Invasive biosensor alignment and retention

Abstract

Examples of invasive biosensor alignment and retention features and methods are described. An exemplary biosensor includes: a housing including a first surface defining a first opening, and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor wire partially disposed within the housing and having an outer portion extending through the first opening; a hollow insertion needle positioned within the channel and extending through the first opening, the hollow insertion needle at least partially surrounding the biosensor wire; and a biosensor retention feature that surrounds and contacts the hollow insertion needle.

Description

[0001] This application is a divisional application of the Chinese patent application entitled “Invasive Biosensor Alignment and Retention” filed on July 31, 2018, with application number 201880059436.4. Technical Field

[0002] The present application relates generally to invasive biosensors, and more generally to alignment and retention of invasive biosensors. Background Art

[0003] Wearable, invasive biosensors, such as continuous glucose monitors (“CGMs”), employ sensor wires that are inserted into the wearer’s skin to measure an analyte, such as glucose levels. Because the sensor wires are typically small in diameter and may not be able to penetrate the wearer’s skin without bending or breaking, a needle is used to create a puncture wound through which the sensor wire is inserted. In some cases, the needle is inserted through an opening in the biosensor and axially aligned with the sensor wire, such that when the CGM is pressed against the wearer’s skin, the needle creates the puncture wound and inserts the sensor wire through the puncture. The needle is then withdrawn, leaving the sensor wire in place. Summary of the Invention

[0004] Various examples for aligning and retaining an invasive biosensor are described. An exemplary wearable biosensor includes a housing comprising a first surface defining a first opening and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor lead partially disposed within the housing and having an exterior portion extending through the first opening; a hollow insertion needle positioned within the passage and extending through the first opening, the hollow insertion needle at least partially surrounding the biosensor lead; and a biosensor retention feature surrounding and contacting the hollow insertion needle.

[0005] An exemplary method for providing alignment and retention of an invasive biosensor comprises: providing a housing comprising: a first surface defining a first opening, and a second surface opposite the first surface, the first surface defining a second opening, the first opening and the second opening defining a substantially unobstructed channel through the housing; positioning a biosensor wire within the housing with a first portion of the biosensor wire extending through the first opening; inserting a hollow insertion needle from the second opening into the channel, through the unobstructed channel and through the first opening, the hollow insertion needle at least partially surrounding the first portion of the biosensor wire; applying a biosensor retention feature to the hollow insertion needle, the biosensor retention feature surrounding and contacting the hollow insertion needle and being configured to collapse against a bottom surface of the housing.

[0006] Another exemplary wearable biosensor comprises: a housing comprising: a first surface defining a first opening, and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor lead partially disposed within the housing and having an outer portion extending through the first opening; a hollow insertion needle positioned within the passage and extending through the first opening coaxially aligned with the outer portion of the biosensor, the hollow insertion needle at least partially surrounding the outer portion of the biosensor lead; and a device for maintaining coaxial alignment between the hollow insertion needle and the biosensor lead, the biosensor lead being coupled to a portion of the hollow insertion needle coaxially aligned with the outer portion of the biosensor lead.

[0007] An exemplary method for applying a wearable biosensor comprises: obtaining a wearable biosensor, the wearable biosensor comprising: a housing, the housing comprising a first surface defining a first opening, and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor lead, partially disposed within the housing and having an outer portion extending through the first opening; a hollow insertion needle, positioned within the passage and extending through the first opening, the hollow insertion needle at least partially surrounding the biosensor lead; and a biosensor retention feature, collapsible against the first surface of the housing, the biosensor retention feature surrounding and contacting the hollow insertion needle; applying the wearable biosensor to a wearer's skin comprises: inserting the hollow insertion needle into the wearer's skin through a puncture, inserting the biosensor lead through the puncture, and pressing the housing against the wearer's skin and collapsing the biosensor retention feature against the housing; and withdrawing the hollow insertion needle from the wearer's skin and the housing.

[0008] These illustrative examples are not mentioned to limit or define the scope of the present disclosure, but to provide examples to aid understanding thereof. Illustrative examples are discussed in the detailed description, which provides further description. By examining this specification, the advantages provided by the various examples can be further understood. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more specific examples and, together with the description of the examples, serve to explain the principles and implementation of specific examples.

[0010] Figures 1A to 1E An exemplary invasive biosensor is shown along with an insertion needle and retention features;

[0011] Figures 2A to 2B shows exemplary biosensor alignment and retention features according to the present disclosure;

[0012] Figure 3 shows exemplary biosensor alignment and retention features according to the present disclosure;

[0013] Figures 4A to 4B shows exemplary biosensor alignment and retention features according to the present disclosure;

[0014] Figures 5A to 5B shows exemplary biosensor alignment and retention features according to the present disclosure;

[0015] Figures 6 to 7 shows an exemplary fabrication technique for aligning a biosensor and inserting a needle according to the present disclosure;

[0016] Figures 8A to 8B An exemplary method for assembling biosensor alignment and retention features is shown;

[0017] Figures 9A to 9B An exemplary method for assembling biosensor alignment and retention features is shown;

[0018] Figures 10A to 10B An exemplary method for assembling biosensor alignment and retention features is shown;

[0019] Figures 11A to 11B Exemplary biosensor alignment and retention features are shown;

[0020] Figures 12A to 12B Exemplary biosensor alignment and retention features are shown;

[0021] Figures 13A to 13B Exemplary biosensor alignment and retention features are shown;

[0022] Figures 14A to 14C Exemplary biosensor alignment and retention features are shown;

[0023] Figure 15 An exemplary method for assembling biosensor alignment and retention features is shown; and

[0024] Figure 16 An exemplary method for applying a wearable biosensor with biosensor alignment and retention features is shown. DETAILED DESCRIPTION

[0025] Examples are described herein in the context of invasive biosensor alignment and retention. Those skilled in the art will recognize that the following description is illustrative only and is not intended to be limiting in any way. Reference will now be made in detail to embodiments of the examples illustrated in the accompanying drawings. The same reference numerals will be used throughout the drawings and the following description to refer to the same or similar items.

[0026] For the sake of clarity, not all of the conventional features of the examples described herein are shown and described. Of course, it will be appreciated that in developing any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as meeting application- and business-related constraints, and that these specific goals will vary from implementation to implementation and from developer to developer.

[0027] Invasive biosensors include one or more sensing components that are inserted into the human body, such as through the person's skin, and can measure an analyte to determine information such as glucose levels. For example, a continuous glucose monitor ("CGM") can be applied to a person ("wearer") and worn by the wearer for a period of time to monitor the wearer's glucose levels. This exemplary CGM includes a sensor wire that is inserted into the wearer's skin to enter the interstitial fluid and sense glucose levels. However, because the sensor wire is fragile at the expected thickness / diameter (100 microns (or μm) in this example), a needle is used to pierce the skin and insert the sensor wire. The exemplary CGM is connected to the insertion device via a hollow insertion needle that is coaxially positioned with the CGM sensor wire located within the hollow portion of the insertion needle. When the wearer uses the CGM, she will pierce the skin with the insertion needle, and the sensor wire will follow the needle into the puncture. After the CGM sensor lead has been inserted into the puncture and the CGM attached to the wearer's skin, the wearer withdraws the needle, leaving the sensor lead beneath the skin and the CGM in place.

[0028] Reference Figures 1A to 1D , these figures show different views of an exemplary CGM 100 having a housing 110 and sensor wires 120. Figure 1A As can be seen in FIG, the sensor wire 120 extends out of the housing 110 so that it can be inserted into the wearer's skin, and the housing 110 can be attached to the wearer's skin.

[0029] To use the CGM 100, Figure 1BAs shown, a needle 130 (also referred to as an "insertion needle") is inserted through a hole in the upper surface of the CGM 100, through a cavity formed within the CGM 100 to accommodate the needle 130 and sensor lead 120, and through a hole in the lower surface of the CGM 100. The needle 130 is inserted so that it is axially aligned with the sensor lead 120. Thus, the CGM 100, needle 130, and sensor lead 120 can all be pressed against the wearer's skin, applying the CGM 100 in a single motion. When the CGM 100 is pressed against the wearer's skin, the needle 130 punctures the skin and the sensor lead 120 is pressed through the puncture. The CGM 100 is then pressed against the wearer's skin, where it is retained there by, for example, a pressure-sensitive adhesive ("PSA"). The needle 130 is then withdrawn, leaving the CGM 100 and sensor lead 120 in place.

[0030] Figures 1C to 1D FIG2 shows how the needle 130 and sensor wire 120 are joined to allow for substantially simultaneous insertion into the wearer's skin. In this example, the insertion needle 130 is hollow and has a Figure 1D The open cross-section shown may be described as having a "C" or "U" shape and extends slightly beyond the end of the sensor wire 120. The amount by which the needle extends beyond the sensor wire is not critical; however, piercing the wearer's skin beyond the depth required to insert the sensor wire 120 should be avoided as this may cause unnecessary pain or trauma to the wearer. Figure 1D As can be seen in FIG, the diameter of the needle's cross section is greater than the diameter of the sensor wire 120. By orienting and positioning the needle 130 to enclose the sensor wire 120 within its hollow cross section, the needle 130 and the sensor wire 120 can be coaxially positioned so that when the wearer presses the needle 130 into the wearer's skin to create a puncture, the sensor wire 120 can immediately travel into the puncture created by the needle 130.

[0031] However, in some examples, the CGM 100 may be packaged with the insertion needle 130 already coupled to the CGM 100. Thus, a user may obtain a new CGM 100 without having to insert the needle through the CGM 100 to apply the CGM 100 thereto. However, because the packaged CGM 100 may be subjected to various forces during manufacturing, packaging, and shipping, the sensor wire 120 and the needle 130 may become misaligned. For example, the sensor wire 120 may be jolted or bent out of the C-shaped cross-section, such as after the package is dropped. To help maintain the coaxial arrangement of the needle 130 and the sensor wire 120 while the sensor wire 120 is inserted subcutaneously, the CGM 100 has sensor alignment and retention features coupled to its bottom surface.

[0032] Now refer to Figure 1E , Figure 1E The bottom surface of a CGM 100 is illustrated with an attached sensor alignment and retention feature 140 (or "retention feature"). In this example, the retention feature 140 comprises a portion adhered to the bottom surface of the CGM 100, such as by a PSA. Additionally, the retention feature has an extendable portion 142 that has been cut and spiraled upward around the insertion needle 130. During manufacturing, the extendable portion 142 has been pulled away from the bottom surface of the CGM 100 to form a spiral shape. The tip of the cut portion 142 contains a tight-fitting hole that surrounds and engages the needle 130, helping to prevent the sensor wire 120 from falling out of the cross-section of the hollow insertion needle 130. When the CGM 100 is later applied to the wearer's skin, the extendable portion 142 collapses against the bottom surface of the CGM 100 as it is pressed against the wearer's skin and returns to a flat shape, ultimately resting flush against the bottom surface of the CGM 100. Thus, the extendable portion 142 helps maintain coaxial alignment between the sensor lead 120 and the insertion needle 130 while not interfering with the CGM insertion process.

[0033] This illustrative example is given to introduce the reader to the general subject matter discussed herein, and the present disclosure is not limited to this example.The following sections describe various other non-limiting examples and examples of systems and methods for invasive biosensor alignment and retention. Figures 2A to 14B Additional examples of devices for maintaining coaxial alignment between a hollow insertion needle and a biosensor lead are illustrated and described in more detail below.

[0034] Now refer to Figures 2A to 2B , Figures 2A to 2B An exemplary sensor alignment and retention feature 210 according to the present disclosure is shown. In this example, the retention feature 210 includes a pad (or backing material) 220 that can be used to couple the retention feature 210 to a biosensor, such as a CGM. The pad 220 can be formed during manufacturing to correspond to the shape of the lower surface of the biosensor or to correspond to a portion of the shape. The retention feature 210 also includes an expandable portion 230 that can be extended during manufacturing or when an insertion needle is inserted through the CGM to form a spiral feature to maintain coaxial alignment between the sensor wire and the insertion needle. Figure 2A In FIG. 2 , the expandable portion has not yet been extended and therefore remains flush with the liner 220. This helps illustrate the shape of the cut used to form the cut portion 230 and enables the cut portion to be extended to form a spiral shape.

[0035] In this example and during the manufacturing process, the liner 220 is formed from polyurethane foam, but may also be constructed from other materials, such as cloth, silicone, etc. In this example, the expandable portion 230 is formed from a different piece of material than the liner 220 and is coupled to the liner via an adhesive. However, in some examples, the expandable portion 230 may be formed from the same piece of material as the liner 220. In some examples, as will be discussed below with respect to Figure 6 As discussed in more detail in Figures 10 and 11, the padding may be formed of multiple layers coupled to one another. The expandable portion 230 may be formed of any suitable material, including polyurethane foam, silicone, etc. Furthermore, in some examples, the retention feature may not include the padding 220, but may instead include only the cutting portion 230.

[0036] Figure 2B The illustration shows a retention feature 210 attached to the bottom surface of an invasive biosensor 200. It can be seen that, while the gasket 220 does not cover the entire bottom portion in this example, it generally corresponds to the shape of the bottom surface of the biosensor 200. It should be understood that the gasket 220 can have any suitable size and shape depending on the application. For example, during the manufacturing process, the shape and size of the gasket 220 can be set to match the shape and size of the bottom surface of the biosensor 200. In some examples, the gasket 220 can extend beyond one or more edges of the bottom surface of the biosensor 200, or can only cover a portion of the bottom surface of the biosensor 200.

[0037] Now refer to Figure 3 , Figure 3 An exemplary sensor alignment and retention feature 310 (or simply "retention feature") according to the present disclosure is shown. In this example, the retention feature 310 comprises an "accordion pleat" shape. During the manufacturing process, a length of material has been folded upon itself multiple times, and a hole having a diameter tens of microns wider than the needle has been cut through the material to engage with and surround the insertion needle 320. In this example, by engaging and surrounding the insertion needle 320, the sensor wire positioned within the hollow portion of the needle can be retained. If an impact or force is applied to the sensor wire, it can be retained in place within the hollow portion of the needle by the retention feature. Furthermore, when the biosensor 300 is applied to a wearer, the retention feature 310 can fold and collapse against the bottom surface of the biosensor 300.

[0038] although Figure 3 The example shown does not include a liner as described above. Figures 2A to 2B As discussed above, however, in some examples, the retention feature may also include or be coupled to the pad. Figures 2A to 2BAs discussed with respect to the examples of , any suitable liner may be employed. Additionally, the retention feature 310 may be constructed separately and subsequently coupled to the liner, or may be formed from the same piece of material as the liner.

[0039] Now refer to Figures 4A to 4B , Figures 4A to 4B An exemplary sensor alignment and retention feature 420 (or just "retention feature") according to the present disclosure is shown. In this example, the retention feature 420 is coupled to a pad 410 that can be attached to a device such as a Figure 4B The lower surface of the biosensor of the biosensor 400 is shown in FIG. In this example, the retaining feature 420 has a central feature 424 that engages and surrounds the insertion needle 430 of the biosensor 400. Figure 4A In the example shown, the central feature 424 does not yet have an opening, such as a hole or slit (e.g., in the shape of a "|," "X," or "*"), cut therein for accommodating the insertion needle 430; however, the opening may be cut at any suitable time during the manufacturing process, or it may be formed when the insertion needle is inserted through the CGM and retention features, which may occur during the manufacturing process or when the CGM is applied by the wearer.

[0040] In addition to central feature 424, exemplary retention feature 420 includes two legs 422a-b. Each leg 422a-b has two ends, one of which is coupled to pad 410, or, if a pad is not used, a ring or other feature can be attached to the bottom surface of biosensor 400. The other end of each leg 422a-b is coupled to central feature 424. In this example, legs 422a-b are attached to opposite sides of central feature 424 and then each couple to a corresponding point on pad 410 approximately 180 degrees around central feature 424, i.e., offset 180 degrees from each other. In different examples, the legs can couple to different locations on pad 410 relative to the coupling point on central feature 424, such as at a 90-degree offset, a 120-degree offset, etc. Furthermore, while two legs 422a-b are shown in this example, in some examples, more than two legs can be used. The two legs 422a-b allow the central feature 424 to extend away from the biosensor to engage and surround the insertion needle 430 at a location between the bottom surface of the biosensor 400 and the tip of the needle 430, as shown. Figure 4B Additionally, the legs 422a-b allow the central feature 420 to collapse against its bottom surface when the biosensor 400 is applied to the wearer's skin.

[0041] Now refer to Figures 5A to 5B , Figures 5A to 5BAn exemplary sensor alignment and retention feature 520 (or just "retention feature") according to the present disclosure is shown. In this example, the retention feature 520 is coupled to a gasket 510, which may be attached during manufacture to a substrate such as a Figure 5B The lower surface of the biosensor 500 is shown in FIG. Figure 4A In the example shown, the retention feature 520 has a central feature 524 that engages and surrounds the insertion needle 530 of the biosensor 500. Figure 5A In the example shown, central feature 524 does not yet have an opening cut therein for accommodating insertion needle 530; however, the opening may be cut at any suitable time during the manufacturing process. Alternatively, in some examples, the opening may be formed when the insertion needle is inserted through the CGM and retention feature, which may occur during the manufacturing process or when the CGM is applied by the wearer.

[0042] In addition to the central feature 524, the exemplary retention feature 520 includes two legs 522a-b. Figure 4A In the example shown in FIG, each leg 522a-b has two ends, one of which is coupled to the pad 510, or if a pad is not used, a ring or other feature can be attached to the bottom surface of the biosensor 500. The other end of each leg 522a-b is coupled to the central feature 524. In this example, the legs 522a-b are attached at opposite sides of the central feature 524 and then each is coupled to a corresponding point on the pad 510 that is offset approximately 90 degrees around the central feature 524. As described above with respect to Figure 4A and 4B As discussed, any suitable number of legs may be employed in various embodiments. For example, Figure 5A The retaining feature 520 shown in can be modified to add two additional legs, each of which can be connected to the center feature 524 so that each leg is connected at a position offset 90 degrees from each other, and the other end of each leg is also connected at a position offset 90 degrees from each other on the liner 510.

[0043] In this example, the two legs 522a-b allow the central feature 524 to extend away from the biosensor 500 to engage and surround the insertion needle 530 at a location between the bottom surface of the biosensor 500 and the tip of the needle 530, as shown. Figure 5B . Additionally, the legs 522a-b allow the central feature 520 to collapse against its bottom surface when the biosensor 500 is applied to the wearer's skin. Thus, this exemplary retention feature 520 is capable of aligning and retaining the sensor wire within the hollow insertion needle 530 used to apply the invasive biosensor 500.

[0044] Now refer to Figure 6 , Figure 6 An exploded view of an exemplary gasket and sensor alignment and retention assembly 600 is shown. The exemplary alignment and retention assembly 600 comprises four components that can be manufactured and assembled separately to provide sensor alignment and retention for an invasive biosensor. The assembly 600 comprises a retention feature 610, a top adhesive layer 620, a backing material 630, and a bottom adhesive layer 640. In this example, the retention feature 610 has a Figures 5A to 5B , which has two legs and a central feature. In this example, retaining feature 610 is manufactured separately from a piece of polyurethane foam by cutting away portions of the foam to form the legs, central feature, and peripheral ring.

[0045] The top layer adhesive 620 is a PSA that is applied to the backing material 630 during the manufacturing process. The PSA is applied to the perimeter of the retention features 610 and is also applied to portions of the backing material 630 to provide adhesion between the backing material 630 and the bottom surface of the biosensor housing. In this example, the top layer adhesive 620 is provided as a single piece of double-sided tape, but in some examples it can be sprayed onto the backing material 630 or can include multiple pieces of tape. In addition, the top layer adhesive 620 can be applied to any suitable location on the backing material 630 to provide adhesion between the backing material 630 and the retention features 610, as well as between the backing material 630 and the bottom surface of the biosensor housing.

[0046] In this example, the backing material 630 is comprised of a polyurethane-coated fabric; however, any suitable material may be used, such as cloth, foam, etc. In this example, the backing material 630 is cut from a sheet of material into a shape corresponding to the shape of the biosensor housing and having holes corresponding to the retaining features.

[0047] The bottom adhesive 640 is a PSA that is applied to the backing material 630 and is intended to adhere the backing material 630, and thereby the invasive biosensor, to the wearer's skin. Thus, the bottom adhesive 640 comprises an adhesive suitable for long-term contact with human skin. This adhesive can be water- and moisture-resistant. In this example, the adhesive comprises double-sided tape that has been cut into a shape corresponding to the shape of the backing material 630. In some examples, the bottom adhesive 640 can comprise another type of adhesive, such as a liquid that can be sprayed onto the backing material 630 or can comprise multiple pieces of tape.

[0048] To create Figure 6In the exemplary assembly 600 shown in , a top layer of adhesive 620 is applied to one side of a backing material 630. Then, a retaining feature 610 is pressed against the backing material 630 at a position corresponding to the top layer of adhesive 620 and the hole formed in the backing material 630. Then, a bottom layer of adhesive 640 is applied to the other side of the backing material 630. It should be understood that the order of the above steps can vary according to different manufacturing processes. In some examples, other steps can be included, the above steps can be omitted, or the steps can be performed in a different order. For example, the backing material 630 having the top layer of adhesive 620 and the retaining feature 610 can be adhered to the bottom surface of the invasive biosensor before the bottom layer is applied. Further variations are also within the scope of the present disclosure.

[0049] Now refer to Figure 7 , Figure 7 Shown is an exploded view of an exemplary pad and sensor alignment and retention assembly 700. In this example, the assembly includes a backing material 720 having a top layer of adhesive 710 and a bottom layer of adhesive 730.

[0050] and Figure 6 Unlike the exemplary assembly 600 shown in FIG, in this example, the assembly has a retention feature 722 formed from the same sheet of material as the backing material 720. Thus, rather than having two separate sheets, the backing material and the retention feature are formed from the same sheet of material. A top layer of adhesive 710 can then be applied to one side of the backing material 720 to adhere the backing material to the bottom surface of the invasive biosensor. A bottom layer of adhesive 730 can be applied to the other side of the backing material 720 to adhere the backing material 720 to the wearer's skin. Suitable materials for the backing material 720 and the retention feature 722, as well as suitable adhesives for the top layer of adhesive 710 and the bottom layer of adhesive 730, are described above.

[0051] Now refer to Figures 8A to 8B , Figures 8A to 8B An exemplary technique 800 for applying a retention feature to an invasive biosensor is illustrated. In this example, a method similar to Figure 6 An exemplary backing material (or gasket) and sensor alignment and retention assembly 600 is shown, but any other suitable assembly according to the present disclosure may be used. Figures 8A to 8B The described technique 800 involves an assembly having different cushioning and retention features formed from different pieces of material.

[0052] exist Figure 8AAt block 810a of FIG. 8 , illustrated in corresponding diagram 810b , adhesive 852 is applied to biosensor housing 850 . In this example, top layer of adhesive 852 is a double-sided tape that is cut into a shape corresponding to the shape of the bottom surface of housing 850 and pressed against the bottom surface of housing 850 . However, in some examples, adhesive 852 can be sprayed onto the housing, housing 850 can be dipped into the adhesive, or any other suitable technique can be used to apply the adhesive to the bottom surface of housing 850 , such as using heat to fuse the components together. In this example, adhesive 852 is applied to the entire bottom surface of the housing; however, in some examples, adhesive 852 can be applied to locations corresponding to retention features 854 and to one or more other locations corresponding to pad 856 or pads.

[0053] At block 820a, illustrated in corresponding diagram 820b, retention features 854 are attached to the bottom surface of housing 850 by pressing them against adhesive 852. Retention features 854 are applied at locations corresponding to where the sensor wires and needle extend (or will extend) from the bottom surface of housing 850, such that the opening in retention feature 934 aligns with the exit point of the sensor wires from the bottom surface of housing 850.

[0054] At block 830a, illustrated in corresponding diagram 830b, a gasket 856 is attached to the bottom surface of housing 850 by pressing it against adhesive 852. In this example, retention features 854 are not separately adhered to gasket 856, but instead, gasket 856 has cutouts corresponding to the retention features, thereby allowing gasket 856 to adhere to housing 850 without interfering with the function of the retention features.

[0055] After the liner 856 is attached to the bottom surface of the housing 850, an adhesive may be applied to the exposed surface of the liner 856 to allow the liner 856 to adhere to the wearer's skin. This additional adhesive may be applied before or after the liner 856 is attached to the housing 850. Furthermore, this additional adhesive may be applied in the form of a tape or may be sprayed onto the liner 856.

[0056] It should be understood that the above Figure 8A The order of the steps described in method 800 may vary depending on the manufacturing process. In some examples, additional steps may be included, the aforementioned steps may be omitted, or the steps may be performed in a different order. For example, adhesive 852 may be applied to retention feature 854 and liner 856, respectively, which may be pressed against the bottom surface of housing 850. Further variations are also within the scope of the present disclosure.

[0057] Now refer to Figures 9A to 9B , Figures 9A to 9B An exemplary technique 900 for applying a retention feature to an invasive biosensor is illustrated. In this example, a method similar to Figure 6 An exemplary gasket and sensor alignment and retention assembly 600 is shown, but any other suitable assembly according to the present disclosure may be used. Figures 9A to 9B The described technique 900 involves an assembly having different cushioning and retention features formed from different pieces of material.

[0058] At block 910a, illustrated in corresponding diagram 910b, retention feature 934 is attached to the bottom surface of housing 930 by applying adhesive to a portion of retention feature 932 and pressing retention feature 934 against the housing. For example, referring again to Figure 6 930 , adhesive 932 can be applied to one side of the ring surrounding the legs and the central feature of the retention feature. Thus, retention feature 934 can be applied to the housing while allowing the legs and the central feature to extend away from the housing 930 and engage the insertion needle. After adhesive 932 has been applied to retention feature 934, it can be attached to the housing 930 by pressing it against the housing 930. Retention feature 934 is applied to the housing 930 at a location corresponding to where the sensor wires and needle extend (or will extend) from the bottom surface of the housing 930, so that the hole or slit in the retention feature 934 is aligned with the exit point of the sensor wires from the bottom surface of the housing 930.

[0059] At block 920a, illustrated in corresponding diagram 920b, liner 938 is attached to the bottom surface of housing 930 by applying adhesive 936 to one side of liner 938 and pressing it against the bottom surface of housing 930. In this example, liner 938 has cutouts corresponding to retention features 934, allowing the liner to adhere to housing 930 without interfering with the functionality of the retention features.

[0060] After the liner 938 is attached to the bottom surface of the housing 930, an adhesive may be applied to the exposed surface of the liner 938 to allow the liner 938 to adhere to the wearer's skin. This additional adhesive may be applied before or after the liner 938 is attached to the housing 930. Furthermore, this additional adhesive may be applied in the form of a tape or may be sprayed onto the liner 938.

[0061] It should be understood that the above Figure 9AThe order of the steps described in method 900 can vary depending on different manufacturing processes. In some examples, additional steps can be included, the above steps can be omitted, or the steps can be performed in a different order. For example, adhesive 932 can be applied to housing 930, and then retention features 944 can be adhered to housing 930. Similarly, adhesive 936 can be applied to housing 930, and then gasket 938 can be pressed against the bottom surface of housing 850. Further variations are also within the scope of the present disclosure.

[0062] Now refer to Figures 10A to 10B , Figures 10A to 10B An exemplary technique 1000 for applying a retention feature to an invasive biosensor is illustrated. In this example, a device similar to Figure 6 An exemplary gasket and sensor alignment and retention assembly 600 is shown, but any other suitable assembly according to the present disclosure may be used. Figures 10A to 10B The described technology 1000 involves an assembly having different cushioning and retention features formed from different pieces of material.

[0063] At block 1010a, a gasket 1034 is attached to the bottom surface of the housing 930. Adhesive 1032 may be applied to the housing 1030, or it may be applied to the gasket 1034. The gasket 1034 is then attached to the housing 1030 by pressing it against the bottom surface of the housing 1030.

[0064] At block 1020a, illustrated in corresponding diagrams 1020b and 1020c, retention features are applied to the biosensor. With respect to example 1020b, liner 1034 is shaped to correspond to the shape of housing 1030, although it has portions extending beyond the edges of housing 1030. Furthermore, while liner 1034 has openings cut therein to accommodate sensor wires and an insertion needle, the retention features are attached to liner 1034 rather than housing 1030. In this example, an adhesive is applied to the bottom surface of the liner, such as an adhesive suitable for adhering liner 1034 to the wearer's skin. Retention features 1036 are then pressed against the liner and attached via the adhesive.

[0065] With respect to example 1020c, the liner 1035 is shaped to correspond to the shape of the housing 1030, although it has portions that extend beyond the edges of the housing 1030. Additionally, the liner 1035 has a portion cut away therefrom to allow the retention feature 1036 to be attached directly to the housing 1030 via the adhesive 1032. The retention feature 1036 is inserted into a cutout in the liner 1034, pressed against the housing 1030, and attached via the adhesive 1032.

[0066] Retention features 1036 are applied to housing 1030 at locations corresponding to where the sensor wires and needle extend (or will extend) from the bottom surface of housing 1030, such that the opening in retention features 1036 is aligned with the exit point of the sensor wires from the bottom surface of housing 1030. Additionally, after liner 1034 is affixed to the bottom surface of housing 1030, an adhesive can be applied to the exposed surface of liner 1034 to allow liner 1034 to adhere to the wearer's skin. This additional adhesive can be applied before or after liner 1034 is affixed to housing 1030. Furthermore, this additional adhesive can be applied in the form of a tape or can be sprayed onto liner 1034.

[0067] Referring now to Figures 11a-11b, Figures 11a-b illustrate an exemplary sensor alignment and retention feature 1110. In this example, the retention feature 1110 is a disk of material having an opening cut therein to allow the insertion needle and sensor wire to be inserted through the retention feature 1110. Unlike the previous examples, in this example, the retention feature 1110 is not attached to the housing or liner, but is instead positioned along the length of the insertion needle 1120 between the base of the invasive sensor 1100 and the tip of the needle 1120 and is secured in place by a tight fit of the needle through the material. Thus, the retention feature 1110 engages with the needle 1120 and surrounds it, thereby maintaining the sensor wire within the hollow portion of the sensor wire. Although in this example, the retention feature 1110 has a circular shape, any suitable shape for a retention feature may be used.

[0068] Figure 11a illustrates a retention feature 1110 mounted on an insertion needle before the biosensor is attached to a wearer. Figure 11b illustrates how the retention feature 1110 collapses against the bottom surface of the biosensor 1100 after the biosensor has been attached to the wearer. This exemplary retention feature 1110 slides upward along the needle 1120 until it presses against the underside of the biosensor.

[0069] Reference is now made to Figures 12a-12b, which illustrate exemplary sensor alignment and retention features 1244. Shown in Figure 12a is a biosensor 1200 having a housing 1210 to which a gasket 1242 is adhered by adhesive 1240. A sensor lead 1230 extends through a cavity defined in the housing 1210 and downwardly through an aperture on the bottom surface of the housing 1210. Additionally, an insertion needle 1220 has been inserted through an aperture defined in the upper surface of the housing 1210, through a cavity defined between the apertures on the upper and lower surfaces of the housing 1210, and outwardly through the bottom of the biosensor 1200. As shown, a portion of the sensor 1230 is positioned within the hollow portion of the insertion needle 1220, such that the two are coaxially aligned.

[0070] In this example, the retaining feature 1244 is shown with Figures 11A to 11B 12. Specifically, retention feature 1244 engages insertion needle 1220 but is not otherwise attached to biosensor 1200. Instead, retention feature 1244 is positioned on the needle between pad 1242 and the tip of needle 1220 before biosensor 1200 is attached to the wearer.

[0071] FIG12 b illustrates biosensor 1200 after it has been applied to a wearer and insertion needle 1220 has been withdrawn. Retention feature 1244 has been forced upward into contact with liner 1242, and sensor lead 1230 has been retained in place within the wearer's skin. Because the underside of liner 1242 is coated with an adhesive for attachment to the skin, retention feature 1244 can adhere to the bottom of liner 1242. Therefore, at a later time, when biosensor 1200 is removed, retention feature 1244 will be removed along with biosensor 1200.

[0072] Reference is now made to Figures 13a-13b, which illustrate exemplary sensor alignment and retention features 1344. Shown in Figure 13a is a biosensor 1300 having a housing 1310 to which a gasket 1342 is adhered by adhesive 1340. A sensor lead 1330 extends through a cavity defined in the housing and downwardly through an aperture in the bottom surface of housing 1330. Additionally, an insertion needle 1320 has been inserted through an aperture defined in the upper surface of housing 1310, through a cavity defined between the apertures in the upper and lower surfaces of housing 1310, and outwardly through the bottom of biosensor 1300. As shown, a portion of sensor 1330 is positioned within the hollow portion of insertion needle 1320, such that the two are coaxially aligned.

[0073] This example is similar to Figures 12A to 12B The example shown, however, is as can be seen in the figure, Figures 13A to 13B The liner 1342 in the housing 1310 has a portion cut away to allow the retention feature to slide up against the housing and lie flush with the liner 1342. Thus, after the biosensor 1300 has been attached to the wearer's skin and the insertion needle 1320 has been removed, the retention feature 1344 has slid up into the cutout area in the liner 1342, making it flush with the liner 1342 and adhered to the housing 1310 via the adhesive 1340. Thus, at a later time, when the biosensor 1300 is removed, the retention feature 1344 will be removed along with the biosensor 1300.

[0074] Now refer to Figures 14A to 14C , Figures 14A to 14C An exemplary sensor alignment and retention feature 1430 according to the present disclosure is illustrated. In this example, an invasive biosensor 1400 includes a sensor wire 1410 extending from the bottom surface of the biosensor 1400. An insertion needle 1420 has been inserted through the biosensor and is coaxially aligned with the sensor wire 1410. In this example, the retention feature 1430 has a shape similar to a plug having an opening formed therethrough to accommodate the insertion needle 1430 and is constructed of a material such as silicone rubber or another elastomeric material.

[0075] The retention feature 1430 has a flat bottom surface 1432 that will be flush with the bottom surface of the biosensor 1400 once the biosensor 1400 has been attached to the wearer's skin. Figures 13A to 13B 1344, the retention feature 1410 is attached to a portion of the insertion needle by an interference fit, but is not otherwise attached to the biosensor 1400, as shown. Figures 14A to 14B When the biosensor 1400 is applied to the wearer's skin, the retention feature 1430 slides up along the needle 1420 and into the cavity 1402 defined in the underside of the biosensor 1400, thereby allowing the retention feature 1430 to collapse into the biosensor 1400 and be retained thereby, as shown in FIG. Figure 14C Visible in.

[0076] Now refer to Figure 15 , Figure 15 An exemplary method 1500 for aligning and retaining an invasive biosensor according to the present disclosure is shown. Figures 14A to 14B ; however, according to various examples, any suitable retaining feature or device according to the present disclosure may be employed.

[0077] At block 1510, a biosensor is obtained. In this example, the biosensor is obtained by constructing a biosensor. The biosensor is constructed by obtaining a housing having a first surface defining a first opening and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing.

[0078] After obtaining the housing, a biosensor lead is positioned within the housing and oriented such that a first portion of the biosensor lead extends through the first opening and out of the housing. A hollow insertion needle is then inserted from the second opening into the unobstructed passageway, through the passageway, and through the first opening, such that the hollow insertion needle at least partially surrounds the portion of the biosensor lead extending out of the housing.

[0079] At block 1520, retention features 1430 are obtained. For example, retention features 1430 may be received during a manufacturing process, such as by an automated machine operating as part of an assembly line. In one example, retention features 1430 are picked up by a robotic arm. In some examples, retention features 1430 may be provided in an uncut sheet of material having one or more pre-formed retention features 1430.

[0080] At block 1520, the retention feature 1430 is attached to the needle 1420 of the biosensor 1400. In this example, and as described above, the needle 1420 is inserted through the housing of the biosensor 1430, such as through a hole on the upper surface of the biosensor 1400, through a cavity formed within the biosensor 1420, and out through a hole on the lower surface of the biosensor 1400. Furthermore, the needle 1420 is coaxially aligned with the sensor wire 1410, which is mounted within the biosensor but extends downwardly through a hole on the bottom surface of the biosensor 1400 and is positioned within the hollow portion of the needle 1420.

[0081] In this example, the opening formed in the retention feature 1430 is aligned with the needle 1420, and the retention feature 1430 is pressed onto the needle 1420 and slides along a portion of the length of the needle 1420. The distance that the retention feature 1430 slides along the length of the needle 1420 can vary according to different examples, however, in this example, the retention feature 1430 is ultimately positioned to allow approximately 1 to 5 mm of the needle 1420 (including the sharp tip of the needle 1420) to protrude from the retention feature 1430. In some examples, the retention feature 1430 can be positioned so that no portion of the needle 1420 protrudes from the retention feature 1430, but the sharp tip of the needle 1420 is generally aligned with the flat bottom surface 1432 of the retention feature 1430. Such positioning can provide sensor alignment and retention functions, and can also shield the end of the needle 1420 to prevent it from accidentally contacting the wearer or some other object before being inserted into the wearer's skin.

[0082] In this example, needle 1420 is pressed through a hole formed on retention feature 1430; however, in some examples, a retention feature may be formed without such a hole. Thus, the needle may be pressed through the retention feature to form a hole and couple the retention feature to the needle.

[0083] In some examples, at block 1520, the retain feature 1430 may be applied, as described above with respect to Figures 8A to 8B 、 Figures 9A to 9B or Figures 10A to 10B Other components as described, such as one or more adhesives or gaskets.

[0084] In some examples, such as Figures 11A to 11B 、 Figures 12A to 12B or Figures 13A to 13B In the example shown in , the retaining feature 1430 discussed above can be replaced with a disc, such as Figures 11A to 11B In addition, the disk 1110 shown in FIG. Figures 8A to 8B 、 Figures 9A to 9B or Figures 10A to 10B As discussed in methods 800 to 1000, applying one or more liners or adhesives, such as Figures 12A to 12B and Figures 13A to 13B As shown in .

[0085] Now refer to Figure 16 , Figure 16 A method 1600 for applying a wearable biosensor with a biosensor retention feature is shown. Figure 16 The exemplary method will be about Figures 11A to 11B ; however, any suitable wearable biosensor and biosensor retention features according to the present disclosure may be employed.

[0086] At box 1610, the wearer obtains a wearable biosensor 1100 having a biosensor retention feature 1110 that surrounds and contacts a hollow insertion needle that is inserted through the biosensor housing and coaxially aligned with a portion of a sensor wire extending from the biosensor housing.

[0087] At block 1620, the wearer applies the wearable biosensor 1100 by inserting the hollow insertion needle 1120 into the wearer's skin through a puncture at a desired location on the wearer's skin. The wearer also inserts the biosensor lead through the puncture by pressing the housing of the wearable biosensor against the wearer's skin, collapsing the biosensor securing member against the housing, taking advantage of the coaxial alignment between the biosensor lead and the hollow insertion needle 1120.

[0088] At block 1630, the wearer withdraws the insertion needle from the puncture and housing, attaching the wearable biosensor to the wearer's skin, and the biosensor lead is inserted through the patient's skin.

[0089] The above description of some examples is given for the purpose of illustration and description only, and is not intended to be exhaustive or to limit the present disclosure to the precise form disclosed. Many modifications and adaptations thereof will be apparent to those skilled in the art without departing from the spirit and scope of the present disclosure.

[0090] References herein to examples or embodiments mean that a particular feature, structure, operation, or other characteristic described in conjunction with the example may be included in at least one embodiment of the present disclosure. The present disclosure is not limited to the particular examples or embodiments described herein. The appearance of the phrases "in one example," "in an example," "in one embodiment," or "in an embodiment," or variations thereof in various places in the specification, do not necessarily refer to the same example or embodiment. Any particular feature, structure, operation, or other characteristic described in this specification with respect to one example or embodiment may be combined with other features, structures, operations, or other characteristics described with respect to any other example or embodiment.

[0091] As used herein, the word "or" is intended to encompass both inclusive and exclusive OR conditions. In other words, A or B or C includes any or all of the following alternative combinations as appropriate for a particular purpose: A only; B only, C only; A and B only; A and C only; B and C only; and A, B, and C.

Claims

1. A wearable biosensor comprising: A housing comprising: a first surface defining a first opening, and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor lead partially disposed within the housing and having an outer portion extending through the first opening; a hollow insertion needle positioned within the passageway and extending through the first opening, the hollow insertion needle at least partially surrounding the biosensor wire; and A biosensor retention feature surrounds and contacts the hollow insertion needle.

2. The wearable biosensor of claim 1 , wherein the biosensor retention feature comprises a patch, an inner ring member, an outer ring member, and at least one flexible leg member coupling the inner ring member to the outer ring member, The inner ring member surrounds and contacts the hollow insertion needle, The outer ring member is attached to the patch, and The patch is attached to the bottom surface of the shell.

3. The wearable biosensor of claim 2 , wherein the biosensor retention feature comprises a plurality of flexible leg members coupling the inner ring member to the outer ring member, each of the flexible leg members being attached to the inner ring member at a respective first contact point and to the outer ring member at a respective second contact point.

4. The wearable biosensor of claim 3, wherein the respective first and second contact points for at least one flexible leg member are offset from one another.

5. The wearable biosensor of claim 1 , wherein the biosensor retention feature comprises a disk defining an aperture, the insertion needle and the biosensor wire extending through the aperture on the disk, the disk being spaced apart from the bottom surface of the housing.

6. The wearable biosensor of claim 5, wherein the biosensor retaining feature comprises a flexible material. 7 . The wearable biosensor according to claim 4 , wherein the flexible material comprises a polyurethane foam material or a silicone material.

8. The wearable biosensor of claim 5, wherein the biosensor retention feature is adapted to cause the disc to slide along the hollow insertion needle and into contact with the bottom surface of the housing in response to a force applied to the bottom surface of the disc.

9. The wearable biosensor of claim 1 , wherein the biosensor retaining feature comprises a plug-shaped member defining a hole extending therethrough, the insertion needle and the biosensor wire extending through the hole in the plug-shaped member.

10. The wearable biosensor according to claim 9, wherein the plug-shaped member is configured to slide along the hollow insertion needle and into the opening defined on the bottom surface of the housing in response to a force applied to the bottom surface of the plug-shaped member.

11. The wearable biosensor of claim 1 , further comprising a pad affixed to the bottom surface of the housing, the retention feature coupled to and extending away from the pad.

12. The wearable biosensor according to claim 1 further comprises a pad attached to the bottom surface of the shell, the retaining feature is not connected to the pad, the pad defines a cutout portion corresponding to the retaining feature, and the retaining feature is configured to collapse against the shell and enter the cutout portion defined by the pad.

13. A wearable biosensor comprising: A housing comprising: a first surface defining a first opening, and a second surface opposite the first surface, the second surface defining a second opening, the first opening and the second opening defining a substantially unobstructed passage through the housing; a biosensor lead partially disposed within the housing and having an outer portion extending through the first opening; a hollow insertion needle positioned within the passageway and extending through the first opening coaxially aligned with the outer portion of the biosensor, the hollow insertion needle at least partially surrounding the outer portion of the biosensor lead; and Means for maintaining coaxial alignment between the hollow insertion needle and the biosensor lead, the biosensor lead coupled to a portion of the hollow insertion needle coaxially aligned with the outer portion of the biosensor lead.

14. The wearable biosensor of claim 13, wherein the means for maintaining coaxial alignment comprises at least one flexible leg.

15. The wearable biosensor of claim 13, wherein the means for maintaining coaxial alignment is spaced apart from the housing.

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