripability. Additionally or alternatively, the outer enclosure 1570 can include one or more raised textured features (bumps, ridges, ribs, rings, etc.) to increase friction. Additionally or alternatively, the outer enclosure 1570 can incorporate one or more materials having greater friction (e.g., silicone / silicones or other elastomers). In some variations, the outer enclosure 1570 is an elastomeric material that provides an environmental enclosure for the housing body 2002 and components disposed therein (e.g., by substantially surrounding the housing body 2002). The outer enclosure 1570 can also control acoustics (e.g., reduce sound generated by actuation of the applicator) and vibration (e.g., dampen vibration between the user and applicator components generated by actuation of the applicator).

[0260] FIGS. 21A-21BA number of aspects of a locking member 1560 of an applicator 1500 for an analyte monitoring device 110 are depicted in front and rear perspective views, respectively. The movable locking member 1560 fits within a corresponding feature of the housing body 2002 and is aligned with and at least partially fits within a retaining wall 1712 formed on an outer sidewall of the cuff 1520. For example, the outer perimeter of the locking member 1560 at the rear surface can be an elongated member that fits within the retaining wall 1712 defined by the retaining lip 1714. The locking member 1560 includes a depressible member 2110, a pivot rod 2112, and a pivoting member 2114 having a flat or substantially flat upper edge 2116. The depressible member 2110 can be in the form of a button or nub and can have a configuration for fitting within and extending through a first side opening 2022 of the housing 1510. The depressible member 2110 is generally sized and shaped to allow a user to access and depress the depressible member 2110. The pivot rod 2112 is a rod-like member that extends through a second side opening 2026 of the housing 1510 and along a pivot surface 2024. For example, the pivot rod 2112 is movably engaged with the pivot surface 2024 such that when the depressible member 2110 is depressed inward (e.g., pressed), the locking member 1560 pivots at the interface between the pivot rod 2112 and the pivot surface 2024. Pivoting movement of the locking member 1560 causes the pivoting member 2114 to move outward. That is, when the depressible member 2110 is depressed or pushed inward in the first opening 2022, the pivoting member 2114 moves outward from the second side opening 2026. The outward movement of the pivoting member 2114 is controlled or limited by a flexible contact member 2028 of the housing 1510.

[0261] The pivoting member 2114 has a flat or substantially flat upper edge 2116 that releasably engages with a top edge of the retaining lip 1714 that defines the retaining wall 1712 of the cuff 1520. In the collapsed configuration of the applicator 1500, the locking member 1560 is positioned within the retaining wall 1712 such that the upper edge 2116 of the movable locking member 1560 engages under the top edge of the retaining lip 1714, thereby preventing downward movement of the cuff 1520 relative to the housing body 2002. When the locking member 1560 is depressed, the vertical movement of the cuff 1520 is no longer impeded due to the outward movement of the pivoting member 2114 away from the top edge of the retaining lip 1714.

[0262] Accordingly, the locking member 1560 is engaged with the cuff 1520 in a first configuration and disengaged from the cuff 1520 in a second configuration. In some variations, movement of the locking member 1560 from the first configuration to the second configuration releases the cuff 1520, thereby decoupling the proximal surface of the base 1550 from the housing body 2002, as further described herein.

[0263] In some variations, one locking member 1560 is provided. In some variations, two locking members 1560 are provided. The combination of two locking members 1560 provides the applicator 1500 with a locking system that requires an intentional and controlled user action (e.g., pressing both locking members 1560 simultaneously or nearly simultaneously) to unlock the applicator 1500 and transition the applicator 1500 from the retracted configuration to the extended configuration to deploy the analyte monitoring device 110.

[0264] FIGS. 22A-22G Aspects of a base 1550 of an applicator 1500 for an analyte monitoring device 110 according to some variations are depicted. In FIGS. 22A-22G the base 1550 is shown in a top perspective view, a top view, a bottom view, a first side view, a first side cutaway view, a second side view, and a second side cutaway view, respectively. Generally, the base 1550 provides an enclosed area for the analyte monitoring device 110 prior to a user preparing to apply the analyte monitoring device 110. The base 1550 is removably coupled to the housing body 2002 at the distal opening 2004. The base 1550 is held in place by releasable engagement between features of the base 1550, the cuff 1520, and the housing body 2002, as further described herein. When the locking member 1560 is moved from the first configuration to the second configuration, the base 1550 is disengaged from its releasable engagement with the cuff 1520 and the housing body 2002, and subsequently a removal force is applied to the base 1550 by the user. The release of the locking member 1560 from engagement with the top edge of the retention lip 1714 of the cuff 1520 allows the cuff 1520 to translate vertically toward the distal opening 2004 of the housing body 2002. Movement of the cuff 1520 toward the distal opening 2004 contacts and pushes the base 1550 in the same direction.

[0265] As the clamp 1520 advances downward, the conveyor 1540 moves to a position where the shoulder 2020 of the one or more downwardly extending fingers 2016 engages with a shelf 1634 formed on the conveyor shaft 1630 (e.g., at the distal surface 1636). The clamp 1520 travels further downward until it is stopped by the protruding circumferential edge 1816 of the friction ring 1530, and the friction ring 1530 is locked into the clamp 1520 by engaging the bottom beam 1724 with a flexible tab 1812. Further movement of the conveyor 1540 is prevented by the shoulder 2020 of the one or more downwardly extending fingers 2016 as the clamp 1520 moves axially downward. Simultaneously, further downward movement causes the base 1550 to be pushed further downward, preventing the base 1550 from being reattached by its locking arm, and placing the base 1550 in a position where it can be released by the user applying a removal force. After the user applies a removal force to the base 1550, the applicator 1500 is in an extended configuration, wherein the components of the applicator 1500 are aligned with the analyte monitoring device 110 and ready to apply the analyte monitoring device 110 when the housing 1510 is actuated.

[0266] In some variations, such as FIGS. 22A-22G As shown, the base 1550 has a proximal surface 2210, and a base sidewall 2212 extends upward from a portion of the proximal surface 2210. The proximal surface 2210 may have a generally flat surface with curved edges that abut against the bottom edges of the housing body 2002 and / or the outer cover 1570 to form a sealed cover between them. In some variations, the base sidewalls 2212 may extend continuously in a circular or generally circular arrangement. In some variations, the base sidewalls 2212 may be individual and discrete components that together form a circular or generally circular coverage area. The upper edge of the base sidewall 2212 may fit into a corresponding groove formed in the bottom edge of the housing body 2002 such that when the applicator 1500 is in a contracted configuration, the base sidewall 2212 is surrounded by the housing body 2002.

[0267] The base 1550 can be configured to form a secure attachment with the microneedle capsule 500 connected to the analyte monitoring device 110. For example, an interior portion of the base 1550 can be sized and shaped such that the clamp 520 (of the microneedle capsule 500) can fit and / or be contained within the interior portion. In some variations, the base 1550 includes a receiving area or compartment that provides an encompassing capsule for the microneedle capsule 500. When the microneedle capsule 500 and the base plate 330 of the analyte monitoring device 110 are attached to one another by the locking tab 528 and the connection member 332, the microneedle capsule 500 and the base plate 330 can be contained within the receiving area of the base 1550. As described further herein, an engagement can be made between the exterior engagement feature 526 of the microneedle capsule 500 and a clamp engagement feature formed within the receiving area of the base 1550.

[0268] FIG. 22H FIG. 22J Aspects of the base 1550 and the microneedle capsule 500 are depicted in exploded view, top perspective view, and side cross-sectional view, respectively, as described herein.

[0269] In some variations, the receiving area can include a capsule sidewall 2214 extending upwardly from a central region of the proximal surface 2210 within an interior of the base sidewall 2212. The capsule sidewall 2214 can form a perimeter that surrounds or interfaces with an outer periphery of the base plate 330 of the analyte monitoring device 110. Within the capsule sidewall 2214, the clamp engagement feature can include a plurality of upwardly extending flexible fingers 2216 each having a chamfered or beveled edge and a plurality of walls 2217 each engaging the exterior engagement feature 526 of the clamp 520. The upwardly extending flexible fingers 2216 flex outwardly to receive the microneedle capsule 500, the chamfered or beveled edges secure the microneedle capsule 500, and the walls 2217 limit rotational movement of the microneedle capsule 500. The flexible fingers 2216 can be arranged in an alternating pattern with the walls 2217, and the flexible fingers 2216 and the walls 2217 can be positioned circumferentially around an inner perimeter of the capsule sidewall 2214 such that the flexible fingers 2216 and the walls 2217 form a footprint for the clamp 520.

[0270] For example, the exterior engagement feature 526 of the clamp 520 can include an extension surface that orthogonally projects from a middle region of the clamp 520 and terminates at a fin-like portion that extends from the extension surface in an orthogonal direction to a proximal end or proximal end vicinity of the clamp 520, as FIG. 5E and 5FThe outer engagement features 526 of the clip 520 can be positioned circumferentially around the outer edge of the clip 520, and each outer engagement feature 526 (including the extension surface and the fin) can correspond to a respective flexible finger 2216 and wall 2217 of the base 1550. The extension surface of the clip 520 can interface with the flexible finger 2216 such that upon the application of pressure therebetween, the extension surface is secured beneath the upper edge of the flexible finger 2216 (e.g., the flexible finger 2216 flexes outward under pressure to allow the extension surface to snap fit beneath the chamfered or beveled upper edge of the flexible finger 2216).

[0271] The rotational motion of the clip 520 is limited or constrained due to the interface between the fin of the clip 520 and the wall 2217. For example, the rotational motion of the clip 520 stops when the fin of the clip 520 contacts the wall 2217 of the base 1550. Because the clip 520 has a rotatable connection to the connection member 332 of the substrate 330 (as described above with reference to FIGS. 1-5G), the rotation of the clip 520 while retained within the clip engagement features of the base 1550 can cause the clip 520 and the substrate 330 to disengage. For example, by rotating the clip 520 such that the locking tab 528 of the clip disengages from the connector feature 336 of the substrate 330, the microneedle enclosure 500 (retained within the base 1550 by the clip engagement features (e.g., the engagement of the flexible finger 2216 and the extension surface of the clip 520)) can be lifted off of the substrate 330. FIG. 5E 、 5F Because the clip 520 has a rotatable connection to the connection member 332 of the substrate 330 (as described above with reference to FIGS. 1-5G), the rotation of the clip 520 while retained within the clip engagement features of the base 1550 can cause the clip 520 and the substrate 330 to disengage. For example, by rotating the clip 520 such that the locking tab 528 of the clip disengages from the connector feature 336 of the substrate 330, the microneedle enclosure 500 (retained within the base 1550 by the clip engagement features (e.g., the engagement of the flexible finger 2216 and the extension surface of the clip 520)) can be lifted off of the substrate 330.

[0272] Accordingly, when the analyte monitoring device 110 with the microneedle enclosure 500 is installed within the base 1550, the microneedle array 140 of the analyte monitoring device 110 is contained within the sterile environment provided by the sheath 510 until the compressive engagement between the clip 520 and the substrate 330 is disengaged. In some variations, once the microneedle enclosure 500 is attached to the base 1550 and the base 1550 is attached to the housing 1510, the rotational locking arrangement between the microneedle enclosure 500 and the substrate 330 can be disengaged by, for example, a manufacturing operation that maintains the engagement between the flexible finger 2216 and the microneedle enclosure 500. Then, due to the compression from the biasing elements 530, 1582, and 1584, the microneedle array 140 remains in its sterile environment until the base 1550 is disengaged from the housing 1510. Disengagement of the base 1550 causes the microneedle enclosure 500 to be removed with the base 1550 because the microneedle enclosure 500 is rotationally disengaged from the substrate 330 (by the preceding manufacturing disengagement operation) and secured in the base 1550 by the snap attachment with the flexible finger 2216.

[0273] In some variations, the base 1550 includes arms that facilitate engagement and release between the base 1550, the ferrule 1520, and the housing body 2002. The base 1550 can include locking arms 2218 that extend from the proximal surface 2210 in an upwardly projecting configuration. The locking arms 2218 can be configured to flex or snap into locking retention grooves formed in the sidewall of the housing body 2002 when the base 1550 is connected to the housing body 2002. For example, during assembly of the applicator 1500, the locking arms 2218 can be flexed inwardly to allow outwardly projecting surfaces of the locking arms 2218 to be positioned in (e.g., snapped into) the locking retention grooves and biased radially outwardly. During release of the base 1550 as the base 1550 is pushed downwardly, the locking arms 2218 disengage (e.g., are pulled out of) the locking retention grooves and are pushed past a wall surface formed in the sidewall of the housing body 2002 in the axial downward movement of the base 1550. Once the locking arms 2218 move past the wall surface, the user is prevented from reattaching the base 1550 to the housing body 2002 as the wall surface prevents axial upward movement of the locking arms 2218.

[0274] In some variations, the base 1550 can include more than one locking arm 2218 that can be distributed and / or positioned circumferentially around the proximal surface 2210 in an equal or unequal manner. For example, as shown, the base 1550 includes four locking arms 2218 distributed around the proximal surface 2210. FIG. 22A

[0275] In some variations, the locking arms 2218 can be flexed outwardly to allow outwardly projecting surfaces of the locking arms 2218 to be positioned in (e.g., snapped into) the locking retention grooves and biased radially inwardly.

[0276] ​The base 1550 includes retaining arms that releasably engage with the base retaining surface of the collar 1520. When the applicator 1500 is in the collapsed configuration, the retaining arms are prevented from disengaging from their engagement with the collar 1520 and the housing body 2002 by the configuration / configuration of the base retaining surface of the collar 1520 and the housing body 2002. For example, the base 1550 can include retaining arms 2220 that extend from the proximal surface 2210 in an upwardly projecting configuration. When the applicator 1500 is in the collapsed configuration, the retaining arms 2220 can be sandwiched between the outer lateral surface of the collar 1520 and the inner lateral surface of the housing body 2002. The inwardly projecting surface of the retaining arms 2220 can engage with the base retaining surface 1730 of the collar 1520. This engagement or locking configuration prevents disengagement between the base 1550 and the housing body 2002. In releasing the base 1550, the base 1550 is pushed downwardly with the collar 1520 and the engagement between the retaining arms 2220 and the base retaining surface 1730 is maintained. Upon the point of engagement passing beyond the housing body 2002, the base 1550 is in a configuration in which it can be removed by a removal force applied by a user.

[0277] In some variations, the base 1550 can include more than one retaining arm 2220, and the releasable retaining arms 2220 can be distributed circumferentially around the proximal surface 2210 in an equal or unequal manner. For example, as shown, the base 1550 includes four releasable retaining arms 2220 distributed around the proximal surface 2210. FIG. 22A

[0278] In some variations, the length of the locking arms 2218 is greater than the length of the retaining arms 2220. In some variations, the length of the retaining arms 2220 is greater than the length of the locking arms 2218. In some variations, the length of the locking arms 2218 is equal to or approximately equal to the length of the retaining arms 2220.

[0279] FIG. 22K Aspects of the applicator base 1550 in engagement with the collar 1520 are shown in a top perspective view. As shown, the collar 1520 includes a bottom flange 1732 having an increased surface area and a cutout 1734 formed through the bottom flange for accommodating the arms of the base 1550 (e.g., the locking arms 2218 and the retaining arms 2220).

[0280] FIGS. 23A-23O Views of the applicator 1500 in an assembled form according to the variations described herein are shown in a cross-sectional view and close-up view. FIGS. 23A-23F The applicator 1500 is shown in a collapsed configuration. FIGS. 23G-23K ​The applicator 1500 is shown in the process of being released from engagement with the housing body 2002 to transition the applicator 1500 from the collapsed configuration to the extended configuration. FIGS. 23L-23O The movement of the applicator 1500 from the extended configuration, in which the analyte monitoring device 110 is ready to be released, to the released configuration, in which the analyte monitoring device 110 is released from the applicator 1500, is shown sequentially. FIGS. 23A-23O The analyte monitoring device 110 is shown in some views. In cases where the details of the analyte monitoring device 110 are not essential to the particular aspect shown, the analyte monitoring device 110 can be omitted from the view. The microneedle enclosure 500 is shown in some views, but is omitted in other views where the details of the microneedle enclosure 500 are not essential to the particular aspect shown. FIGS. 23A-23O The analyte monitoring device 110 is shown in some views. In cases where the details of the analyte monitoring device 110 are not essential to the particular aspect shown, the analyte monitoring device 110 can be omitted from the view. The microneedle enclosure 500 is shown in some views, but is omitted in other views where the details of the microneedle enclosure 500 are not essential to the particular aspect shown.

[0281] Referring to FIGS. 23A-23F The applicator 1500 is depicted in the collapsed configuration, in which the components are locked (e.g., fixed) relative to one another, and the analyte monitoring device 110 cannot be deployed.

[0282] In the collapsed configuration, the friction ring 1530 is retracted within the collar 1520, and the locking member 1560 is engaged with the collar 1520. The second biasing element 1584 is positioned in the inner cavity 1632 defined by the transfer shaft 1630 and is compressed to the first compressed state of the second biasing element 1584. The first biasing element 1582 is positioned within the cavity 2010 defined by the housing body 2002 and is compressed to the first compressed state of the first biasing element 1582. The shelf 1634 (e.g., the distal surface 1636) of the transfer shaft 1630 is positioned proximal to (e.g., with a gap therebetween) the shoulder 2020 of the downwardly extending finger 2016. The analyte monitoring device 110 is retained by the transfer 1540.

[0283] In the collapsed configuration of the applicator 1500, the locking tab 528 of the microneedle enclosure and the connector feature 336 of the substrate 330 are disengaged. The sterile seal provided by the microneedle enclosure 500 is maintained by the counterforce of the microneedle enclosure biasing element 530 and the counterforce of the first and second biasing elements 1582, 1584. Further, while the analyte monitoring device 110 is retained between these counterforces, the analyte monitoring device 110 is able to move relative to the components of the applicator 1500. This movement allows the bumper 512 (e.g., the seal around the casing 510) to reliably remain in contact with the analyte monitoring device, thereby maintaining sterility in the presence of vibration, temperature changes, and other environmental conditions.

[0284] As FIG. 23AAs shown, the microneedle enclosure 500 is contained within the base 1550 and connected to the analyte monitoring device 110. The external engagement feature 526 of the microneedle enclosure 500 is secured beneath the chamfer or bevel of the flexible finger 2216 formed in the base 1550, allowing the microneedle enclosure 500 to be removed when the base 1550 is released from the housing body 2002. As FIG. 23A As shown, in the retracted configuration, the distal edge of the transfer member 1540 and the cuff 1520 are in the proximal most position and are located proximal to the distal opening 2004 of the housing body 2002. In some variations of the retracted configuration, the distal edge of the cuff 1520 and the transfer member 1540 are located proximal to the distal opening 2004 of the housing body 2002.

[0285] Referring to FIG. 23B , a detailed view of the locking member 1560 is provided, which is mounted within the retaining wall 1712 formed on the outer sidewall of the cuff 1520. The close-up view depicts the upper edge 2116 of the locking member 1560 engaged beneath the top edge of the retaining lip 1714 of the retaining wall 1712. This engagement between the locking member 1560 and the cuff 1520 prevents the cuff 1520 from moving downward relative to the housing body 2002. When the applicator 1500 is in the retracted configuration, the engagement and locking features of the cuff 1520 and the friction ring 1530 are not connected to one another because the friction ring 1530 is retracted within the cuff 1520.

[0286] As FIG. 23C and 23D shown, the friction ring 1530 within the cuff 1520 is configured to prevent the transfer member 1540 from being triggered / fired in the retracted configuration. This is because when the friction ring 1530 is retracted within the cuff 1520 and sandwiched between the cuff 1520 and the mount 2014 of the housing 1510, the friction ring 1530 prevents the transfer member 1540 from being vertically displaced toward the distal opening 2004; due to the position of the friction ring 1530, the downwardly extending finger 2016 of the mount is not able to flex a sufficient amount to allow the vertical displacement of the transfer member 1540. In other words, when the applicator 1500 is in the retracted configuration, the transfer member 1540 is locked in place due to the concentric arrangement of the mount 2014, the friction ring 1530, and the cuff 1520.

[0287] FIG. 23E and 23FAspects of the base 1550 in engagement with the housing body 2002 and the collar 1520 when the applicator 1500 is in the retracted configuration are depicted. The upper edge of the base sidewall 2212 fits into a corresponding groove formed in the distal edge of the housing body 2002 such that the base sidewall 2212 is enclosed by the housing body 2002. The locking arms 2218 of the base 1550 fit into locking retention grooves formed in the sidewalls of the housing body 2002 as shown in the close-up view of FIG. 23E As shown in the close-up view of FIG. 23F The retention arms 2220 of the base 1550 are sandwiched between the outside surface of the collar 1520 and the inside surface of the housing body 2002 as shown in the close-up view of

[0288] Referring to FIGS. 23G-23K Aspects related to the release of the base 1550 from engagement with the housing body 2002, transitioning the applicator 1500 from the retracted configuration to the extended configuration are shown. Upon pressing the locking members 1560 (e.g., when the pressable members 2110 are pressed inwardly to move from the first configuration to the second configuration), each locking member 1560 pivots at the interface between the pivot rod 2112 of the locking member 1560 and the pivot surface 2024 of the housing body 2002. The pivoting motion causes the pivot member 2114 of the locking member 1560 to move outwardly in the second side opening 2026 and the upper edge 2116 of the pivot member 2114 is no longer locked under the top edge of the retention lip 1714 of the collar 1520. Thus, upon pressing the locking members 1560, the vertical movement of the collar 1520 is no longer impeded due to the outward movement of the pivot member 2114 away from the top edge of the retention lip 1714. In the extended configuration of the applicator 1500, the distal edge of the collar 1520 is in the distal-most position and the delivery member 1540 is in the intermediate position. In some variations of the extended configuration, the distal edge of the collar 1520 is distal to the distal opening 2004 of the housing body 2002 and the delivery member 1540 is proximal to the distal opening 2004 of the housing body 2002. In some variations of the extended configuration, the distal edge of the collar 1520 is distal to the distal opening 2004 of the housing body 2002 and the delivery member 1540 is proximal to the distal opening 2004 of the housing body 2002.

[0289] FIG. 23G The disengagement between the collar 1520 and the locking members 1560 is shown. The release of the locking members 1560 from engagement with the top edge of the retention lip 1714 of the collar 1520 allows the collar 1520 to move vertically in the downward direction as shown in the close-up view of FIG. 23GThe downward movement of the ferrule 1520 pushes the base 1550 in the same downward direction (e.g., at the proximal surface 2210). FIG. 23G The close-up view in FIG. 27 depicts the release of the locking member 1560 from engagement with the top edge of the retention lip 1714 of the ferrule 1520, and the outward movement of the pivoting member 2114 is limited by the flexible contact member 2028 of the housing body 2002.

[0290] FIG. 23H The close-up view in FIG. 27 depicts the release of the locking member 1560 from engagement with the top edge of the retention lip 1714 of the ferrule 1520, and the outward movement of the pivoting member 2114 is limited by the flexible contact member 2028 of the housing body 2002. FIG. 23H The protruding circumferential edge 1816 of the friction ring 1530 blocks further downward advancement of the ferrule 1520, which provides an interface or point of engagement for the underside 1728 of the ferrule 1520. The engagement between the ferrule 1520 and the friction ring 1530 prevents the ferrule 1520 from moving distally relative to the distal opening 2004 of the housing body 2002.

[0291] FIG. 23I The close-up view in FIG. 27 depicts the release of the locking member 1560 from engagement with the top edge of the retention lip 1714 of the ferrule 1520, and the outward movement of the pivoting member 2114 is limited by the flexible contact member 2028 of the housing body 2002. FIG. 23I The close-up view in FIG. 27 depicts the release of the locking member 1560 from engagement with the top edge of the retention lip 1714 of the ferrule 1520, and the outward movement of the pivoting member 2114 is limited by the flexible contact member 2028 of the housing body 2002.

[0292] FIG. 23J and 23KAspects of the arms of the base 1550 are depicted as the base 1550 is pushed downward during the transition of the applicator 1500 to the extended configuration. FIG. 23J The lock arm 2218 is shown disengaged from the lock retaining groove of the housing body 2002. As shown in the close-up view of FIG. 23J When the lock arm 2218 is pushed beyond the lock retaining groove, the user is prevented from reattaching the base 1550 onto the housing body 2002 as the wall surface below the lock retaining groove blocks the upward axial movement of the lock arm 2218, as shown in the close-up view of FIG. 23K The engagement between the retaining arm 2220 and the base retaining surface 1730 is shown as the base 1550 is pushed downward with the cuff 1520. At the point of engagement beyond the housing body 2002, the base 1550 is in a configuration in which it can be removed by a removal force applied by a user. For example, a user can grasp the base 1550 and pull the base 1550 down, the pulling force overcoming the engagement between the retaining arm 2220 and the base retaining surface 1730.

[0293] Referring to FIGS. 23L-23O , aspects related to the applicator 1500 moving from the extended configuration to the release configuration are shown. In the extended configuration, the components of the applicator 1500 are arranged and configured such that the analyte monitoring device 110 is deployable (e.g., released) from the applicator 1500 in response to actuation of the housing 1510. The base 1550 is removed, and the transfer 1540 is moved to a cocked position in the extended configuration. In the release configuration, the analyte monitoring device 110 is released from the applicator 1500 and inserted into the skin of a user.

[0294] During actuation of the housing 1510, the friction ring 1530 and the cuff 1520 act as a single component and function to disengage the analyte monitoring device 110 from the transfer 1540. The transfer 1540 is axially aligned and nested within the friction ring 1530. FIG. 23L Details of the transfer 1540 positioned in the extended configuration are depicted. In the extended configuration, the mount 2014 is releasably engaged with the friction ring 1530, and the mount 2014 is releasably engaged with the transfer 1540. In this configuration, the transfer 1540 is moved to a position in which the shoulder 2020 of the downwardly extending finger 2016 is engaged with the shelf 1634 of the transfer shaft 1630, and the shoulder 2018 of the downwardly extending finger 2016 is engaged with the protrusion 1820 of the friction ring 1530, as shown in the close-up view of FIG. 23L .

[0295] FIG. 23M , FIG. 23N and FIG. 23O Details of the applicator 1500 in the release configuration are shown in first, second, and third cross-sectional views, respectively. In particular,FIG. 23M 、 23N and 23O depict the arrangement of applicator components when the applicator 1500 is in the release configuration with the analyte monitoring device 110 deployed from the delivery member 1540. As shown in FIG. 23M 、 23N and 23O, the second biasing element 1584 is compressed less because the energy stored in the second biasing element 1584 when loaded has been transferred to the delivery member 1540 to drive the analyte monitoring device 110 with the appropriate application force. In the release configuration, the analyte monitoring device 110 is released from the delivery member 1540. In the release configuration, the distal edge of the cuff 1520 is in the intermediate position and the delivery member 1540 is in the distal-most position. In some variations of the release configuration, the distal edges of both the cuff 1520 and the delivery member 1540 are distal of the distal opening 2004 of the housing body 2002. In some variations of the release configuration, the distal edge of the cuff 1520 is distal of the distal opening 2004 of the housing body 2002 and the delivery member 1540 is distal of the distal opening 2004 of the housing body 2002.

[0296] FIG. 23M depicts the disengagement detail between the friction ring 1530 and the housing body 2002. More specifically, as shown in the close-up view of FIG. 23N When the housing body 2002 is actuated (e.g., pushed down), the protrusion 1820 of the friction ring 1530 disengages from the shoulder 2018 of the housing 1510. As the downward movement causes the friction ring 1530 to disengage from the downwardly extending finger 2016 on which the shoulder 2018 is formed, the releasable coupling feature between the delivery member 1540 and the downwardly extending finger 2016 releases. More specifically, the downward movement of the delivery member 1540 causes the shelf 1634 to push past the shoulder 2020 (e.g., the downwardly extending finger 2016 flexes away from the delivery member 1540). This flexing or deflection is possible because the downwardly extending finger 2016 is no longer inhibited or blocked by the protrusion 1820. Additionally, during actuation of the housing body 2002, as the housing body 2002 moves downward relative to the cuff 1520 and the friction ring 1530, the ring-retaining slot formed in the outward-facing sidewall of the downwardly extending finger 2016 slides along the protrusion 1820 in the distal direction.

[0297] FIG. 23O and FIG. 23ODetails of the tracks 1716 formed along the collar 1520 through which one or more tracking protrusions 1616 on the delivery member 1540 travel during actuation of the housing body 2002 are depicted. Each track 1716 ends at a distal end with a delivery member flex surface 1718, where the delivery member flex surface 1718 acts as a stop for axial movement of the delivery member 1540 to help the flexible leaflets 1612 of the delivery member 1540 bend radially outward, as FIG. 24 shown in the close-up view. As the flexible leaflets 1612 bend radially outward, the analyte monitoring device 110 is released from the delivery member 1540. The second biasing element 1584 provides an external pressure for the radial outward bending as the second biasing element 1584 is compressed in the inner lumen 1632 of the delivery member 1540. The delivery member flex surface 1718 of the collar 1520 blocks axial movement of the delivery member 1540, and the energy stored in the second biasing element 1584 is transferred to the delivery member 1540, causing the flexible leaflets 1612 to bend radially outward to push the analyte monitoring device 110 out with a suitable force (e.g., for suitable insertion of the microneedle array 140 into the skin of a user). As the microneedle array 140 is inserted into the skin of a user, an adhesive layer (e.g., the outer adhesive layer 344) adheres the analyte monitoring device 110 to the skin of the user. The analyte monitoring device 110 can be removed by applying enough force to overcome the adhesive layer.

[0298] FIG. 24 A process flow diagram P2400 is shown, including a process of moving the applicator 1500 from a retracted configuration to an extended configuration to move the analyte monitoring device 110 to a ready-to-release position. The process proceeds sequentially along the left side of the process flow diagram from S2410 to S2420 to S2430 to S2440 and to S2450. Aspects connected by dashed lines and dashed boxes depict different states and configurations of the applicator components after each process step. The order in which the different states and configurations appear can vary, and is not limited to FIG. 25 the order shown.

[0299] At S2410, the locking member 1560 is pressed (e.g., moved from a first configuration to a second configuration). The pressing of the locking member 1560 includes the locking member 1560 disengaging from the collar 1520.

[0300] At S2420, the cuff 1520 is axially displaced towards the distal end 2004 of the housing body 2002. This axial displacement of the cuff 1520 results in an engagement between the cuff 1520 and the friction ring 1530. In particular, the flexible tabs of the friction ring 1530 snap over the bottom beams of the cuff 1520 and the protruding edges of the friction ring 1530 engage the underside of the proximal end of the cuff 1520. Further, the first biasing element 1582 moves from its first compressed state to a second compressed state of the first biasing element which is less than the first compressed state.

[0301] At S2430, the base 1550 is axially displaced as the cuff 1520 pushes against the proximal surface 2210 of the base. The axial displacement of the base 1550 results in the sterile seal provided by the microneedle enclosure 500 being broken. The axial displacement of the base 1550 further results in the locking arms of the base 1550 disengaging from the locking groove of the housing body 2002.

[0302] At S2440, the delivery member 1540 falls into the fired position. In the fired position, the delivery member 1540 is configured to fire or advance the analyte monitoring device 110 for insertion of the analyte monitoring device 110 into the skin of a user. When the delivery member 1540 falls into the fired position, the shoulder 2020 of the downwardly extending finger engages the shelf 1634 of the delivery member shaft. The second biasing element 1584 moves from its first compressed state to a second compressed state of the second biasing element which is slightly less than its first compressed state due to the axial movement of the delivery member 1540 into the fired position.

[0303] At S2450, the base 1550 is pulled down. The user can pull down the base 1550 by exerting an appropriate force. At this point, the applicator 1500 is in the extended configuration.

[0304] FIG. 25 A process flow diagram P2500 is shown, comprising a process of moving the applicator 1500 from the extended configuration to the released configuration for insertion of the analyte monitoring device. The process proceeds sequentially along the left side of the process flow diagram from S2510 to S2520 to S2530 and S2540. The different states and configurations of the applicator components following each process step are depicted by the aspects connected by dashed lines and dashed boxes. The order in which the different states and configurations appear can vary and is not limited to FIG. 26A the order shown.

[0305] At S2510, the applicator 1500 in the extended configuration is placed on the user. The distal end of the cuff 1520 is in contact with the human skin at the insertion site where the applicator 1500 is placed.

[0306] At S2520, the housing body 2002 is actuated (e.g., pushed down for axial displacement). This actuation causes a gap or separation between the protrusion 1820 of the friction ring 1530 and the shoulder 2018 formed on the downward extending finger 2016. The axial displacement of the downward extending finger 2016 causes the separation due to the connection within the cavity 2010 of the housing body 2002. The shelf 1634 of the transfer member shaft pushes past the shoulder 2020 of the downward extending finger. This actuation further causes the first biasing element 1582 to move to a third compressed state of the first biasing element that is greater than its second compressed state. In addition to the movement and / or changes to the applicator components upon actuation, the actuation also causes the human skin within the area defined by the distal edge of the cuff 1520 to bulge.

[0307] At S2530, the transfer member 1540 is axially displaced towards the distal opening 2004 of the housing body 2002. The second biasing element 1584 moves to a third compressed state of the second biasing element that is less than its second compressed state. The axial displacement of the transfer member 1540 causes the microneedle array 140 to contact and be inserted into the human skin at the insertion site. Continued axial displacement of the transfer member 1540 causes the adhesive to adhere to the human skin at the insertion site.

[0308] At S2540, the tracking protrusion on the transfer member 1540 engages with the transfer member curved surface of the cuff 1520. The engagement between the tracking protrusion and the transfer member curved surface causes the flexible blades of the transfer member 1540 to splay or flex radially outward, thereby releasing the analyte monitoring device.

[0309] FIG. 26B and FIG. 26A Multiple aspects of the transfer member locking mechanism are shown in cross-sectional and close-up views. As shown, the shelf 1634 formed on the transfer member shaft 1630 includes a distal surface 1636 and a proximal surface 1638. In some variations, the proximal surface 1638 of the shelf 1634 can be used as a transfer member locking feature. FIG. 26B The applicator 1500 is shown in an extended configuration with the distal surface 1636 of the shelf 1634 of the transfer member shaft 1630 engaged with the shoulder 2020 of the downward extending finger 2016 to control the movement of the transfer member 1540 towards the distal opening 2004 of the housing body 2002.

[0310] FIGS. 27A-27EThis illustration shows how the proximal surface 1638 of shelf 1634 prevents axial movement of the conveyor 1540 toward the proximal end of housing body 2002. Axial movement toward the proximal end is prevented after the distal surface 1636 of shelf 1634 and the conveyor retaining surface (e.g., shoulder 2020) disengage. The proximal surface 1638 abuts against the distal end of shoulder 2020, thereby preventing axial movement of the conveyor 1540 toward the proximal end of housing body 2002. The distal end of the conveyor retaining surface may be a flat or substantially flat surface to prevent the proximal surface 1638 from pushing past the conveyor retaining surface.

[0311] As described above, the analyte monitoring device may include a housing. The housing may at least partially surround or enclose other components of the analyte monitoring device (e.g., electronic components), for example, to protect these components. For instance, the housing may be configured to help prevent dust and moisture from entering the analyte monitoring device. In some variations, an adhesive layer may allow the housing to adhere to a user's surface (e.g., skin) while allowing the microneedle array to extend outward from the housing and into the user's skin. Furthermore, in some variations, the housing may typically include rounded edges or corners and / or a low profile to prevent damage and reduce interference with clothing, etc., worn by the user.

[0312] For example, such as FIG. 27E As shown, an example variant of the analyte monitoring device 300 may include a housing 310 and a microneedle array 331, the housing 310 being configured to at least partially enclose other various internal components of the device 300, and the microneedle array 331 extending outward from the skin-facing surface (e.g., the underside) of the housing 310.

[0313] For example, housing 310 may include one or more rigid or semi-rigid protective housing components, which may be connected together by suitable fasteners (such as mechanical fasteners), mechanical interlocks or mating features and / or engineering fits. For example, as FIG. 27E As shown, the housing may include a housing cover 310a and a housing base 310b, wherein the cover 310a and the base 310b may be secured together using one or more threaded fasteners (e.g., fasteners engaging threaded holes in the upper and / or lower housing portions). The cover 310a and the base 310b may include rounded / rounded edges and corners, and / or other damage-resistant features. When joined together, the cover 310a and the base 310b may form an internal volume that houses other internal components, such as a device printed circuit board 351 (PCB), a sensor assembly 321, and / or other components, such as a gasket 312. For example, the internal components arranged in the internal volume may be arranged in a compact, low-profile stack, such as... FIG. 27E As shown. Although FIG. 27DA housing 310 comprising multiple housing components is shown, but in some variations, housing 310 may include a single component defining an internal volume for accommodating internal device components. In some embodiments, housing 310 may be filled with a suitable potting compound (e.g., epoxy resin) to reduce harmful environmental impacts such as temperature, humidity, pressure, and light.

[0314] In addition, the analyte monitoring device 300 may include an adhesive layer 340 configured to attach the housing 310 to a user's surface (e.g., skin). The adhesive layer 340 may be attached to the skin-facing side of the housing 310, for example, via a double-sided adhesive pad 345. FIG. 27C As illustrated in the variant depicted. Alternatively, the adhesive layer 340 can be directly attached to the skin-facing side of the housing 310 using one or more suitable fasteners (e.g., adhesive, mechanical fasteners, etc.). The adhesive layer 340 can be protected by a release liner, which the user removes before application to the skin to expose the adhesive. In some variants, the analyte monitoring device may include a feature that allows the analyte to be detected from the skin. Obtained 1504XL TM Double-sided adhesive and 4076 TM Skin-facing adhesives. These materials were chosen for their: breathability, abrasion resistance, average water vapor transmission rate (MWVTR), biocompatibility, compatibility with sensor sterilization methods / strategies, appearance, durability, tackiness, and ability to maintain said tackiness during sensor wear.

[0315] In some variations, the periphery of the adhesive layer 340 may extend further than the periphery or outer periphery of the housing 310 (e.g., to increase the adhesion surface area, improve retention stability, or enhance adhesion to the user's skin). Furthermore, in some variations, the adhesive layer 340 may include an opening 342 that allows the outwardly extending microneedle array 331 to pass through. The opening 342 may closely / closely externally / definite the shape of the microneedle array 331, such as... FIGS. 27A-27E As shown (e.g., a square opening that closely corresponds in size and shape to a square microneedle array), or another suitable size and shape having a larger coverage area than the microneedle array (e.g., a circular opening larger than a square microneedle array).

[0316] although FIGS. 28A-28C The housing 310 shown is hexagonal and generally prismatic; however, it should be understood that in other variations, the housing 310 can be any suitable shape. For example, in other variations, the housing can be generally prismatic and have an elliptical (e.g., circular), triangular, rectangular, pentagonal, or other suitable shaped base. As another example, FIGS. 28A-28CAn example variation of an analyte monitoring device 400 is shown that includes a dome-shaped housing 411. While the dome-shaped housing 411 shown in FIGS. 1-3 is generally circular, in other variations the dome-shaped housing can have a base with another suitable elliptical or polygonal shape. FIG. 28D

[0317] Similar to the housing 310, the housing 411 can include an interior volume configured to at least partially enclose other components of the analyte monitoring device 400. For example, as shown in the cross-sectional view of FIG. 4, the housing 411 can include a dome-shaped cover 411a coupled to a base 411b so as to form an interior volume in which a device PCB 451 and a sensor assembly having a microneedle array 431 can be disposed. Further, the housing 411 can be configured to be coupled to a surface by an adhesive layer 440, and the microneedle array 431 can extend outwardly from the housing and beyond the adhesive layer 440. Further, as shown in FIGS. 4 and 5, the adhesive layer 440 can extend beyond the outer perimeter of the housing 411. FIG. 28D FIG. 29 28E

[0318] In some variations, the analyte monitoring system can provide user status, analyte monitoring device status, and / or other suitable information on the analyte monitoring device directly through a user interface (e.g., a display, indicator lights, etc. as described below). Thus, in some variations, such information can be provided directly by the analyte monitoring device as compared to analyte monitoring systems that can only transmit information to a separate peripheral device (e.g., a mobile phone, etc.) that in turn communicates the information to the user. Advantageously, in some variations, such a user interface on the analyte monitoring device can reduce the need for a user to continually maintain a separate peripheral device (which can be impractical due to cost, inconvenience, etc.) in order to monitor user status and / or analyte monitoring device status. Further, a user interface on the analyte monitoring device can reduce the risk associated with a loss of communication between the analyte monitoring device and a separate peripheral device, such as a user having an inaccurate understanding of their current analyte level (e.g., causing a user to believe their analyte level is high when in fact it is low, which can for example cause the user to self-administer an inaccurate dose of medication or cause the user to refuse a therapeutic intervention when medically necessary).

[0319] Further, such an ability to communicate information to a user through the analyte monitoring device itself, without reliance on a separate peripheral device, can reduce or eliminate the need to maintain compatibility between the analyte monitoring device and such a peripheral device upon upgrade of the separate peripheral device (e.g., replacement with a new device model or other hardware, running a new version of an operating system or other software, etc.). ​​​​

[0320] Accordingly, in some variations, the housing can include a user interface, e.g., an interface that provides information in a visual, audible, and / or tactile manner, to provide information regarding user status and / or analyte monitoring device status, and / or other suitable information. Examples of user status that can be communicated via the user interface include information representative of analyte measurements in the user (e.g., below a predetermined target analyte measurement threshold or range, within a predetermined target analyte measurement range, above a predetermined target analyte measurement threshold or range, an increase or decrease in analyte measurement over time, a rate of change of analyte measurement, other information related to trends in analyte measurements, other suitable alerts associated with analyte measurements, etc.). Examples of analyte monitoring device status that can be communicated via the user interface include device operational modes (e.g., associated with a device warm-up state, an analyte monitoring state, a battery power state such as low power, etc.), device error states (e.g., operational errors, pressure-induced sensing degradation, malfunctions, failure modes, etc.), device power states, device life status (e.g., end of expected sensor life), connection status between the device and a mobile computing device, etc.

[0321] FIG. 33A Another example variation of a microneedle 900 is shown having a generally cylindrical body portion. The microneedle 900 can be similar to the microneedle 700 as described above, except as described below. For example, similar to the microneedle 700, the microneedle 900 can include a cylindrical body portion 912 and a tapered distal portion 914 that terminates at an insulated distal tip 916. The microneedle 900 can also include a ring electrode 920 that includes an electrically conductive material and is disposed on the tapered distal portion 914 at a location that is proximal to (or offset or spaced apart from) the distal tip 916. Other elements of the microneedle 900 have similar reference numerals to corresponding elements of the microneedle 700.

[0322] However, in comparison to the microneedle 700, the microneedle 900 can have a sharper tip at the distal tip 916 and have an improved insulating sheath 913. For example, the distal tip 916 can have a sharper vertex angle (e.g., a vertex angle of about 25 degrees to about 45 degrees) and have a tip radius that is less than about 100 nanometers, which provides a sharper microneedle profile that can penetrate the skin more easily, at lower velocity, with less energy, and / or with less trauma. In addition, the insulating sheath 913 can be more robust than the insulating sheath 713 (as described above with respect to the microneedle 700), which can provide improved protection of the electrically conductive material of the ring electrode 920 from the skin and other environmental factors. FIG. 29As shown, the improved insulating sleeve 913 can extend only through the substrate 902, compared to (where it extends through the substrate 702 and along the height of the microneedle body portion 712). This allows the interlayer structure filling the trench (e.g., generated by DRIE as described above) to form an burial feature only within the substrate. Although the sidewalls of the microneedle 900 are shown in Figure 28 as extending approximately orthogonally to the substrate surface, it should be understood that because the improved insulating sleeve 913 does not need to extend the entire height of the microneedle body portion 712, in some variations the sidewalls of the microneedle 900 can be at a non-orthogonal angle relative to the substrate (e.g., the sidewalls can have a slight positive taper of about 1 degree to about 10 degrees, or about 5 degrees to about 10 degrees).

[0323] In some variations, the remainder of the microneedle surface 900 (excluding the annular electrode 920) may include an insulating material extending from the substrate insulator 904. For example, a layer of insulating material (e.g., SiO2) may extend from the front surface of the substrate 902 to provide a body portion insulator 918, and may further extend upwards to the proximal edge of the electrode 920, such as... FIG. 30 As shown. Another area of ​​insulating material can similarly cover the distal edge of electrode 920 and insulate the distal vertex 916. This area of ​​insulating material and / or an improved insulating sheath 913 can help prevent electrical contact between the conductive core 940 and the surrounding substrate 902. Thus, similar to microneedles 700, microneedles 900 can remain electrically insulated for individual addressing within the microneedle array. In some variations, the process of forming microneedles 900 can result in higher yields and / or provide lower production costs compared to the process of forming microneedles 700.

[0324] The microneedle 900 can have any suitable size. For example, in some variations, the microneedle 900 can include a height of about 400 μm to about 600 μm or about 500 μm. In some variations, the distal tapered portion 914 can have a tip angle of about 25 degrees to about 45 degrees and a tip radius of less than about 100 nm. Furthermore, the microneedle can have an axial diameter of about 160 μm to about 200 μm. FIGS. 31A-31C Various other sizes of exemplary variants of columnar microneedles with tapered distal portions and annular electrodes, similar to the microneedle 900 described above, are shown.

[0325] Although FIG. 2A Exemplary variations of microneedle array configurations are illustrated, but it should be understood that these figures are not limiting, and other microneedle configurations (including different numbers and / or distributions of working electrodes, counter electrodes, and reference electrodes, as well as different numbers and / or distributions of effective electrodes and ineffective electrodes, etc.) may be applicable to other variations of microneedle arrays.

[0326] Such as the analytical monitoring device 110 FIG. 27EAs shown in the schematic, the electronics system 120 can be integrated within the housing 112, thus the electronics system 120 can be combined with the sensing element (e.g., microneedle array) as part of a single unit, in contrast to traditional CGM systems that typically integrate components in multiple physically distinct units. Further details of example variations of the electronics system 120 are described below.

[0327] In some variations, the analyte monitoring device can include one or more printed circuit boards (PCBs). For example, the analyte monitoring device can include at least one PCB in the sensor assembly 321, which includes a microneedle array, such as FIGS. 27F-27I as shown.

[0328] For example, as FIG. 27J shown, the sensor assembly 321 can include a sensor mount printed circuit board (PCB) 322 coupled to a connection printed circuit board (PCB) 324. The microneedle array 331 can be attached to the sensor mount PCB 322 (e.g., FR-4, PTFE, Rogers 4350B), for example, by a soldering process that incorporates epoxy underfill for mechanical strength. In some variations, an epoxy skirt can be deposited along the edges of the silicon microneedle array 331 to mitigate sharp edges in the above-described silicon cutting process. The epoxy can also provide a transition from the silicon substrate edge of the microneedle array silicon to the edge of the PCB 322. Alternatively, such epoxy can be replaced or supplemented by a rubber grommet or the like.

[0329] As FIGS. 27H-27J shown, the sensor mount PCB 322 can act as a standoff that at least partially determines a desired distance that the microneedle array 331 protrudes from the housing 310. Thus, the standoff height of the sensor mount PCB 322 can be selected to help ensure that the microneedle array 331 is properly inserted into the skin of a user. During the needle insertion process, the bottom face of the housing 310 will act as a stop for the needle insertion. If the sensor mount PCB 322 has a reduced height, and its lower surface is flush or nearly flush with the bottom face of the housing, then the housing 310 will prevent the microneedle array 331 from being fully inserted into the skin. However, increasing the standoff height can result in greater pressure of the microneedle array against the skin during the microneedle insertion process, which can result in skin irritation and / or erythema (skin redness).

[0330] The sensor mount PCB 322 can be secured to the housing 310 and / or within a laminate secured within the housing, for example, using suitable fasteners or the like. For example, as FIG. 27JAs shown, the sensor carrier PCB 322 (with the microneedle array 331) can be coupled to a first side of the connection PCB 324, while an opposite second side of the connection PCB 324 can be coupled to the interposer PCB connector 326. As FIG. 2A As shown, the interposer PCB connector 326 can be communicatively coupled to the device PCB 351, for example, for signal processing as described below. Thus, signals from the microneedle array 331 can pass through the sensor carrier PCB 322 and via the sensor carrier PCB 322, the connection PCB 324, and the interposer PCB connector 326 to the device PCB. However, in some variations, the analyte monitoring device can include fewer PCBs. For example, in some variations, the sensor assembly 321 can omit the sensor carrier PCB 322, such that the microneedle array 331 can be in direct electrical communication to the connection PCB 324 (or to the device PCB 351).

[0331] Additionally or alternatively, in some variations, at least one printed circuit board in the sensor assembly 321 can include or be coupled to one or more additional sensors in conjunction with the microneedle array 331. For example, the sensor assembly 321 can include a temperature sensor (e.g., a thermistor, a resistance temperature detector, a thermocouple, a bandgap reference, a non-contact temperature sensor, etc.). In some variations, temperature measurements can additionally or alternatively be performed by one or more electrodes in the microneedle array that are not sensitive to the analyte.

[0332] In some variations, the sensor carrier PCB 322 can have a thickness of about 0.05 inches to about 0.15 inches, or about 0.093 inches to about 0.127 inches. In some variations, the sensor carrier PCB 322 can include one or more conductive vias configured to route / direct electrical signals from a front surface of the PCB to a back surface of the PCB. In some variations, the sensor carrier PCB 322 can include a semiconductor (e.g., silicon) having conductive vias configured to route / direct electrical signals from a front surface of the semiconductor to a back surface of the semiconductor. In other variations, the microneedle array 331 can be mounted directly to the PCB 324 without the sensor carrier PCB 322.

[0333] In some variations, the electronic system of the analyte monitoring device can include an analog front end. The analog front end can include sensor circuitry (e.g., as FIG. 2AThe illustrated sensor circuit 124) converts the analog current measurements to digital values that can be processed by the microcontroller. For example, the analog front end can include a programmable analog front end suitable for electrochemical sensors. For example, the analog front end can include the MAX30131, MAX30132, or MAX30134 components (which have 1, 2, and 4 channels, respectively) available from Maxim Integrated (San Jose, CA), which are ultra-low power programmable analog front ends for electrochemical sensors. The analog front end can also include the AD5940 or AD5941 devices available from Analog Devices (Norwood, MA), which are high-precision impedance and electrochemical front ends. Similarly, the analog front end can also include the LMP91000 available from Texas Instruments (Dallas, TX), which is a configurable analog front end regulator for low-power chemical sensing applications. The analog front end can provide biasing and complete measurement paths, including an analog-to-digital converter (ADC). Ultra-low power can allow for continuous biasing of the sensor to maintain accuracy and fast response when measurements are needed for long periods of time (e.g., 7 days) using a body-worn battery-powered device.

[0334] In some variations, the analog front end device can be compatible with two- and three- terminal electrochemical sensors, for example, to enable DC current measurement, AC current measurement, and electrochemical impedance spectroscopy (EIS) measurement capabilities. In addition, the analog front end can include an internal temperature sensor and programmable reference voltage source, support for external temperature monitoring and external reference voltage source, and integrated voltage monitoring of bias and supply voltages to ensure safety and compliance.

[0335] In some variations, the analog front end can include a multi-channel regulator to multiplex sensor inputs and process multiple signal channels. For example, the analog front end can include a multi-channel regulator, such as the multi-channel regulator described in U.S. Patent No. 9,933,387, which is incorporated herein by reference in its entirety.

[0336] In some variations, the analog front end and peripheral electronics can be integrated into an application-specific integrated circuit (ASIC), for example, which can help reduce cost. In some variations, the integration scheme can include the following microcontroller.

[0337] In some variations, the electronics system of the analyte monitoring device can include at least one microcontroller (e.g., as described above in connection with the microcontroller 126) that is configured to perform the following functions. FIG. 2AThe microcontroller can include, for example, a processor with integrated flash memory. In some variations, the microcontroller in the analyte monitoring device can be configured to perform analysis to correlate the sensor signal to an analyte measurement (e.g., a glucose measurement). For example, the microcontroller can execute programmed routines in firmware to interpret the digital signal (e.g., from the analog front end), perform any relevant algorithms and / or other analysis, and route the processed data to and / or from the communication module. Keeping the analysis on the analyte monitoring device can, for example, enable the analyte monitoring device to broadcast / transmit analyte measurement results to multiple devices in parallel (e.g., a mobile computing device such as a smart phone or smart watch, a therapy delivery system such as an insulin pen or pump, etc.) while ensuring that each connected device has the same information.

[0338] In some variations, the electronic system of the analyte monitoring device can include at least one communication module (e.g., as shown in FIG. 1 12) that is configured to communicate with other devices (e.g., a mobile computing device such as a smart phone or smart watch, a therapy delivery system such as an insulin pen or pump, etc.). The communication module can be configured to communicate with other devices using any suitable communication protocol, including, for example, Bluetooth®, Bluetooth Low Energy, ANT+, ZigBee®, Wi-Fi®, Z-Wave®, Z-Wave Plus®, Thread®, and / or other suitable communication protocols. In some variations, the communication module can be configured to communicate with other devices using a proprietary communication protocol. In some variations, the communication module can be configured to communicate with other devices using a combination of communication protocols. FIG. 2AThe communication module 126 shown is, for example, a wireless communication module that communicates with one or more devices. For example, the communication module may include a wireless transceiver integrated into the microcontroller device. However, the electronic system may additionally or alternatively include a communication module separate from the microcontroller device. In some variations, the communication module may communicate via a wireless network (e.g., via Bluetooth, NFC, WiFi, RFID, or any type of cable-free data transmission). For example, devices may communicate directly with each other in paired connections (1:1 relationship, i.e., point-to-point transmission) or in a centrally radiating or broadcast connection (“one-to-many” or 1:m relationship, i.e., multipoint transmission). As another example, devices may communicate with each other via mesh network connections (e.g., “many-to-many”, or m:m relationship, or point-to-point (ad-hoc)), such as via a Bluetooth mesh network. Wireless communication can use any of a variety of communication standards, protocols, and technologies, including but not limited to Global System for Mobile Communications (GSM), Enhanced Data GSM Environment (EDGE), High-Speed ​​Downlink Packet Access (HSDPA), High-Speed ​​Uplink Packet Access (HSUPA), Evolution, Data-Only (EV-DO), HSPA, HSPA+, Dual-Cell HSPA (DC-HSPDA), Long Term Evolution (LTE), Near Field Communication (NFC), Wideband Code Division Multiple Access (W-CDMA), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Bluetooth, Wi-Fi (e.g., IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n, etc.), or any other suitable communication protocol. Some wireless network deployments may combine networks from multiple cellular networks or use a mix of cellular, Wi-Fi, and satellite communications. In an example variant, the communication module may include a wireless transceiver integrated into a microcontroller and a Bluetooth Low Energy compatible radio compliant with the Bluetooth Special Interest Group 5.0 specification.

[0339] The communication module may also include or be coupled to one or more antennas (e.g., such as...). FIG. 2B Antenna 128 is shown. For example, the electronic system may include a chip antenna mounted on a PCB, or an antenna directly implemented on a PCB, which can provide better range while reducing cost and complexity. In some variations, the user wearing the analyte monitoring device 110 can act as an antenna (e.g., antenna 128). For example, the antenna input / output section 128 of the communication module 126 can be electrically connected to a single microneedle or multiple microneedles inserted into the wearer's skin (e.g., similar to...). FIG. 2AThe microneedle array 140) shown. This can increase the effective cross-sectional area of the antenna, provide sufficient impedance matching between the antenna input / output of the communication module and free space, and / or help improve operating metrics such as antenna gain, antenna diversity, omni-directionality, and communication module receiver sensitivity / transmitter efficiency.

[0340] Devices can enter and exit the range of the communication module to make connections and reconnections, enabling seamless connection and transfer of information between devices by the user. In some variations, the microcontroller on each analyte monitoring device can have a unique serial number, which enables tracking of a particular analyte monitoring device during production and / or in-field use.

[0341] As described above, in some variations, in addition to the microneedle array, the analyte monitoring device can include one or more sensors. For example, the analyte monitoring device can include one or more temperature sensors configured to measure skin temperature, enabling temperature compensation of the analyte sensor. For example, in some variations, a temperature sensor (e.g., thermistor, RTD, semiconductor junction, bimetallic sensor, thermopile sensor) can be coupled to the device PCB within the housing such that the temperature sensor is disposed near the skin-facing portion or bottom of the housing 112. The housing can be thinned to reduce thermal resistance and improve heat transfer, improving measurement accuracy. Additionally or alternatively, a thermally conductive material can thermally couple a surface mount temperature sensor to the user’s skin. In variations where the temperature sensor is coupled to the device PCB near the microneedle array carrier sheet substrate, a thermally conductive material can be, for example, molded into a skirt to mitigate the sharp edges of the carrier sheet and wrap along the edges of the carrier sheet and along the surface of the main PCB.

[0342] In some variations, the temperature sensor can be used to develop a glucose interpolation characteristic based on the measured current and a priori sensitivity (e.g., nA / mM or pA / mg / dL). In the case where temperature is constant, the current characteristic can be modeled by the following relationship: y = m G [G], where y is the measured current, m G is the glucose sensitivity, and [G] is the interpolated glucose concentration. In some cases, for example, introducing a channel b that is not sensitive to the analyte, a background signal can be introduced to the above equation: y = m G [G] + b. Introducing a measurement from a temperature sensor, the current characteristic can be represented by the following relationship: y = m G [G] + m T [T] + b, where m THere, T is the temperature sensitivity (e.g., pA / ℃), and b is the background signal (e.g., pA). In other operating conditions, the current characteristics are modeled by the following relationship: y = m1[G][T] + b, where m1 is a priori determined weighting factor. In other operating scenarios, the current characteristics can be modeled as the convolution of temperature and glucose: y = {m... T [T]+m2}[G]+b, where m2 is a priori determined weighting factor. In other operating conditions, the current characteristic is provided by the following relationship: y={m G [G]+m2}[T][G]+b. Under other operating conditions, the current characteristics are given by the following nonlinear relationship: y={m G2 [G] 2 +m G [G]}[T]+b, where m G2 It is a nonlinear weighting factor. Under other operating conditions, the current characteristics are given by the following Gaussian relationship: y = m G [G]exp{-([T]–[T OPT ]) 2 / (2σ 2 )}+b, where T OPT It is the optimal temperature for the enzyme's maximum catalytic conversion, and σ is the operating temperature range of the enzyme.

[0343] In some variations, the analyte monitoring device may include at least one microneedle with electrodes configured to function as an analyte-insensitive channel (e.g., a glucose-insensitive channel) with known temperature sensitivity, which can be used to compensate for temperature. For example, an advantage of using a glucose-insensitive channel includes proximity to the glucose sensor (e.g., resulting in smaller errors from thermal gradients) and cost (e.g., by reducing external components and the specialized process of thermally coupling the sensor to the skin). In some variations, the analyte monitoring device may include both the analyte-insensitive channel and a thermistor, with algorithms utilizing information from both. Additionally or alternatively, the analyte monitoring device may include an additional sensor measuring ambient temperature, which can also be used in temperature compensation algorithms.

[0344] In some variations, the analyte-insensitive channel can be used for differential measurements and / or to subtract the background noise level from the analyte-sensitive channel to improve signal fidelity and / or signal-to-noise ratio. The analyte-insensitive channel may be sensitive to common-mode signals that also occur in the analyte-sensitive channel (e.g., endogenous and pharmacological interferences, pressure attenuation, etc.).

[0345] Additionally or alternatively, in some variations, the analyte monitoring device may include at least one kinetic sensor / motion sensor. The motion sensor may include, for example, an accelerometer, gyroscope, and / or inertial measurement unit to capture position, displacement, trajectory, velocity, acceleration, and / or device orientation values. For example, such measurements can be used to infer the wearer's physical activity (e.g., steps, vigorous exercise) over a finite duration. Additionally or alternatively, in some variations, the motion sensor may be employed to detect interactions between the wearer and the analyte monitoring device (e.g., touch or tap). For example, touch or tap detection may be used to mute or pause notifications, alerts, and alarms; control wirelessly connected mobile computing devices; or enable / disable a user interface (e.g., an embedded display or indicator light) on the analyte monitoring device. Touches or taps may be performed in a defined sequence and / or for a predetermined duration (e.g., at least 3 seconds, at least 5 seconds) to trigger certain actions (e.g., deactivating / activating the display or indicator light). Additionally or alternatively, in some variations, such as when restricted motion or activity (e.g., without significant acceleration) is detected for at least a predetermined period of time (e.g., 15 minutes, 30 minutes, 45 minutes, 1 hour, or other suitable time) as measured by a motion sensor, the analyte monitoring device may enter a power-saving mode.

[0346] Additionally or alternatively, in some variations, the analyte monitoring device may include at least one real-time clock (RTC). The RTC can be used to track absolute time (e.g., Coordinated Universal Time, UTC, or local time) while the analyte monitoring device is in storage or during use. In some variations, synchronization with absolute time may be performed after the analyte monitoring device has been manufactured. The RTC can be used to time-stamp analyte measurements (e.g., glucose measurements) during operation of the analyte monitoring device to create a time-series dataset that is transmitted to connected peripheral devices (e.g., mobile computing devices), cloud storage, or other suitable data storage devices, for later viewing, for example, by users (e.g., wearers of the analyte monitoring device), their support networks, or their healthcare providers.

[0347] like FIG. 1 As shown, the analyte monitoring device may include one or more power sources 130 (such as batteries) within a housing 112, configured to power other components. For example, the analyte monitoring device may include an AgO battery, which has high energy density and is more environmentally friendly than lithium batteries. In some variations, primary (e.g., non-rechargeable) batteries may be used. Furthermore, in some variations, secondary (e.g., rechargeable) batteries may be used. However, any suitable power source may be used, including lithium-based batteries.

[0348] In some variations, a low-profile seat or mount can be used to connect the power source to the device PCB, which reduces the overall height of the electronics and thus minimizes the height or profile of the analyte monitoring device. For example, while a traditional battery seat uses a spring force of a conductive metal to apply force to the top side of the battery, in some variations, a laterally mounted battery seat can contact the side of the battery to complete the circuit. In some variations, the size and / or shape of the housing can be determined to have appropriate tolerances to apply a vertical or downward force on the battery toward the device PCB, thereby maintaining contact of the battery with the PCB.

[0349] In some variations, the analyte monitoring device can be applied manually. For example, a user can remove a protective film over an adhesive layer and manually press the device onto a desired wear site on his or her skin. Additionally or alternatively, as shown in FIG. 1 1 1, in some variations, an analyte monitoring device can be applied to the skin using a suitable applicator 160. The applicator 160 can be configured, for example, to push the analyte monitoring device 1 10 toward the user's skin such that the microneedle array 140 of the analyte monitoring device 1 10 can be inserted into the skin (e.g., to a desired target depth). Various exemplary variations of applicators for applying analyte monitoring devices are described below. FIGS. 31A-31D

[0350] In some variations, an applicator can include an actuatable housing, a trigger, and a delivery member. The delivery member can releasably receive (e.g., grasp, enclose, or otherwise carry) an analyte monitoring device. Generally, the housing, trigger, and delivery member can be joined to one another by one or more releasable coupling features such that, in an application procedure, actuation of the housing (e.g., directly or indirectly manually actuated by a user, or by an additional external actuator) can cause a change in state of the trigger, which in turn can cause a change in state of the delivery member to release the analyte monitoring device from the delivery member. For example, the housing, trigger, and delivery member can be axially aligned (e.g., concentric) and / or nested together. The components of the applicator can be formed using any suitable manufacturing process, including injection molding, casting, 3D printing, machining techniques (e.g., with a mill or lathe), and the like.

[0351] ​For example, the housing can include at least one trigger-retaining surface, the trigger can be disposed in the housing, and include at least one trigger member that releasably engages with the trigger-retaining surface. The delivery member can be releasably engaged with the trigger by one or more releasable coupling features, and can be configured to receive the analyte monitoring device. The delivery member can have a first, "carrying," configuration or form in which the delivery member holds the analyte monitoring device, and a second, "releasing," configuration or form in which the delivery member releases the analyte monitoring device. In response to actuation of at least a portion of the housing toward the delivery member (e.g., the applicator can be placed in compression, e.g., against a patient surface), the trigger member can disengage from the trigger-retaining surface of the housing, which can result in release of the releasable coupling features coupling the delivery member and the trigger. As a result, the delivery member can transition from its carrying configuration to its releasing configuration, thereby allowing deployment of the analyte monitoring device from the applicator.

[0352] Further, in some variations, e.g., as described below, the applicator can include one or more biasing elements (e.g., springs) disposed to urge apart adjacent components. For example, in some variations, the applicator can include at least one biasing element disposed between the actuatable housing and the trigger, such that upon actuation of the housing during an application procedure, such biasing element can provide a trigger force to the trigger that causes the trigger to disengage from the trigger-retaining surface of the housing. Additionally or alternatively, the applicator can include at least one biasing element disposed between the trigger and the delivery member. This biasing element can be loaded to store potential energy prior to actuation of the housing (e.g., the biasing element can comprise a compression spring that is pre-compressed prior to actuation of the housing). When the delivery member disengages from the trigger as a result of the housing being actuated during an application procedure, the energy stored in the loaded biasing element can be transferred to the delivery member, thereby driving the analyte monitoring device with a suitable application force (e.g., for a suitable skin penetration).

[0353] FIG. 31D An example variation of an applicator 1600 for an analyte monitoring device is depicted. The applicator 1600 includes an actuatable housing 1620, a trigger 1631 disposed in the housing 1620, and a delivery member 1651 disposed in the trigger 1631. As shown, a first biasing element 1628 (e.g., a compression spring) can be disposed between the housing 1620 and the trigger 1631, and a second biasing element 1648 (e.g., a compression spring) can be disposed between the trigger 1631 and the delivery member 1651. As described above and as shown, an analyte monitoring device 10 can be housed in the delivery member 1651, with a microneedle array facing in a distal direction away from the housing 1620. A cap 1608 can be removably coupled to the housing 1620 to fully enclose the analyte monitoring device 10 within the housing (e.g., to maintain a sterile state of the device 10 prior to application). FIG. 31C FIGS. 32A-32G As shown, a first biasing element 1628 (e.g., a compression spring) can be disposed between the housing 1620 and the trigger 1631, and a second biasing element 1648 (e.g., a compression spring) can be disposed between the trigger 1631 and the delivery member 1651. As described above and as shown, an analyte monitoring device 10 can be housed in the delivery member 1651, with a microneedle array facing in a distal direction away from the housing 1620. A cap 1608 can be removably coupled to the housing 1620 to fully enclose the analyte monitoring device 10 within the housing (e.g., to maintain a sterile state of the device 10 prior to application).​

[0354] refer to FIG. 32C The description further details the conveyor 1651, which may include a base portion having one or more flexible members 1662 extending from the conveyor core 1652, wherein the flexible members 1662 define a receiving portion 1660 for accommodating the analyte monitoring device 10. For example, as... FIG. 32C As shown, the flexible member 1662 includes an arcuate or helical member attached to the proximal end of the conveyor core 1652. The flexible member 1662 may be arranged circumferentially around the conveyor core 1652 to define a generally circular receiving portion 1660 adjacent to the coverage area of ​​the analyte monitoring device 10 for enclosing the analyte monitoring device 10. Although the conveyor 1651 is shown as having three flexible members 1662, it should be understood that in other variations, the conveyor 1651 may have any suitable number of flexible members (e.g., one, two, four, five, six or more).

[0355] Each flexible member 1662 may also include one or more connecting features (e.g., arranged at the distal end of the flexible member 1662), each connecting feature configured to mate with a corresponding connecting feature on the analyte monitoring device 10. For example, such as FIG. 31D As shown, at least one flexible member may include a tab 1664 or other protrusion that can be inserted into a corresponding opening 12 on the analyte monitoring device when the analyte monitoring device 10 is placed in the receiving portion 1660. FIGS. 32A-32G As shown in the diagram. When the flexible member 1662 is fully bent radially inward (“carrying configuration of the conveyor”) and the tab 1664 engages with the corresponding opening 12 on the analyte monitoring device, this engagement between the flexible member 1662 and the analyte monitoring device securely engages the analyte monitoring device within the receiving portion 1660. When the distal end of the flexible member 1662 is fully bent radially outward (“release configuration of the conveyor”), the tab 1664 can disengage from the opening 12 of the analyte monitoring device. As described in further detail below, this disengagement of the connecting feature structure on the conveyor and the analyte monitoring device allows the analyte monitoring device to be released from the applicator.

[0356] although FIGS. 32A-32G The conveyor shown has tabs as a connecting feature for securing the analyte monitoring device to the conveyor, but it should be understood that the conveyor may additionally or alternatively include other types of connecting features. For example, although FIGS. 32A-32GA generally rectangular tab on the flexible member is depicted, but the tab can have any suitable shape (e.g., triangular, circular, semi-circular, etc.) and / or suitable cross-sectional profile (e.g., the tab can have a substantially uniform thickness, or it can be thinner radially outward compared to the radially inner side attached to the flexible member 1662, making it easier for the tab to self-align and engage with the opening 12 on the analyte monitoring device). As another example, in some variations, the flexible member 1662 may include an opening at its distal end configured to receive a tab or other outward projection (not shown) on the analyte monitoring device.

[0357] although FIGS. 32A-32G A connection scheme is depicted in which the connecting feature structure on the flexible member 1662 is radially oriented inward to engage the side edge of the analyte monitoring device, but the connecting feature structure on the flexible member can be oriented in any suitable orientation to engage the analyte monitoring device. For example, in some variations, at least a portion of the flexible member 1662 may include a shoulder along its length, the shoulder forming a shoulder-like surface that supports the lower surface (e.g., the skin-facing surface) on which the analyte monitoring device rests. In these variations, similar to FIGS. 33A-33F In the variant shown, when the shoulder portion of the bendable member 1662 bends radially outward, the shoulder can detach from the lower surface of the analyte monitoring device, thereby allowing the analyte monitoring device to be released from the applicator.

[0358] Furthermore, different types of connection feature structures can be combined in a single transporter design. For example, the transporter may include at least one flexible member with a tab having an opening similar to that of a tab 1664 on an analyte monitoring device, at least one flexible member with an opening for receiving tabs on an analyte monitoring device, at least one flexible member with a shoulder, or any combination thereof.

[0359] FIG. 31C A detailed view of the trigger 1631 is depicted, which is configured to engage the conveyor 1651 housed therein, as shown. FIG. 33A As shown. For example, the conveyor 1651 may be substantially axially aligned with and nested within the trigger 1631, and the conveyor 1651 may move axially within the trigger 1631. When the trigger 1631 is activated by the actuation of the housing, its function is to disengage the analyte monitoring device from the conveyor 1651.

[0360] like FIG. 33GAs shown, the trigger 1631 can include a base portion 1633. The flexible member 1662 of the transfer member (when the transfer member is placed in the trigger) can generally be biased outwardly toward the interior of the base portion 1633. However, the effective inner diameter of the base portion 1633 can vary along the height of the base portion, which controls the degree to which the flexible member 1662 is allowed to flex outwardly. For example, the interior of the trigger 1631 can include one or more sloped edges against which the flexible member 1662 engages. The sloped edges can be, for example, on one or more angled trigger ribs 1639, as best shown in FIG. 33G FIG. 19, where the outwardly angled slope or ramp on the trigger rib 1639 allows the flexible member 1662 to flex radially outwardly as the transfer member moves away from the housing (e.g., downwardly in the orientation shown). In this way, if the transfer member is moved in a direction away from the housing, the flexible member 1662 can gradually flex outwardly and gradually transition the transfer member from its carried configuration to its released configuration. FIGS. 33A-33G

[0361] The rotational alignment of the transfer member 1651 within the trigger 1631 can be guided by one or more tracking features. For example, the trigger 1631 can include one or more tracks 1637 within which outward tracking features 1656 on the transfer member can travel. The tracks 1637 can include open slots as shown in FIG. 37A FIG. 19, or other suitable structures (e.g., recessed grooves or channels) against which the tracking features 1656 on the transfer member can slidingly engage. The tracks 1637 can also be configured to receive other suitable types of tracking features on the transfer member (e.g., ball bearings). Additionally or alternatively, the transfer member 1651 can instead include one or more tracks within which outward tracking features on the trigger can travel. The transfer member 1651 and / or the trigger 1631 can each include any suitable number of tracking features (e.g., one, two, three, four, or more), and the tracking features can be distributed circumferentially in equal or unequal fashion. For example, the transfer member can have two tracking features evenly distributed around the transfer member (180 degrees apart from one another, or directly opposite one another), or three tracking features evenly distributed around the transfer member (120 degrees apart from one another), or four tracking features evenly distributed around the transfer member (90 degrees apart from one another), and so on.

[0362] The crown portion 1641 of the trigger 1631 can be configured for controlling when the transfer member is able to move axially within the trigger. For example, as shown in FIG. 33A ​As shown, the crown portion 1641 of the trigger 1631 can receive and engage the conveyor core 1652, with a firing biasing element 1648 (e.g., a spring) disposed inside the conveyor core 1652 and loaded between the conveyor and the trigger. The crown portion 1641 can include one or more trigger members 1644 having a latch 1646 (e.g., a hook, a lip, and / or the like) that can engage a conveyor lip 1654 extending at least partially around the conveyor core 1652. The trigger members 1644 can include an elongated structure having a proximal end fixed to the base portion 1633 and a distal free end extending into the crown portion 1641. As FIGS. 34A-34G As shown, for example, the trigger members 1644 can include trigger retention slots 1644 (or channels, etc.) along their longitudinal length that engage the retention members 1617 of the housing. In some variations, one or more of the trigger members 1644 can have an arcuate cross-section with a radius of curvature similar to that of the rest of the crown portion 1641. The trigger 1631 can include any suitable number of trigger members 1644 (e.g., one, two, three, four, or more), and the trigger members can be distributed circumferentially equally or unequally. For example, the trigger can have two trigger members evenly distributed around the trigger (180 degrees apart from each other, or directly opposite each other), or three trigger members evenly distributed around the trigger (120 degrees apart from each other), or four trigger members evenly distributed around the trigger (90 degrees apart from each other), etc.

[0363] FIG. 37A A housing 1620 of the applicator 1600 is depicted. The housing 1620 can include a housing cavity that receives the trigger 1631 and the conveyor 1651. As FIG. 34B As shown, a first biasing element 1628 (e.g., a spring) can be disposed inside the housing cavity and on a mount 1642 and / or the like inside the housing cavity. The housing 1620 can be configured to be manipulated (e.g., manually by a user) to actuate the applicator 1600 to deploy an analyte monitoring device loaded within the conveyor 1651.

[0364] The housing 1620 can include one or more retention members 1617 within the housing cavity. The one or more retention members 1617 can include at least one trigger retention surface for releasably engaging the trigger member 1644 of the trigger 1631 and retaining the trigger in a cocked (unfired) state until the housing 1620 is actuated during an administration procedure. For example, the retention member 1617 can include a wall extending radially inward from an inner surface of the housing 1620 and engaging (e.g., interposing) into the trigger retention slot 1644 as described above. As such, the thickness of the retention member (measured in a circumferential direction around the housing 1620) can be close to the width of the trigger retention slot 1644. In some variations, the retention member 1617 can have a stepped profile, with one step configured to engage with the trigger member 1644 when the trigger is in the cocked state and another step configured to engage with the trigger member 1644 after the trigger has been actuated and is in the fired state, as described further below.

[0365] In some variations, the housing 1620 can include or be coupled to a grip 1613. For example, the grip 1613 can include a sheath or ring that slides around the housing 1620 or is coupled to the housing 1620 by a suitable mechanical fit, such as threads, an interference fit, etc. For example, as shown in FIG. 34A the housing can include one or more ribs 1611a configured to engage and rotate in alignment with the grip 1613 and / or shoulders 1611b configured to engage and axially align with the grip 1613. In some variations, the grip 1613 can be integrally formed with (e.g., overmolded with) the housing 1620 and / or the housing 1620 can include one or more gripping features described herein. In some variations, the grip 1613 can include one or more features for enhancing the ability of a user to manipulate the housing 1620. For example, the grip can include one or more recessed or otherwise indented profiles having finger-receiving surfaces to improve manual gripability, as shown in the housing 1620 in FIG. 34H or the housing 1620’ in FIG. 34I Additionally or alternatively, the grip can include one or more raised structural features (bumps, ridges, ribs, rings, etc.) to increase friction, as shown in the housing 1620” in FIG. 31D Additionally or alternatively, the grip 1613 can include one or more materials having greater friction (e.g., silicone / polysiloxane or other elastomers). The overall shape of the housing can vary. For example, the housing can generally be prismatic or domed and / or have a circular or polygonal cross-section, or any other suitable shape.

[0366] Further, in some variations, as described above with respect to FIG. 34HAs noted, the applicator can include an applicator cap 1608 coupled to the housing to enclose the analyte monitoring device 10 within the applicator and to help maintain the sterility of the analyte monitoring device 10 until it is applied to the user. Examples of other techniques to maintain the sterility of the analyte monitoring device 10 and that can be used in conjunction with the applicator are described in U.S. Patent Application No. 63 / 249,399, which is incorporated by reference herein. In some variations, the cap 1608 can be coupled to the housing 1620 by mechanical interfitting (e.g., threads, snap fit) and / or other suitable means (e.g., epoxy that can be overcome with sufficient applied separation force). Further, in some variations, the coupling of the cap 1608 and the housing 1620 can include one or more seals (e.g., gaskets). Similar to the grip 1613, the cap 1608 can include one or more features to enhance the ability of the user to manipulate the cap (e.g., to separate the cap from the housing prior to use of the applicator). For example, as shown in FIG. 34I the cap 1608’ can include ribs to increase the friction and gripability of the cap. As another example, as shown in FIGS. 35A-35B the cap 1608” can include concave features and a polygonal edge to enhance the gripability of the cap.

[0367] Turning now to use of the applicator 1600, FIGS. 36A-36C and FIG. 35A an example method of loading the analyte monitoring device 10 into the applicator 1600 is shown, such as during a manufacturing process. As noted above, the analyte monitoring device 10 can be inserted into or received by the carrier 1651. In particular, as shown in more detail in FIG. 36A and 35B the underside of the applicator, the analyte monitoring device 10 can be placed between the bendable members 1662 of the carrier (with the microneedle array pointing away from the housing). The analyte monitoring device 10 can be rotated into orientation so that its opening 12 is aligned with the tabs 1664 on the bendable members 1662, and the tabs 1664 can be inserted together into the opening 12 (or groove, etc.) so as to carry the analyte monitoring device 10 in the space between the bendable members 1662.

[0368] As shown in FIG. 36A the carrier 1651 with the analyte monitoring device 10 can be pushed into the interior of the trigger 1631 when the trigger 1631 is disposed within the housing 1620. As shown in the detail view of FIG. 37C as the carrier 1651 is pushed further into the trigger 1631, the carrier lip 1654 (which can be an outward protrusion positioned around at least a portion of the carrier core) can push into at least one trigger latch 1646 of the trigger. At least in part due to the carrier lip 1654 (e.g., FIG. 37Cthe inclined nature of the interface between the 1654') and the trigger latch 1646, advancing the conveyor lip 1654 into the trigger can push the trigger latch 1646 up and over the lower step portion of the stepped retention member 1617 of the housing FIG. 36B shown in FIG. 16A FIG. 36C ). When the trigger latch 1646 is pushed up over this lower step portion, the trigger member can flex radially outward, allowing the conveyor lip 1654 to pass by the trigger latch 1646. Once the conveyor lip 1654 is pushed further into the trigger and past the trigger latch 1646, the trigger latch 1646 is allowed to fall back into place on the lower step portion of the retention member 1617 FIGS. 37A-37E ). Once the trigger latch 1646 re-engages with the lower step portion of the retention member 1617, the conveyor lip 1654 is secured above the trigger latch 1646, locking the conveyor in place within the trigger and housing in the conveyor's carrying configuration, while locking the analyte monitoring device 10 in the conveyor.

[0369] FIG. 35B Other cross-sectional views of the coupling between the conveyor, trigger, and housing are shown when the analyte monitoring device is loaded in the applicator, and are further described below in alignment. FIGS. 36A-36C A lower side view of the analyte monitoring device 10 loaded in the applicator is also shown in FIG. 16B, showing the bendable members 1662 engaged with the openings 12 of the analyte monitoring device 10, and also locked into a radially inwardly flexed position (the carrying form of the conveyor) to secure the analyte monitoring device 10 in the applicator.

[0370] As described above, the analyte monitoring device 10 can be oriented with its openings 12 aligned with the tabs 1664 on the bendable members 1662, which can be inserted into the openings 12 in order to carry the analyte monitoring device 10 in the space between the bendable members 1662. When the conveyor is locked in place within the trigger, as described above with respect to FIG. 37E the bendable members 1662 are additionally pushed radially inward by the trigger ribs 1639 on the inside of the trigger FIG. 37A , such that the tabs 1664 are locked in the openings 12 of the analyte monitoring device 10.

[0371] Further, as FIG. 37AAs shown, a first biasing element 1628, such as a compression spring, can be disposed between the trigger and the housing in a relaxed or unloaded state. In this state, the first biasing element 1628 can urge the trigger and the housing apart, and when the housing is pushed into the trigger, the first biasing element transmits an actuation force to the trigger. In addition, a second biasing element 1648 can be disposed between the delivery member and the trigger in a compressed or loaded state, storing energy for forcibly ejecting the delivery member from the trigger to deploy the analyte monitoring device 2. Although the first and second biasing elements 1628 and 1648 are shown as compression springs in FIG. 37B FIG. 16, it should be understood that other biasing elements (e.g., spring arms, leaf springs, etc.) can additionally or alternatively be used as the first biasing element 1628 and / or the second biasing element 1648.

[0372] During the application procedure, at least a portion of the housing 1620 can be actuated toward the delivery member 1651 (or toward the trigger 1631). For example, at least a portion of the housing 1620 can be pushed or compressed. Alternatively, at least a portion of the housing 1620 can be rotated, tilted, or actuated in any manner to move the housing 1620 toward the delivery member and / or the trigger. The entire housing can be actuated, or can include a depressible button (or other suitable actuator) to effectuate similar mechanical force transmission as described below. Reference is made to FIG. 16. FIG. 38 When the housing 1620 is pushed toward the delivery member 1651 or the trigger 1631, the first biasing element 1628 compresses, which transmits or provides a trigger force to the trigger member 1644. This trigger force can cause the trigger member 1644 to disengage from the trigger retaining surface 1617a on the lower step portion of the retaining member 1617 and flex radially outward to move into the gap, resting on the second step portion 1617b of the retaining member 1617 in the housing. This outward movement of the trigger member 1644 causes the delivery member lip 1654 to disengage from the trigger member 1644, which unlocks the delivery member 1651 and allows it to move axially within the trigger 1631. When the delivery member 1651 is unlocked in this manner, the second biasing element 1648 relaxes and releases its stored energy to accelerate or forcibly eject the delivery member 1651 axially downward (in the direction of arrow 1652 in FIG. 16) out of the trigger 1631 and into the user’s skin. FIGS. 39A-39D(In the direction shown). The conveyor 1651 continues to move axially until the tracking feature structure 1656, engaged in the slot 1637 of the track, reaches the lower edge of the slot 1637 of the track. Simultaneously, as the conveyor 1651 moves axially downward, its flexible member 1662 is gradually allowed to bend radially outward from the carrier configuration of the conveyor to the release configuration of the conveyor, as permitted by the outwardly inclined surface or ramp on the trigger rib 1639. When the flexible member 1662 is fully radially outwardly bent, the flexible member 1662 disengages from the analyte monitoring device 10 to allow the analyte monitoring device 10 to completely separate from the applicator 1600. The longer the outwardly inclined surface or ramp on the trigger rib 1639, the later the flexible member 1662 bends outward and ultimately releases the analyte monitoring device 10. Thus, a longer inclined surface or ramp on the trigger rib 1639 can help ensure that the analyte monitoring device 10 remains in a fixed position for a longer period when the conveyor is released. During the application procedure, the analyte monitoring device 10 is ejected from the conveyor and thus from the applicator, but the conveyor 1651 is held in the trigger 1631 at least in part by the continuous engagement of the conveyor lip 1654 within the slot of the trigger member 1644.

[0373] FIG. 40A An exemplary variant of the applicator 2400, similar to the applicator 1600 described above, is depicted, with some differences as described below. For example, the applicator 2400 may include a housing 2410 (which may include or be coupled to a gripper 2412), a trigger 2430, and a conveyor 2450, all coupled to each other. A first biasing element 2428 may be arranged between the housing 2410 and the trigger 2430 to provide a triggering force, and a second biasing element 2448 may be arranged between the trigger 2430 and the conveyor 2450 to provide a firing force, similar to the first and second biasing elements described above with respect to the applicator 1600. The applicator 2400 may also include a cap 2408 removably coupled to the housing 2410, and the cap 2408 may be similar to the cap 1608 described above with respect to the applicator 1600.

[0374] refer to FIGS. 41A-41E and 40B The conveyor 2450 shown FIGS. 42A-42E The trigger 2430 shown and FIG. 43 The features shown in the detailed view of housing 2410 are described below, along with an operational description of applicator 2400. FIG. 43The applicator 2400 is shown in a loaded state, in which an analyte monitoring device 10 (not shown) can be carried in a receptacle in the conveyance 2450, defined at least in part by one or more coupling members 2464 and / or an annular rim (or partial annular rim) within which the analyte monitoring device can be placed or upon which it can rest. The conveyance 2450 can be engaged with the trigger 2430 such that the outer periphery of the conveyance 2450 can interfere with (e.g., press radially outward against) the inner sidewall surface of the trigger 2430, and the trigger sidewall urges the conveyance 2450 into a carrying configuration in which the coupling members 2464 lock around the analyte monitoring device 10. In some variations, the periphery of the conveyance 2450 can include one or more outwardly protruding members 2462 that engage with and travel within corresponding tracks 2416 (e.g., slots, grooves) in the trigger 2430 sidewall, thereby maintaining rotational alignment between the conveyance 2450 and the trigger 2430. The conveyance 2450 can include a conveyance stem 2452 that extends from a central portion of the conveyance 2450 and is configured to engage with a central opening between the collet arm-like blades 2432 of the trigger 2430. The blades 2432 can be arranged circumferentially around the trigger 2430. Each blade 2432 can have a proximal end that is integrated / integral with or otherwise attached to the periphery of the trigger 2430 (e.g., around an annular or partial annular base 2439, or at the sidewall of the trigger) to support the blade. Further, each blade 2432 can have a free distal end that extends toward the center of the trigger 2430, and have a surface 2432a that engages with a surface 2452a of the conveyance stem. Although the trigger 2430 is shown in the figures as including three blades, it will be appreciated that the trigger 2430 can include any suitable number of blades (e.g., one, two, four or more, etc.). The blades can be arranged in equal or unequal fashion circumferentially. For example, the trigger can have two blades evenly distributed around the trigger (180 degrees apart from each other, or directly opposite each other), or three blades evenly distributed around the trigger (120 degrees apart from each other), or four blades evenly distributed around the trigger (90 degrees apart from each other), etc.

[0375] The trigger 2430, in turn, can be engaged with the interior of the housing 2410. As FIG. 44The trigger tab 2436 is disposed around the exterior of the leaf 2438 and protrudes radially outward such that the interior side surface of the housing 2410 interferes with the tab 2436 and pushes the leaf 2438 inward. This radially inwardly directed force urges the leaf 2438 into a closed configuration around the delivery member rod 2452 and further axially locks the delivery member 2450 in a position engaged with the trigger 2430 where the second biasing element 2448 (e.g., a spring) is compressed or otherwise loaded with energy for firing the delivery member 2450 in response to trigger actuation. Further, similar to the applicator 1600, the first biasing element 2428 can be disposed between the housing 2410 and the trigger 2430 to provide a trigger force.

[0376] FIG. 44 The applicator 2400 is depicted in a fired state after the trigger 2430 has been activated (e.g., by actuating the housing 2410 toward the delivery member 2450 and / or the trigger 2430). For example, when at least a portion of the housing 2410 is pushed and actuated toward the delivery member 2450 and / or the trigger 2430, the housing 2410 moves toward the delivery member and / or the trigger and the tab 2436 on the trigger leaf 2432 slides into the track 2416 in the housing. When the trigger leaf 2432 is in the track 2416, this relieves the central pressure on the trigger leaf 2432 and allows the leaf 2432 to expand radially outward, causing the central opening to widen and release the delivery member rod 2452. Once the delivery member rod 2452 is released, the delivery member 2450 is free to move axially with the trigger (in the FIGS. 45A-45D The delivery member 2450 is free to move axially with the trigger (in the orientation shown, downward) to the point where the inner diameter of the trigger widens and allows the coupling member 2464 to flex radially outward and release the analyte monitoring device 10 in a delivery member released configuration. This axial movement of the delivery member 2450 can be accelerated by the second biasing element 2448 which pushes the delivery member 2450 and the analyte monitoring device 10 carried therein downward until the outwardly protruding member 2462 on the delivery member reaches and engages in the lowest edge of the track 2416. As a result, the analyte monitoring device 10 is ejected from the applicator 2400 and the fired delivery member 2450 remains within the trigger 2430.

[0377] FIGS. 46A-46EAn exemplary variation of an applicator 3000 similar to the above-described applicator 1600 is depicted, with certain differences as described below. For example, the applicator 3000 can include a housing 3010, a trigger 3030, and a delivery member 3050 coupled to one another. A first biasing element 3028 can be disposed between the housing 3010 and the trigger 3030 to provide a trigger force, and a second biasing element 3048 can be disposed between the trigger 3030 and the delivery member 3050 to provide a firing force, similar to the first and second biasing elements described above with respect to the applicator 1600. The applicator 3000 can also include a base ring 3006, which can be coupled to the housing 3010 (e.g., with one or more fasteners).

[0378] Reference is made to FIGS. 47A-47D the features described in the detailed views of the illustrated delivery member 3050, FIGS. 48A-48E the illustrated trigger 3030, and FIG. 49 the illustrated housing 3010, the following is a description of the operation of the applicator 3000. FIG. 49 The applicator 3000 is shown in a loaded state, with an analyte monitoring device (not shown) can be carried in a receptacle in the delivery member 3050, which is defined at least in part by one or more coupling members 3064 and / or an annular rim (or partial annular rim) within which the analyte monitoring device can be placed or on which it can be placed. The delivery member 3050 can be disposed inside the trigger 3030, with the receptacle portion (carrying the analyte monitoring device) engaging an inner sidewall surface 3036 of the trigger 3030. The tabs 3062 of the delivery member 3050 can engage tracks 3034 (e.g., grooves, channels) within the inner sidewall surface 3036, for example, to maintain rotational alignment between the delivery member 3050 and the trigger 3030. The delivery member 3050 can also have a delivery member mating connector 3052, which is centrally located on the delivery member and extends upward from the receptacle portion of the delivery member 3050 that carries the analyte monitoring device (in the direction of the arrow 3053) to engage a mating connector 3032 of the trigger 3030 (in the direction of the arrow 3033), for example, to maintain rotational alignment between the delivery member 3050 and the trigger 3030. FIG. 50In the illustrated orientation). The transfer member 3050 can be engaged with the housing 3010 by actuator members 3014 that extend longitudinally within a central portion of the housing 3010. Each actuator member 3014 can have an inner latch portion 3014a that extends through a corresponding opening in the transfer member mating connector 3052 and engages with the transfer member mating connector 3052. In addition, each actuator member 3014 can have an outer latch portion 3014b that engages with the trigger retention cylinder 3032 such that the actuator member 3014 can be constrained between the transfer member mating connector 3052 and the trigger retention cylinder 3032. In this way, the actuator members 3014 in this locked position hold the transfer member 3030 in a loaded position in which the load form of the transfer member holds the analyte monitoring device (as described above, the containment portion portion engages against the inner side wall surface 3036).

[0379] FIG. 50 The applicator 3000 is depicted in a fired state, and the trigger 3030 has been activated (e.g., by pushing and actuating the housing 3010 toward the transfer member 3050 and / or the trigger 3030). For example, when at least a portion of the housing 3010 is pushed and actuated toward the transfer member 3050 and / or the trigger 3030, the housing 3010 moves toward the transfer member and / or the trigger, and the actuator members 3014 are released from the trigger retention cylinder 3032. The freed actuator members 3014 are allowed to flex radially outward, which causes the inner latch portions 3014a to disengage from the transfer member mating connector 3052. Once the transfer member mating connector 3052 is disengaged and unlocked from the actuator members 3014, the transfer member 3050 is free to move axially within the trigger (in the illustrated orientation) to the inner side wall surface 3036 widens and allows the coupling member 3064 (which is hidden behind the analyte monitoring device 10 in the FIG. 50 illustrated orientation) to flex radially outward and release the point of the release form of the transfer member that releases the analyte monitoring device 10. FIGS. 51A through 51N

[0380] The axial movement of the transfer member 3050 is accelerated by the second biasing element 3048, which pushes the transfer member 3050 and the analyte monitoring device 10 carried therein downward until the transfer member tabs 3062 of the transfer member periphery reach the lowest edge of the track 3034 that the tabs 3062 engage. As a result, the analyte monitoring device 10 is ejected from the applicator 3000, and the fired transfer member 3050 is held within the trigger 3030.

[0381] ​The applicator variations described above (e.g., applicator 1600, applicator 2400, and applicator 3000) can each include a particular combination of housing, trigger, and conveyance variations that interact with one another. However, it should be understood that one or more features of the housing, trigger, and / or conveyance variations described herein can be combined in any suitable manner. Moreover, one or more features of the housing, trigger, and / or conveyance variations described herein can be combined with other housing, trigger, and / or conveyance designs not described herein. As such, any of the conveyance features described herein can be implemented with various implementations of triggers and / or housings. Similarly, any of the trigger features described herein can be implemented with various implementations of conveyances and / or housings, and any of the housing features described herein can be implemented with various implementations of conveyances and / or triggers.

[0382] For example, additional conveyance variations are described below that can be combined with any of the housing and / or trigger variations described above or any suitable housing and / or trigger variations.

[0383] Reference is made to ​ Another conveyance variation 3600 is depicted that includes a deformable ring. In Figures 51A-51F Aspects of the conveyance 3600 are depicted in Figure 51A , Figure 51B and Figure 51C A bottom perspective view, side view, and bottom view of a first implementation of the conveyance 3600 are depicted. Figure 51D , Figure 51E and Figure 51F A bottom perspective view, side view, and bottom view of a second implementation of the conveyance 3600 are depicted.

[0384] The bottom ring portion 3610 of the conveyance 3600 can be configured to hold the analyte monitoring device in a constrained (e.g., closed, stored, or otherwise carried) configuration. The bottom ring portion 3610 can be configured to release the analyte monitoring device in an expanded (e.g., open or released) configuration.

[0385] In a first implementation, as shown in Figure 51A , 51B and 51C, the bottom ring portion 3610 can be generally elliptical or ovoid in the constrained configuration. In the expanded configuration, the bottom ring portion can be generally circular. In the constrained configuration, the analyte monitoring device can contact an inner sidewall of the bottom ring portion 3610, while in the expanded configuration, the analyte monitoring device does not contact the inner sidewall of the bottom ring portion 3610, thereby allowing the analyte monitoring device to be released.

[0386] In a second implementation, as shown in Figure 51D , 51EAs shown in FIG. 51F, the bottom ring portion 3610 can be generally triangular in the constrained configuration; for example, the bottom ring portion 3610 can have a trilobal shape. In the expanded configuration, the bottom ring portion can be generally circular. When the bottom ring portion 3610 is in the constrained configuration, the triangular shape provides three points of contact between the wearable device and the inner sidewall of the bottom ring portion 3610.

[0387] The delivery member 3600 has two or more moveable ribs 3620 that facilitate m...

Claims

1. An applicator for an analyte monitoring device, the applicator comprising: a housing comprising a main body defining a cavity therein, wherein the housing main body comprises a distal opening; a ferrule received within the cavity and comprising a lumen therethrough; and a delivery member slidably received within the lumen and configured to releasably retain the analyte monitoring device, wherein the applicator is movable between a retracted configuration, an extended configuration, and a release configuration, wherein in the retracted configuration, the analyte monitoring device is retained within the delivery member, and the distal edge of the ferrule and the delivery member are in a proximal-most position, in the extended configuration, the distal edge of the ferrule is in a distal-most position and the delivery member is in an intermediate position, in the release configuration, the analyte monitoring device is released from the delivery member, the distal edge of the ferrule is in an intermediate position, and the delivery member is in a distal-most position.

2. The applicator of claim 1, wherein in the retracted configuration, the distal edge of the ferrule and the delivery member are proximal of the distal opening of the housing main body, in the extended configuration, the distal edge of the ferrule is distal of the distal opening of the housing main body and the delivery member is proximal of the distal opening of the housing main body, and in the release configuration, the distal edge of the ferrule and the delivery member are both distal of the distal opening of the housing main body.

3. The applicator of claim 1, further comprising a base configured to be removably coupled to the housing main body at the distal opening.

4. The applicator of claim 1, further comprising a friction ring releasably engaged with the ferrule.

5. The applicator of claim 3, wherein, the housing main body further comprises a groove formed in a distal surface of the housing main body, and the base further comprises a wall circumferentially disposed about a proximal surface of the base that is releasably coupled to the base.

6. The applicator of claim 4, wherein, the housing main body further comprises a mount extending from a proximal end of the housing main body to the distal opening of the housing main body.

7. The applicator of claim 1, further comprising a locking member at least partially received in at least one side opening of the housing main body and releasably engaged with the ferrule.

8. The applicator of claim 7, wherein, when the applicator is in the retracted configuration, the locking member is engaged with the ferrule, thereby preventing distal movement of the ferrule toward the distal opening of the housing main body.

9. The applicator of claim 8, wherein, the engagement between the locking member and the ferrule comprises contact between an upper edge of the locking member and a retention lip of the ferrule.

10. The applicator of claim 1, wherein, the ferrule comprises one or more tracks within which a corresponding one or more tracking protrusions on the delivery member slidably engage, thereby maintaining alignment of the ferrule with the delivery member as the applicator is moved from the retracted configuration to the extended configuration and the release configuration.

Images