Patent Publication Number: US-2022225939-A1

Title: Wearable continuous analyte measurement devices, biosensor inserters, and methods of use

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This claims the benefit of U.S. Provisional Patent Application No. 63/140,180, filed Jan. 21, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety for all purposes. 
    
    
     FIELD 
     The present disclosure relates to wearable continuous analyte measurement (CAM) devices and to biosensor inserters configured to insert a biosensor of the wearable CAM device. 
     BACKGROUND 
     Continuous glucose monitoring, such as with a continuous glucose monitor (CGM), has become a routine sensing operation, particularly for sensing blood glucose in relationship to diabetes care. By providing real-time glucose monitoring that provides glucose concentration readings over time, therapeutic actions, such as insulin uptake or other actions, may be undertaken in a timely manner and the glycemic condition may be better controlled. 
     During CGM operation, a biosensor of a transmitter and sensor assembly is inserted subcutaneously and is continuously operated in an environment surrounded by tissue and interstitial fluid (ISF). The biosensor inserted under the skin provides a signal to a transmitter of the transmitter and sensor assembly, and that signal can be indicative of a patient&#39;s blood glucose level, for example. These measurements may be made intermittently and automatically many times throughout the day (e.g., every few minutes or at any other suitable interval). 
     The transmitter and sensor assembly is adhered to the outer surface of a user&#39;s skin, such as on the abdomen or on the back of the upper arm, while the biosensor is inserted through the skin so as to contact ISF. This skin insertion process may be referred to as “insertion.” Devices for carrying out this biosensor insertion may be referred to as “biosensor inserters.” 
     SUMMARY 
     In some embodiments, a CAM wearable device configured to measure an analyte concentration is provided. The CAM wearable device includes a primary portion comprising at least a sensor assembly comprising a biosensor, a secondary portion comprising a pocket configured to receive a transmitter unit and a sealable opening to the pocket, the sealable opening containing an adhesive on edges thereof, and a backing member provided over the adhesive wherein removing the backing member exposes the adhesive to seal the sealable opening and encapsulate the transmitter unit. 
     In some embodiments, a biosensor inserter configured to insert a biosensor of a wearable device is provided. The biosensor inserter includes a push member, a contact member translatable relative to the push member, and a relief formed in the push member or contact member, the relief configured to allow a secondary portion of the wearable device to be folded into the relief. 
     In further embodiments, a method of using a biosensor inserter to insert a biosensor of a wearable device is provided. The method includes providing a biosensor inserter comprising: a push member, a contact member translatable relative to the push member, a trocar assembly including a trocar, and a relief formed in the push member or contact member, the relief configured to allow a secondary portion of the wearable device to be folded into the relief, and a mechanism configured to translate the wearable device and insert the trocar, folding the secondary portion of the wearable device into the relief, contacting the contact member to a person&#39;s skin, pushing on the push member during a first portion of a stroke to cause translation and implantation of the trocar and biosensor, and continuing to push the push member causing the mechanism to retract the trocar assembly while leaving the biosensor implanted during a second portion of the stroke. 
     Other features, aspects, and advantages of embodiments in accordance with the present disclosure will become more fully apparent from the following detailed description, the claims, and the accompanying drawings by illustrating a number of example embodiments. Various embodiments in accordance with the present disclosure may also be capable of other and different applications, and its several details may be modified in various respects, all without departing from the scope of the claims and their equivalents. Thus, the description is to be regarded as illustrative in nature, and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings are to be regarded as illustrative in nature, and not as restrictive. The drawings are not necessarily drawn to scale. Like numerals are used throughout the drawings to denote like elements. 
         FIG. 1A  is a side perspective view of a biosensor inserter including an opened door enabling insertion of a wearable device in accordance with one or more embodiments provided herein. 
         FIG. 1B  is a side perspective view of a biosensor inserter including a closed door enabling folding of the wearable device into a recess in the biosensor inserter in accordance with one or more embodiments provided herein. 
         FIG. 2A  is a perspective view of a wearable device having a removable and reusable transmitter unit to be inserted and sealed into a pocket in accordance with one or more embodiments provided herein. 
         FIG. 2B  is a perspective view of a wearable device with a removable transmitter unit being installed in the pocket and illustrating various internal components and a hinge allowing localized bending and thus folding of the wearable device in accordance with one or more embodiments provided herein. 
         FIG. 2C  is a perspective view of a circuit board of a wearable device with a pogo pin type of electrical connector configured to electrically couple with a transmitter unit in the pocket in accordance with one or more embodiments provided herein. 
         FIG. 2D  is a perspective view of a wearable device illustrating the pocket and an opening configured to receive the transmitter unit in accordance with one or more embodiments provided herein. 
         FIG. 2E  is a perspective view of a wearable device illustrating the pocket and inclusion of an adhesive on edges of an opening to the pocket in accordance with one or more embodiments provided herein. 
         FIG. 2F  is a perspective view of a wearable device illustrating an addition of a backing member overtop of the adhesive in the opening in accordance with one or more embodiments provided herein. 
         FIG. 3A  is a cross-sectioned side view of a biosensor inserter illustrating a wearable device inserted in a receiver of a transmitter carrier in accordance with one or more embodiments provided herein. 
         FIG. 3B  is a cross-sectioned side view of a biosensor inserter illustrating the folding/bending of the wearable device about a hinge thereof and the closure of the door in accordance with one or more embodiments provided herein. 
         FIG. 3C  is a cross-sectioned side view of a biosensor inserter illustrating the translation of the trocar assembly to receive the biosensor in an open-sided groove therein in accordance with one or more embodiments provided herein. 
         FIG. 3D  is a cross-sectioned side view of a biosensor inserter illustrating the translation of the trocar assembly to insert the trocar and biosensor into the skin of the user in accordance with one or more embodiments provided herein. 
         FIG. 3E  is a cross-sectioned side view of a biosensor inserter illustrating the retraction of the trocar assembly to leave the biosensor inserted in the skin of the user in accordance with one or more embodiments provided herein. 
         FIG. 3F  is a cross-sectioned side view of a biosensor inserter illustrating separation of the biosensor inserter and the wearable device in accordance with one or more embodiments provided herein. 
         FIG. 3G  is a perspective side view of a trocar assembly and sensor assembly illustrating the threading and insertion of the biosensor into the open-sided groove of the trocar in accordance with one or more embodiments provided herein. 
         FIG. 3H  is a perspective side view of a trocar assembly and sensor assembly illustrating the biosensor inserted into the open-sided groove of the trocar in accordance with one or more embodiments provided herein. 
         FIG. 4  is a perspective view of a biosensor inserter illustrating insertion of a transmitter unit into a pocket of the wearable device in accordance with one or more embodiments provided herein. 
         FIG. 5  is a perspective view of a biosensor inserter illustrating removal of a backing member to expose adhesive and thus enable sealing of the opening to the pocket in accordance with one or more embodiments provided herein. 
         FIG. 6  is a perspective view of a biosensor inserter illustrating a cap being removed and the door shut thus folding a secondary portion including the transmitter unit of the wearable device into a relief in accordance with one or more embodiments provided herein. 
         FIG. 7  is a side view of a biosensor inserter illustrating a person pushing on a push member to insert a biosensor of the wearable device into the skin in accordance with one or more embodiments provided herein. 
         FIG. 8  is a side view of a biosensor inserter illustrating removal of the biosensor inserter and exposing the wearable device in a folded condition in accordance with one or more embodiments provided herein. 
         FIG. 9  is a side view of a person unfolding and then adhering the secondary portion of the wearable device to the skin in accordance with one or more embodiments provided herein. 
         FIG. 10  is a perspective view illustrating the medical waste and the recyclable components of the biosensor inserter in accordance with one or more embodiments provided herein. 
         FIG. 11  illustrates a flowchart of a method of using a biosensor inserter to insert a biosensor in accordance with embodiments provided herein. 
     
    
    
     DETAILED DESCRIPTION 
     A biosensor inserter is configured to implant (insert) a biosensor of a transmitter and sensor assembly into the skin of a person. In conventional biosensor inserters, a trocar is used as part of the biosensor inserter wherein the trocar aids in the insertion of the biosensor into the skin of the person. Once the biosensor insertion process is performed, the trocar is retracted by operation of the biosensor inserter and generally remains inside of the biosensor inserter. Because blood may contaminate the trocar and biosensor inserter, conventional biosensor inserters are typically treated as a biohazard and are disposed of as medical waste, much like sharps. 
     Prior biosensor inserter designs may be large and costly to manufacture and generate a large amount of waste, typically discarded as medical waste. Moreover, sensor and transmitter assemblies tend to be rigid and relatively costly to manufacture. In order to reduce the amount of medical waste generated through use of these biosensor inserters, embodiments of the present disclosure operate to minimize the size of the biosensor inserter. In one or more embodiments described herein, the size is reduced by reducing the footprint of the biosensor inserter. This is accomplished by facilitating a foldable wearable device that is configured to fold into a recess or relief of the biosensor inserter. Thus, the overall footprint of the biosensor inserter can be reduced substantially, such as by 50% or more. As such, a volume of the components of the biosensor inserter that are treatable as medical waste are also substantially reduced. Thus, the amount of medical waste to be disposed of is dramatically reduced. Moreover, less material is needed for the biosensor inserter so the cost can be substantially reduced as well. 
     In accordance with some embodiments of the disclosure, and as shown in  FIGS. 1A and 1B , a biosensor inserter  100  is provided that includes a push member  102  configured to be pushed by a user (the person receiving the biosensor or another person), a contact member  104  configured to contact the person&#39;s skin, and an internal mechanism ( 310 — FIGS. 3A-3F ) that is part of the biosensor inserter  100 , and that enables the insertion of a biosensor of a wearable device  101 . 
     In order to better understand the biosensor inserter  100 , it is desirable to first understand in more detail an example embodiment of a continuous analyte monitor wearable device  101  (otherwise referred to as “wearable device  101 ” herein) that is useable with the biosensor inserter  100 . Referring now to  FIG. 2A  through  FIG. 2F , an example embodiment of a wearable device  101  is described. Wearable device  101  comprises a primary portion  101 P and a secondary portion  101 S that is bendable and foldable relative to the primary portion  101 P. Primary portion  101 P comprises at least a sensor assembly  214 , which can be mounted to a circuit board  228 . As shown in  FIGS. 2B and 2C  sensor assembly  214  comprises a biosensor  214 B, which is a strand-like sensor element positioned in opening  228 O and that can be positioned in and extend within an aperture  215  formed in a body  226  of the wearable device  101 . A trocar assembly is receivable in the aperture  215 . (A trocar may also be referred to as an insertion portion.) 
     The secondary portion  101 S comprises a pocket  216  configured to receive a transmitter unit  110  and an opening  218  to the pocket  216 . The opening  218  is sealable by any suitable means such as by containing an adhesive  220  on at least some of the edges  222  thereof. For example, as shown, the pocket  216  may be formed by an internal space and the opening  218  can comprise a slit opening forming flaps  224 A,  224 B that are sealable to one another to form a sealed pocket. 
     Once an adhesive  220  is applied, a backing member  225  ( FIG. 2F ) can be provided over the adhesive  220 . Backing member  225  can be a thin plastic sheet folded partially back over itself, for example. Other configurations of the backing member  225  are possible. After the user inserts the transmitter unit  110  in the pocket  216  through opening  218  and connects the transmitter unit  110  to electrical connector  234  exposed in pocket  216  to make electrical connection therewith, the user can remove the backing member  225  by pulling on an exposed end  225 E thereof with thumb and finger. This operates to expose the adhesive  220  and seal the opening  218  and encapsulate the transmitter unit  110 . The elastic resilience of the body  226  may provide enough force to cause the flaps  224 A,  224 B to seal together, but if not the user may apply additional pressure to fully seal the edges of the flaps  224 A,  224 B to one another. 
     As should be understood, the transmitter unit  110  contains transmitter components configured and operational to wirelessly transmit data, such as measured analyte data, to a receiving unit, such as a reader or a smart phone executing a software application for storing and/or displaying analyte concentrations. Transmitter unit  110  can also include other electronic components, such as an analog front end for biasing the analyte sensor and for sensing current that passes through the biosensor, such as operational amplifiers, current sensing circuitry, etc. Other transmitter circuitry may include processing circuitry such as analog-to-digital converters for digitizing current signals, memory for storing digitized current signals, and a controller such as a microprocessor, microcontroller, or the like for possibly computing analyte concentration values based on measured current signals. 
     Now describing the biosensor inserter  100  and its operation in more detail, reference is made to  FIGS. 1A-1B  and  FIGS. 3A-3H . 
     Biosensor inserter  100  includes a push member  102  including a push element  302 P that extends downwardly from the underside of push member  102  and includes a contact end that engages with a pivot member  316 . The push element  302 P can be a rigid member and extends downwardly (as oriented in  FIG. 3A ) from the underside of the push member  102 . Received within the contact member  104  is a transmitter carrier  318 . Transmitter carrier  318  has the wearable device  101  coupled thereto. Wearable device  101  includes a transmitter unit  110  containing at least the transmitter electronics and radio, and may include all or most of the other electronics therein. Wearable device further includes the biosensor  214 B coupled thereto, which has a reading end that is received inside of the trocar  212 T (see below) for insertion by the trocar  212 T. 
     In some embodiments, the push member  102 , contact member  104 , pivot member  316 , and/or transmitter carrier  318  may be formed from a polymer including, but not limited to, plastics such as polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyvinyl chloride, polypropylene, polystyrene, acrylonitrile butadiene styrene (ABS), polycarbonate, nylon, acetal, polyphthalamide (PPA), polysulfone, polyethersulfone, polyetheretherketone (peek), polypropylene, and the like. Other materials may be used. 
     In more detail, the wearable device  101  is detachably mounted to the transmitter carrier  318  by any suitable mechanism. The transmitter carrier  318  is axially translatable relative to the contact member  104  and is configured to support the wearable device  101  during insertion of the biosensor  214 B. As shown, the primary portion  101 P of the wearable device  101  may include transmitter electronics, one or more power sources  232 A,  232 B ( FIG. 2B ), and a sensor assembly  214  that includes the biosensor  214 B. 
     In some embodiments, the biosensor  214 B used within the primary portion  101 P may include two electrodes and the bias voltage may be applied across the pair of electrodes. In such cases, current may be measured through the biosensor  214 B. In other embodiments, the biosensor  214 B may include three electrodes such as a working electrode, a counter electrode, and a reference electrode. In such cases, the bias voltage may be applied between the working electrode and the reference electrode, and current may be measured through the working electrode, for example. The biosensor  214 B may include an active region including one or more chemicals that undergo an analyte-enzyme reaction with the products they detect. The enzyme is immobilized on one or more electrodes to provide a reaction (e.g., redox reaction) with the analyte and generate a current at the electrodes. Example chemicals include glucose oxidase, glucose dehydrogenase, or the like for measuring glucose as an analyte. In some embodiments, a mediator such as ferricyanide or ferrocene may be employed at the active region. In general, any analyte that may be detected and/or monitored with a suitable sensor and for which suitable chemistry exists may be measured, such as glucose, cholesterol, lactate, uric acid, alcohol, or the like. An analyte is defined herein as a component, substance, chemical species, or chemical constituent that is measurable in an analytical procedure. 
     An example of the biosensor  214 B can be any suitable implantable sensor that can be implanted in the skin of a user, such as a strand-shaped sensor that is able to be received inside of the trocar  312 T of the trocar assembly  312  and that is able to sense an analyte concentration reading of an interstitial fluid under the skin. 
     The operation of the biosensor inserter  100  will now be described. In a first stage, the wearable device  101  is inserted into the opening  329  with the door  112  opened as shown in  FIG. 1A and 3A . The primary portion  101 P is received in retention features on the sides of the transmitter carrier  318 , such as curved features closely matching the sides of the primary portion  101 P, tabs, or other features that hold the primary portion  101 P sufficiently so that the secondary portion  101 S can be folded, but not so tightly that the wearable device  101  cannot be removed after insertion is completed. 
     As shown in  FIG. 3B , the door  112  is then closed, thus folding the wearable device  101  at the hinge  227 . Door  112  may include a suitable hinge at the lower end formed by posts of the door opening that interface with holes in the lower sides of the door  112  to form a pivot location for the door  112 , for example. In some embodiments, a snap fit retainer mechanism may be formed in the top of the door  112  and door opening to keep the door  112  closed. Other suitable configurations of door  112  may be used. 
     Next, as shown in  FIG. 3C , the cover  105  ( FIG. 1A and 1B ) may be removed from the biosensor inserter  100  and cap  328  may be removed from the bottom side of the wearable device  101 , such as by unscrewing a threaded portion thereof, and an adhesive backing may be removed from the primary portion  101 P to expose adhesive applied to that portion. The contact member  104  is placed in contact with the skin (skin shown as dot-dash line) and a force (indicated by vertically down oriented bold arrow) is applied on the push member  102  via being pushed thereon by the user (or another). This causes the pivot member  316  to translate vertically in a first portion of the stroke. 
     The posts of pivot member  316  extending from each lateral side thereof translate along slots  321  on side supports  323  of the transmitter carrier  318  formed on either side of the pivot member  316  (only one side shown; the other side being identical). Likewise, the trocar assembly  312  and trocar  312 T are translated toward the skin during the first portion of a stroke of the biosensor inserter  100 . 
     A pivot location of the pivot member  316  can be formed between the first end and the opposite end of pivot member  316 . For example, a pivot axis may be formed by the laterally extending features, such as cylindrical posts that project from the respective lateral sides of the body of the pivot member  316 . The laterally extending posts can be received in the slots  321  formed in opposite sides of the side supports  323  of the transmitter carrier  318 . The pivot member  316  can include a push element interface feature, which may comprise a pocket or other interface feature formed between the pivot axis and the latch end  316 L ( FIG. 3E ) that is configured to interface with and contact a contact end of the push element  102 P as described further below. Other suitable laterally extending features may be used to form the pivot, such as a removable axle, or the like. During a first portion of an insertion stroke, pivot member  316  contacts the contact member  104  and is prevented from rotating until a second portion of the insertion stroke when the pivot member  316  passes a latch  104 L. Other mechanisms that constrain rotation for the first portion of the stroke and then allow rotation for the retraction portion of the stroke may be used. 
     In one or more embodiments, the trocar assembly  312  includes a body  312 B ( FIG. 3G and 3H ) having a body geometry that rides in grooves  331  ( FIG. 3C ) formed on the inside of the opposed side supports  327  of the transmitter carrier  318  (only one shown, but the other is a mirror image). The body geometry of the body  312 B of the trocar assembly  312  can have a rectangular body shape, that properly aligns the trocar  212 T as the body  312 B descends along the grooves  331  and slots  329  as the forks  316 F drive the wings  312 W (See  FIG. 3G and 3H ). The pivot member  316  may straddle the outside of side supports  327  and engage wings  312 W. During this portion of the stroke, the biosensor  214 B, which extends downwardly from aperture  215  of the wearable device  101 , is aligned with, and received within a lengthwise open-sided groove  332  formed in a side of the trocar  212 T. 
     As shown in  FIGS. 3G and 3H , precise alignment between the trocar  212 T and the biosensor  214 B as the trocar  212 T descends is desirable. In some embodiments steering features may be formed in aperture  215  that may be used to steer and thus aid in ensuring that the biosensor  214 B is properly aligned with and is received in the lengthwise open-sided groove  332  and body groove  334  of the trocar  212 T and body  312 B as shown in  FIGS. 3G and 3H .  FIG. 3G  illustrates the sensor assembly  214  and biosensor  214 B prior to insertion during the ascending of the trocar assembly  312 , whereas,  FIG. 3H  illustrates biosensor  214 B properly aligned with and received in the lengthwise open-sided groove  332  and body groove  334  of the trocar  212 T and body  312 B after descending. 
     Next, as shown in  FIG. 3D , as the user continues to push on push member  102 , this further translates the transmitter carrier  318  and the wearable device  101  and inserts the trocar  212 T and the biosensor  214 B into the skin (outer skin surface shown dotted). 
     Next, as shown in  FIG. 3E , as the user continues to push on push member  102  the latch end  316 L of the pivot member passes by latch  104 L and the pivot member  316  can freely pivot about the end of slot  321  and cause the trocar assembly  312  and the trocar  212 T to be retracted as shown, thus leaving the biosensor  214 B implanted into the skin (outer skin surface shown dotted) while still connected to the internal electronics. 
     The latch  104 L comprises a latch surface (lower latch surface) that once passed by via motion of a latch end  316 L of the pivot member  316 , will allow a pivot member  316  to rotate ( FIG. 3E ). Latch  104 L may be formed as an opening in the sidewall of the contact member  104 . The latch  104 L can comprise a circumferentially disposed surface of a width wider than the latch end  316 L of the pivot member  316 . Up until when the latch end  316 L passes by the latch  104 L, the pivot member  316  is largely restrained from rotation. As shown, latch  104 L is part of a vertically extending cutout that may be closed at its lower end, for example. 
     As shown in  FIG. 3F , to separate the biosensor inserter  100  from the wearable device  101 , the user can pull on the contact member  104 . This pulls the secondary portion  101 S from the pocket formed by relief  108  and door  112 . Once the biosensor inserted  100  is completely removed, the user may remove the backing from the adhesive portion applied to the secondary portion  101 S and fold the secondary portion  101 S onto the skin and apply slight pressure to adhere the adhesive to the skin (See  FIG. 9 ). 
     Once removed, all of the biosensor inserter  100  can be discarded as medical waste. Because the footprint has been dramatically reduced, the volume, and thus cost, of the material is also dramatically reduced. 
     As should be understood, contact member  104  may be configured to be concentric with push member  102  and may be telescopic therewith. In some embodiments, push member  102  may include a first alignment feature such as a vertically extending groove or recess, and contact member  104  may include a second alignment feature, such as a vertically extending rib, that interfaces with the first alignment feature. Such alignment features may hold push member  102  and contact member  104  in rotational alignment to prevent rotation of the contact member  104  within the push member  102 , such as during the insertion and retraction portions of the stroke. Push member  102  and contact member  104  may be cylindrical, oval, oblong, elliptical, or any other suitable shape in transverse cross-section. In some embodiments, push member  102  and contact member  104  may not be concentric. 
     Referring now to  FIG. 4  through  FIG. 11 , an embodiment of a method  1100  of using a biosensor inserter (e.g., biosensor inserter  100 ) to insert a biosensor (e.g., biosensor  214 B) is described. The method  1100  comprises, in block  1102 , providing the biosensor inserter comprising: a push member (e.g., push member  102 ), a contact member (e.g., contact member  104 ) translatable relative to the push member, a trocar assembly (e.g., trocar assembly  312 ) including a trocar (e.g., trocar  212 T), and a relief (e.g., relief  108 ) formed in the push member or contact member, the relief configured to allow a secondary portion (e.g., secondary portion  101 S) of a wearable device (e.g., wearable device  101 ) to be folded into the relief, and a mechanism (e.g., mechanism  310 ) configured to translate the wearable device  101  and insert the trocar. 
     The method  1100  further includes, in block  1104 , folding the secondary portion (e.g., secondary portion  101 S) of the wearable device into the relief as shown in  FIG. 6  via closing door  112 , and in block  1106 , contacting the contact member (e.g., contact member  104 ) to a person&#39;s skin  750 , and, in block  1108 , pushing on the push member (e.g., push member  102 ) during a first portion of a stroke to cause translation of the wearable device and implantation of the trocar and biosensor. 
     The method  1100  comprises, in block  1110 , continuing to push the push member causing the mechanism to retract the trocar assembly while leaving the biosensor implanted during a second portion of the stroke as is shown in  FIG. 7 . 
     Prior to folding the secondary portion  101 S of the wearable device  101  into the relief  108 , the method  1100  can involve inserting a transmitter unit  110  into a pocket  216  ( FIG. 2F ) formed in the secondary portion  101 S through an opening  218 , such as through slit opening shown in  FIG. 4 . Sides of the secondary portion can be squeezed with a thumb and finger to allow access to the opening  218 . Pocket  216  may be of sufficient size to receive the entire volume of the transmitter unit  110  therein. The method  1100  may further include coupling the transmitter unit  110  to an electrical connector  234  provided in the pocket  216 . The electrical connector  234  may be a pogo-type electrical connector or other suitable connector. According to the method  1100 , the opening  218  of the secondary portion  101 S may be sealed. In some embodiments, the sealing comprises removing a backing member  225  to expose adhesive  220  applied on edges  222  of the opening  218  (See  FIGS. 5  and  FIGS. 2D-2F ). Slight pressure to the edges  222  can seal the opening  218  and hermetically seal the transmitter unit  110  into the pocket  216 . After separation of the wearable device  101  from the biosensor inserter  100  as shown in  FIG. 8 , the secondary portion  101 S can be unfolded and adhered to the skin as shown in  FIG. 9 . After separation of the biosensor inserter  100  from the wearable device  101 , the biosensor inserter  100  can be disposed of as medical waste, whereas the cover  105 . 
     The foregoing description discloses only example embodiments. Modifications of the above-disclosed apparatus and methods, which fall within the scope of this disclosure, will be readily apparent to those of ordinary skill in the art.