Continuous multianalyte sensor system.

Abstract

Various embodiments disclosed relate to analyte sensor configurations. The disclosure may include planar analyte sensors or coaxial analyte sensors. Planar analyte sensors may include one or more insulating and conductive layers layered together and a substrate. Coaxial analyte sensors may include one or more co-extruded wire electrodes with a substrate. Continuous analyte monitoring systems discussed herein may be configured to monitor one or more analytes to provide predictive and real-time health data and benefits.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. patent application Ser. No. 63 / 321,538, entitled "CONTINUOUS ANALYTE SENSOR SYSTEMS," filed March 18, 2022, which claims priority to U.S. patent application Ser. No. 63 / 403,568, entitled "CONTINUOUS MULTI-ANALYTE SENSOR DEVICES AND METHODS," filed September 2, 2022, which claims priority to U.S. patent application Ser. No. 63 / 403,582, entitled "DEVICES AND METHODS FOR MEASURING AN ELECTROPHYSIOLOGICAL SIGNAL AND / OR A CONCENTRATION OF A TARGET ANALYTE IN A BIOLOGICAL FLUID IN VIVO," filed March 16, 2023. This application claims priority to U.S. patent application Ser. No. 63 / 490,589, entitled "METHOD FOR INTERFACE SYSTEMS," all of which are incorporated herein by reference in their entireties.

[0002] FIELD OF THEINVENTION The present development relates generally to medical devices such as analyte sensors, and more particularly, but not exclusively, to architectures and manufacturing techniques for analyte sensors. [Background technology]

[0003] A variety of systems can be used to monitor one or more analyte levels in a subject or subjects. These levels can be monitored and analyzed to determine various aspects of the subject's current health, as well as to predict future states of health, including the occurrence and monitoring of conditions such as metabolic states. Thus, there is a need for improved analyte monitoring systems that can safely, reliably, and effectively provide accurate monitoring of analyte levels in a subject.

[0004] This Background is provided to introduce a brief background to the Summary and Detailed Description that follow. This Background is not intended to aid in determining the scope of the claimed subject matter, nor should it be deemed to limit the claimed subject matter to implementations that solve any or all of the disadvantages or problems presented above. Summary of the Invention

[0005] The present disclosure provides various architectures and methods for manufacturing and using analyte sensors, such as continuous glucose sensors, useful for diabetic patients. The analyte sensors can be used, for example, to monitor blood glucose levels in diabetic patients. As discussed herein, such analyte sensor architectures can include planar and coaxial structures.

[0006] In an embodiment, the analyte sensor may include a substrate extending between a proximal portion and a distal portion, a first electrode, a second electrode, and an insulating layer between the first and second electrodes. The substrate may be planar. The first electrode may be a working electrode. The first electrode and the second electrode may each be substantially parallel to the substrate, and the first electrode and the second electrode may each be planar. The insulating layer may be planar. The first electrode may extend further toward the distal portion of the substrate than the second electrode.

[0007] In an embodiment, the analyte sensor may include a substrate extending between a proximal portion and a distal portion, a first electrode extending along the substrate between the proximal portion and the distal portion, a second electrode extending along the substrate between the proximal portion and the distal portion, and an insulating portion electrically isolating the first and second electrodes. The substrate may include a cylindrical member having a central axis surrounded by a plurality of concentric circles of increasing radius. The concentric circles may be visible through a cross section of the substrate. The first electrode may be a working electrode. The first and second electrodes may each be aligned with one of the plurality of concentric circles, and the first electrode may extend further toward the distal portion of the substrate than the second electrode.

[0008] In embodiments, a method of fabricating an analyte sensor can include aligning one or more insulating layers and one or more conductive layers in an alternating manner, layering the one or more insulating layers and the one or more conductive layers together, and selectively removing portions of the one or more insulating layers to expose at least two electrodes.

[0009] In an embodiment, a method of fabricating an analyte sensor may include co-extruding at least two electrode wires into a cylindrical shape to produce a substrate and an analyte sensor, where each of the at least two electrodes are aligned with a different concentric circle within the cylindrical shape; singulating the produced analyte sensor into a plurality of individual analyte sensors; and selectively removing a predetermined portion of the substrate material on each of the individual analyte sensors to expose a sensing region of the at least two electrodes.

[0010] In examples, the continuous analyte sensor can include a substrate having a first side and a second side opposite the first side, the substrate being planar; a first working electrode on the substrate; a second working electrode on the substrate; a reference electrode on the substrate, the first working electrode, the second working electrode, and the reference electrode each being a planar electrode, at least two of the first working electrode, the second working electrode, or the reference electrode being on the first side of the substrate and any remaining planar electrodes being on the second side of the substrate, and at least two of the first working electrode, the second working electrode, and the reference electrode being coplanar with one another; and an interconnect extending through the substrate between the first side and the second side, the interconnect in electrical communication with one of the reference electrode, the first working electrode, or the second working electrode.

[0011] In an embodiment, the sensor may include a substrate having a first side and a second side opposite the first side, the substrate being planar; a first sensor system on the substrate, the first sensor system being a continuous analyte sensor configured to collect a first type of measurement, the first sensor system comprising a working electrode, a reference electrode on the substrate, the working electrode and the reference electrode each being a planar electrode, and at least one analyte sensing membrane extending over the at least one working electrode; and a second sensor system on the substrate, the second sensor system being configured to collect a second type of measurement different from the first type of measurement.

[0012] In an embodiment, a continuous analyte sensor may include: a planar substrate having a distal portion and a proximal portion connected by a junction, the distal portion and the proximal portion being connected via the junction at an angle between 70 and 110 degrees; a first electrode on the distal portion of the substrate and a first connection pad on the proximal portion, the first electrode and the first connection pad being electrically coupled through a first trace routed through the junction; a second electrode on the distal portion of the substrate and a second connection pad on the proximal portion, the second electrode and the second connection pad being electrically coupled through a second trace routed through the junction; and at least one analyte sensing membrane extending over one or more of the first and second electrodes.

[0013] In an embodiment, a method of fabricating a planar analyte sensor may include layering a first insulating material, a first conductive material, and a second conductive material on a first side of a substrate; selectively removing portions of the first insulating material to expose portions of the first conductive material to form a first electrode; selectively removing portions of the first insulating material to expose portions of the second conductive material to form a second electrode; layering a second insulating material and a third conductive material on a second side of the substrate opposite the first side; selectively removing portions of the third insulating material to expose portions of the third conductive material to form a third electrode; and depositing an analyte sensing membrane on two of the first electrode, the second electrode, or the third electrode.

[0014] In an example, a method of making a plurality of analyte sensors may include generating a plurality of sensor substrates from a sheet of substrate material, where each of the plurality of sensor substrates is aligned on the sheet of substrate material; forming a working electrode and a reference electrode on each of the plurality of sensor substrates; and applying an analyte sensing membrane on each of the working electrodes on each of the plurality of sensor substrates.

[0015] In an embodiment, a method of fabricating an analyte sensor can include aligning a plurality of insulating layers and a plurality of conductive layers in an alternating manner, stacking the plurality of insulating layers and the plurality of conductive layers together, and selectively removing portions of the plurality of insulating layers to expose at least two electrodes.

[0016] In an embodiment, an analyte sensor can include a sensor substrate, a first electrode mechanically coupled to the sensor substrate, a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, a second electrode mechanically coupled to the sensor substrate, a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, and an analog front end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode trace, and electrically coupled to the second electrode trace.

[0017] In an example, an analyte sensor system can include an analyte sensor comprising a sensor substrate, a first electrode mechanically coupled to the sensor substrate, a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, a second electrode mechanically coupled to the sensor substrate, a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, and an analog front-end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode trace and electrically coupled to the second electrode trace, a sensor electronics assembly, and a connector electrically coupling the analog front-end circuit to the sensor electronics assembly. [Brief description of the drawings]

[0018] In the drawings, which are not necessarily drawn to scale, like numerals may describe like components in different views. Like numerals with different letter suffixes may represent different instances of the like components. The drawings illustrate generally, by way of example, and not by way of limitation, various embodiments discussed in the present document. [Figure 1] FIG. 1 illustrates an example of an environment including an analyte sensor system. [Diagram 2] FIG. 2 illustrates an example of a medical device system including the analyte sensor system of FIG. 1. [Figure 3A] 1 is an illustration of an exemplary analyte sensor. [Figure 3B] FIG. 3B is a cross-sectional view of the sensor of FIG. 3A taken along section line BB. [Figure 3C] 3B is a cross-sectional view of the sensor of FIG. 3A taken along section line CC. [Figure 3D] FIG. 3B is a cross-sectional view of the sensor of FIG. 3A taken along section line DD. [Figure 4A] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4B] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4C] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4D] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4E] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4F] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 4G] 1 illustrates a single-sided coplanar analyte sensor assembly, according to an embodiment. [Figure 5A] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5B] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5C] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5D] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5E] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5F]1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5G] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5H] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5I] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5J] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 5K] 1 illustrates a single-sided stacked analyte sensor assembly, according to an embodiment. [Figure 6A] 1 illustrates a double-sided, coplanar, non-connected analyte sensor, according to an embodiment. [Figure 6B] 1 illustrates a double-sided, coplanar, non-connected analyte sensor, according to an embodiment. [Figure 6C] 1 illustrates a double-sided, coplanar, non-connected analyte sensor, according to an embodiment. [Figure 6D] 1 illustrates a double-sided, coplanar, non-connected analyte sensor, according to an embodiment. [Figure 6E] 1 illustrates a double-sided, coplanar, non-connected analyte sensor, according to an embodiment. [Figure 7A] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7B] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7C] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7D] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7E] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7F] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7G] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7H]1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 7I] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8A] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8B] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8C] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8D] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8E] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 8F] 1 illustrates a double-sided flush-coupled analyte sensor, according to an embodiment. [Figure 9] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 10A] 1 illustrates a method of making a multi-layer co-planar analyte sensor assembly, according to an embodiment. [Figure 10B] 1 illustrates a method of making a multi-layer co-planar analyte sensor assembly, according to an embodiment. [Figure 11A] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 11B] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 11C] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 12] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 13] 1 illustrates a method of making a co-planar analyte sensor assembly, according to an embodiment. [Figure 14A] 1 illustrates a method of skiving a coplanar analyte sensor assembly, according to an embodiment. [Figure 14B]1 illustrates a method of skiving a coplanar analyte sensor assembly, according to an embodiment. [Figure 14C] 1 illustrates a method of skiving a coplanar analyte sensor assembly, according to an embodiment. [Figure 14D] 1 illustrates a method of skiving a coplanar analyte sensor assembly, according to an embodiment. [Figure 15A] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 15B] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 15C] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 15D] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 16A] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 16B] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 16C] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 16D] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 17A] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 17B] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 17C] 1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 17D]1 illustrates a coaxial analyte sensor assembly having radial wires in an insulating polymer, according to an embodiment. [Figure 18] 1 illustrates a coaxial analyte sensor assembly including a wire embedded in a photoresist insulating polymer, according to an embodiment. [Figure 19A] 1 illustrates a coaxial analyte sensor assembly including a polymer core, according to an embodiment. [Figure 19B] 1 illustrates a coaxial analyte sensor assembly including a polymer core, according to an embodiment. [Figure 20A] 1 illustrates a coaxial analyte sensor assembly including a wire core, according to an embodiment. [Figure 20B] 1 illustrates a coaxial analyte sensor assembly including a wire core, according to an embodiment. [Figure 21A] 1 illustrates a double-sided stacked planar analyte sensor, according to an embodiment. [Figure 21B] 1 illustrates a double-sided stacked planar analyte sensor, according to an embodiment. [Figure 22A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 22B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 23A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 23B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 23C] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 23D] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 24A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 24B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 25A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 25B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 25C] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 25D] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 25E] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 26A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 26B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 26C] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 27A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 27B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 27C] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 27D] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 28A] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 28B] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 28C] 1 illustrates a double-sided coplanar analyte sensor, according to an embodiment. [Figure 29] 1 illustrates a sensor tip design, according to an embodiment. [Diagram 30] 1 illustrates a sensor tip design, according to an embodiment. [Diagram 31] 1 illustrates a sensor tip design, according to an embodiment. [Diagram 32] 1 illustrates a sensor tip design, according to an embodiment. [Diagram 33] 1 illustrates a sensor tip design, according to an embodiment. [Diagram 34] 1 illustrates a sensor tip design, according to an embodiment. [Figure 35A] 1 illustrates an L-shaped sensor, according to an embodiment. [Figure 35B]1 illustrates an L-shaped sensor, according to an embodiment. [Diagram 36] 1 illustrates an L-shaped sensor, according to an embodiment. [Figure 37A] 1 illustrates a cubic sensor, according to an embodiment. [Figure 37B] 1 illustrates a cubic sensor, according to an embodiment. [Figure 37C] 1 illustrates a cubic sensor, according to an embodiment. [Figure 37D] 1 illustrates a cubic sensor, according to an embodiment. [Figure 38] 1 illustrates a cubic sensor on a circuit board, according to an embodiment. [Figure 39A] 1 illustrates a method for fabricating a cubic sensor, according to an embodiment. [Figure 39B] 1 illustrates a method for fabricating a cubic sensor, according to an embodiment. [Figure 39C] 1 illustrates a method for fabricating a cubic sensor, according to an embodiment. [Figure 39D] 1 illustrates a method for fabricating a cubic sensor, according to an embodiment. [Diagram 40] 1 depicts a flow diagram illustrating a method of making a planar analyte sensor membrane, according to an embodiment. [Diagram 41] FIG. 1 illustrates an example of an analyte sensor system that includes an analyte sensor electrically coupled to sensor electronics via a connector. [Diagram 42] FIG. 42 illustrates an exemplary arrangement of the analog front-end circuit of FIG. 41. [Diagram 43] FIG. 1 illustrates one exemplary arrangement of an analyte sensor with an analog front-end circuit. [Diagram 44] FIG. 44 illustrates another exemplary arrangement of the analyte sensor of FIG. 43. [Diagram 45] FIG. 1 illustrates another exemplary arrangement of an analyte sensor with an analog front-end circuit. [Diagram 46] FIG. 46 illustrates an embodiment of the analyte sensor of FIG. 45 with a housing molded onto the sensor substrate. [Figure 47]FIG. 1 illustrates another embodiment of an analyte sensor. [Figure 48] FIG. 1 illustrates an example of an analyte sensor system that includes an analyte sensor electrically coupled to sensor electronics via a contactless connector. [Figure 49] FIG. 1 shows one arrangement of an analyte sensor system that includes a sensor substrate having a coil positioned thereon. [Figure 50] FIG. 13 illustrates another arrangement of an analyte sensor system including sensor electronics via a contactless connector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The present disclosure describes, among other things, analyte sensors including both planar and cylindrical architectures and fabrication methods for more accurate and reproducible analyte monitoring results. Designs can include multiple sensing surfaces to enable sensing of more than one analyte on a single sensor. In some cases, multiple coating layers can be used to ensure proper functioning of the analyte sensor. The analyte sensors can be amenable to high speed and high throughput processes, allowing for efficient and flexible electronics manufacturing methods.

[0020] The exemplary analyte sensors described herein can be placed in contact with a bodily fluid of a host to measure the concentration of an analyte, such as glucose, in the bodily fluid. In other examples, two or more analytes discussed herein can be monitored instead of or in addition to glucose. In some examples, the analyte sensor is inserted subcutaneously under the skin of the host, thereby placing it in contact with interstitial fluid under the skin to measure the concentration of an analyte in the interstitial fluid.

[0021] When the analyte sensor is exposed to one or more analytes, a signal is generated and measured. In one embodiment, the signal is generated via an electrochemical reaction between the analyte sensor and the analyte. This electrochemical reaction can cause the analyte sensor to generate a raw sensor signal indicative of the analyte concentration. In some embodiments, the analyte sensor can include a working electrode (WE) and a reference electrode (RE). In other embodiments, the analyte sensor can also include a counter electrode (CE). In the presence of one or more analytes, the electrochemical reaction can cause a current to flow between the working electrode and the counter electrode, and the raw sensor signal can be based on the current. If present, the reference electrode can provide a stable reference potential and can conduct a very small current. In some cases, potentiometric measurements can be used in addition to such measurements obtained via amperometric measurements.

[0022] In the exemplary two-electrode configuration, the counter electrode can be omitted. In this case, the electrochemical reaction between the analyte sensor and the analyte can cause a current to form between the working electrode and the reference electrode. Thus, the reference electrode can conduct current like the counter electrode in the three-electrode configuration and provide a stable reference potential. The reference electrode in the two-electrode configuration can sometimes be referred to as a counter reference electrode. In this specification, the term reference electrode can be used to refer to the reference electrode in the three-electrode configuration, the counter reference electrode in the two-electrode configuration, or a similar electrode in other configurations, depending on the exemplary electrode configuration.

[0023] In use, the sensor electronics can apply a bias potential between the working electrode and a reference (e.g., counter-reference) electrode. In a two-electrode configuration, the applied bias can promote an electrochemical reaction between the analyte and the analyte sensor, resulting in a current flow between the working electrode and the reference (e.g., counter-reference) electrode. The current flow can constitute all or a portion of the raw sensor signal. The bias potential can be positive or negative and can be toggled between positive and negative values ​​or otherwise among and between values ​​depending on one or more analytes being monitored.

[0024] Many analyte sensors are currently manufactured for the detection of a single analyte, thus potentially requiring multiple sensors or even multiple systems to simultaneously detect and monitor multiple analytes. In some examples, the architecture of the sensor is related to the type or number of analytes that can be monitored. Thus, in some examples as discussed herein, the sensor architecture can be configured to detect and monitor two or more analytes simultaneously, or in an overlapping or toggle manner. Thus, improved functionality and expanded use of continuous monitoring sensors to detect multiple analytes on a single sensor can be useful. Similarly, in some examples, it may be desirable to have a sensor architecture that can be produced quickly and cost-effectively so that the needs of the health care community, including, for example, underserved communities, can be met.

[0025] Two different classes of analyte sensor architectures are considered herein: planar and coaxial, each of which can potentially offer multiple advantages over previous wire-based architectures.

[0026] For example, planar-based analyte sensors can be scaled up for production while still providing flexible geometries. In particular, planar configurations can be amenable to high-speed, high-throughput processes, such as sheet-to-sheet or reel-to-reel manufacturing methods. Such flexible electronic manufacturing methods can include photolithography, plating, or high-definition printing methods, such as inkjet printing or screen printing. Planar architectures can additionally enable multi-analyte sensing.

[0027] Coaxial-based analyte sensors can incorporate multiple sensing surfaces, allowing for efficient sensing of two or more analytes on a single sensor. Also, production of coaxial or cylindrical sensors can be easily scaled, as production can be accomplished by extrusion and coating (e.g., individual dispensing, spray coating, or dip coating). These methods can enable rapid production of continuous analyte and continuous multi-analyte monitoring devices that are cost-effective and time-effective, safe, reliable, and effective. Continuous analyte monitoring systems employing the sensor architectures discussed herein can enable increased sensor wear time, reduced break-in time, improved accuracy, reduced drift, and increased patient comfort and potential compliance with pharmaceutical regimens or other health or nutritional plans, including corrective or preventative measures.

[0028] definition As used herein, the terms and phrases "analyte measuring device," "biosensor," "sensor," "sensing area," and "sensing mechanism" are broad terms and phrases that are to be given their ordinary and customary meaning to one of skill in the art (and are not to be limited to any special or customized meaning) and refer to, but are not limited to, an area of ​​an analyte monitoring device that is responsible for the detection of, or the transduction of a signal associated with, a particular analyte or combination of analytes. In one embodiment, such devices are capable of providing specific quantitative, semi-quantitative, qualitative, or semi-qualitative analytical information using a biological recognition element combined with a transduction (detection) element.

[0029] As used herein, the term "about" allows for some variability in values ​​or ranges, e.g., within 10%, within 5%, or within 1% of a stated value or a stated range limit, and includes the precisely stated value or range. As used herein, the term "substantially" refers to a majority or majority, such as at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%. As used herein, the term "substantially free" can mean having no or an insignificant amount of the material, such that the amount of the material present does not affect the material properties of the composition including the material, and from about 0% to about 5% by weight of the composition is the material, or from about 0% to about 1%, or about 5% by weight or less, or about 4.5% by weight or less, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001% by weight or less, or about 0% by weight.

[0030] As used herein, the terms "adhere" and "attach" are broad terms and are to be given their ordinary and accustomed meaning to those of skill in the art (and are not to be limited to any special or customized meaning), including, but not limited to, holding, joining, or fastening, for example, by adhering, bonding, grasping, interpenetrating, or fusing.

[0031] As used herein, the term "analyte" is a broad term and is to be given its ordinary and customary meaning to one of skill in the art (and is not to be limited to any special or customized meaning) and refers to, but is not limited to, a substance or chemical constituent in a biological fluid (e.g., blood, interstitial fluid, sweat, cerebrospinal fluid, lymphatic fluid, or urine) that can be analyzed. Analytes can include naturally occurring substances, man-made substances, metabolites, and / or reaction products. In some examples, the analyte for measurement by the sensing regions, devices, and methods is glucose. However, other analytes are contemplated, including, but not limited to: carboxyprothrombin; acylcarnitines; adenine phosphoribosyltransferase; adenosine deaminase; albumin; alpha-fetoprotein; amino acid profile (arginine (Krebs cycle), histidine / urocanic acid, homocysteine, phenylalanine / tyrosine, tryptophan); andrenostenedione; antipyrine; arabinitol enantiomers; arginase; benzoylecgonine (cocaine); biotinidase; biopterin; c-reactive protein; carnitine; carnosinase; CD4; ceruloplasmin; chenodeoxycholic acid; chloroquine; cholesterol; cholinesterase; conjugated 1-beta hydroxy-cholic acid; cortisol; creatinine, creatinine creatine kinase MM isoenzyme;cyclosporine A;d-penicillamine;deethylchloroquine;dehydroepiandrosterone sulfate;DNA (acetylation polymorphism, alcohol dehydrogenase, alpha 1-antitrypsin, cystic fibrosis, Duchenne / Becker muscular dystrophy, glucose-6-phosphate dehydrogenase, hemoglobin A, hemoglobin S, hemoglobin C, hemoglobin D, hemoglobin E, hemoglobin F, D-Punjab, beta-thalassemia, hepatitis B virus, HCMV, HIV-1, HTLV-1, Leber's hereditary optic neuropathy, MCAD, RNA, PKU, Plasmodium vivax, 21-deoxycortisol);desbutylhalofantrine;dihydropteridine reductase;diphtheria / tetanus antitoxin;erythrocyte arginase;erythrocyte protoporphyrin;esterase D;Fatty acids / acylglycines;free beta-human chorionic gonadotropin;free erythrocyte porphyrins;free thyroxine (FT4);free tri-iodothyronine (FT3);fumarylacetoacetase;galactose / gal-1-phosphate;galactose-1-phosphate uridyltransferase;gentamicin;glucose-6-phosphate dehydrogenase;glutathione;glutathione peroxidase;glycerol, glycocholate;glycosylated hemoglobin;halofantrine;hemoglobin variants;hexosaminidase A;human erythrocyte carbonic anhydrase I;17-alpha-hydroxyproline Gesterone; hypoxanthine phosphoribosyltransferase; immunoreactive trypsin; beta-hydroxybutyrate; ketones; lactate; lead; lipoproteins ((a), B / A-1, β); lysozyme; mefloquine; netilmicin; phenobarbitone; phenytoin; phytanic acid / pristanic acid; potassium (or other blood electrolytes); progesterone; prolactin; prolidase; purine nucleoside phosphorylase; quinine; reverse triiodothyronine (reverse tri-iodothyronine, rT3); selenium; serum pancreatic lipase; sisomicin; sodium; somatomedin C; specific antibodies (adenovirus, antinuclear antibodies, anti-zeta antibodies, arbovirus, pseudorabies virus, dengue virus, dracunculiasis, tapeworm, ameba granulosus, enterovirus, giardiasis, Helicobacter pylori, hepatitis B virus, herpes virus, HIV-1, IgE (atopic disease), influenza virus, Leishmania donovani, Leptospira, measles / mumps subcutaneous sputum / rubella, Mycobacterium leprae, Mycoplasma pneumoniae, myoglobin, Onchocerca volvulus, parainfluenza virus, malaria parasite, poliovirus, Pseudomonas aeruginosa, respiratory syncytial virus, Rickettsia (tsutsugamushi disease), Schistosoma mansoni, Toxoplasma gondii, Treponema pallidum, Trypanosoma cruzi / rangeli, vesicular stomatitis virus, Wuchereria bancrofti, yellow fever virus); specific antigens (Hepatitis B virus, HIV-1); succinylacetone; sulfadoxine; theophylline; thyrotropin (TSH); thyroxine (T4);thyroxine-binding globulin; trace elements; transferrin; UDP-galactose-4-epimerase; urea; uroporphyrinogen I synthase; vitamin A; leukocytes; and zinc protoporphyrin. Salts, sugars, proteins, fats, vitamins, and hormones naturally present in blood or interstitial fluids can also constitute analytes in certain embodiments. Analytes can also be naturally present in biological fluids, e.g., metabolites, hormones, antigens, antibodies, and the like. Alternatively, analytes can be introduced into the body. For example, contrast agents for imaging, radioisotopes, chemical agents, fluorocarbon-based synthetic blood, or drugs or pharmaceutical compositions, including, but not limited to, insulin; ethanol; cannabis (marijuana, tetrahydrocannabinol, hashish); inhalants (nitrous oxide, amyl nitrite, butyl nitrite, chlorohydrocarbons, hydrocarbons); cocaine (crack cocaine); stimulants (amphetamine, methamphetamine, Ritalin, Silurt, Preludine, Didrex, Prestate, Boranil, Sandrex, Pregin); antidepressants (barbiturates, tranquilizers such as methaqualone, valium, librium, miltuna, serax, equanil, tranxine; hallucinogens (phencyclidine, lysergic acid, mescaline, peyote, psilocybin); narcotics (heroin, codeine, morphine, opium, meperidine, percocet, percodan, tasionex, fentanyl, darvon, talwin, lomotil); synthetic narcotics (fentanyl, meperidine, amphetamine, methamphetamine, and phencyclidine analogues, e.g., ecstasy); anabolic steroids;Analytes that can be analyzed include, but are not limited to, nicotine, and nicotine. Metabolic products of drugs and pharmaceutical compositions are also contemplated analytes. Analytes such as neurochemicals and other chemicals produced in the body, such as ascorbic acid, uric acid, dopamine, noradrenaline, 3-methoxytyramine (3MT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxytryptamine (5HT), 5-hydroxyindoleacetic acid (FHIAA), and histamine, can also be analyzed.

[0032] As used herein, the term "bioactive agent" is a broad term and is to be given its ordinary and accustomed meaning to those of skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, any substance that has an effect on or elicits a response from living tissue.

[0033] As used interchangeably herein, the phrases "biointerface membrane" and "biointerface layer" and "biointerface / drug-releasing membrane" and "biointerface / drug-releasing layer" are broad phrases that are to be given their ordinary and accustomed meaning to one of ordinary skill in the art (and are not to be limited to any special or customized meaning) and refer to, but are not limited to, a permeable membrane or layer that serves as an interface between a host tissue and an implantable device.

[0034] As used herein, the phrase "barrier cell layer" is a broad term that is to be given its ordinary and customary meaning to one of skill in the art (and is not to be limited to any special or customized meaning), and refers, without limitation, to the portion of the foreign body reaction that forms a cohesive monolayer of cells (e.g., macrophages and foreign body giant cells) that substantially blocks the transport of molecules and other substances into the implantable device.

[0035] As used herein, the term "biostable" is a broad term that is to be given its ordinary and accustomed meaning to those of skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, materials that are relatively resistant to degradation by processes encountered in vivo.

[0036] As used herein, the term "bioresorbable" or "bioabsorbable" is a broad term that is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning) and refers to, but is not limited to, materials that are capable of being absorbed or that may lose substances in a biological system.

[0037] As used herein, the phrase "cell process" is a broad term that is to be given its ordinary and customary meaning to those of skill in the art (and is not to be limited to any special or customized meaning) and refers to, but is not limited to, the pseudopodia of cells.

[0038] As used herein, the phrase "cell attachment" is a broad term and is given its ordinary and customary meaning to those skilled in the art (and is not limited to any special or customized meaning), and refers to, but is not limited to, the adhesion of cells and / or cell processes to a material at a molecular level and / or the attachment of cells and / or cell processes to a microporous or macroporous material surface. One example of a material used in the prior art that promotes cell attachment to a porous surface is the BIOPORE™ cell culture support, as marketed by Millipore (Bedford, Mass) and described in U.S. Patent No. 5,741,330 to Brauker et al.

[0039] As used herein, the term "continuous" is a broad term and is to be given its ordinary and accustomed meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, an uninterrupted or unbroken portion, domain, coating, or layer.

[0040] As used herein, the term "co-continuous" is a broad term that is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning) and refers to, but is not limited to, a solid portion or cavity that allows for a three-dimensional unbroken curve to be drawn between the two sides of the membrane.

[0041] As used herein, the term "coaxial" should be interpreted broadly to include sensor architectures having elements aligned along a shared axis about a core that may be configured to have a circular, elliptical, triangular, polygonal, or other cross-section, and such elements may include electrodes, insulating layers, or other elements that may be positioned circumferentially about a core layer, such as a core electrode or core polymer wire.

[0042] Further examples of continuous analyte sensors can be found, for example, in U.S. Pat. No. 8,828,201 to Simpson et al., U.S. Pat. No. 9,131,885 to Simpson et al., U.S. Pat. No. 9,237,864 to Simpson et al., and U.S. Pat. No. 9,763,608 to Simpson et al., each of which is incorporated by reference in its entirety herein.

[0043] As used herein, the phrase "continuous analyte sensing" is a broad phrase and is to be given its ordinary and accustomed meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning) and refers to a period during which monitoring of analyte concentration is performed continuously, continuously, and / or intermittently (but periodically), e.g., for a period of time ranging from about 5 seconds or less to about 10 minutes or more, preferably about 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 210, 220, 230, 240, 250, 260, 270, 280, 290, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, 750, 760, 770, 780, 790, 800 This refers to, but is not limited to, every 55 or 60 seconds to about 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, 3.00, 3.25, 3.50, 3.75, 4.00, 4.25, 4.50, 4.75, 5.00, 5.25, 5.50, 5.75, 6.00, 6.25, 6.50, 6.75, 7.00, 7.25, 7.50, 7.75, 8.00, 8.25, 8.50, 8.75, 9.00, 9.25, 9.50 or 9.75 minutes.

[0044] As used herein, the terms "co-planar" or "coplanar" can refer to two or more electrodes or other components on a substrate, which two or more electrodes or other components reside in substantially the same plane.

[0045] As used herein, the term "coupled" may refer to two or more system elements or components that are configured to be at least one of electrically, mechanically, thermally, operatively, chemically, or otherwise attached.

[0046] As used herein, the term "removably coupled" may refer to two or more system elements or components that are configured or configured to be electrically, mechanically, thermally, operatively, chemically, or otherwise attached and detached without damaging any of the coupled elements or components.

[0047] As used herein, the term "permanently coupled" may refer to two or more system elements or components that are configured or attached electrically, mechanically, thermally, operatively, chemically, or otherwise attached, but cannot be uncoupled without damaging at least one of the coupled elements or components.

[0048] As used herein, the phrase "defined edge" is a broad phrase and is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, an abrupt, distinct edge or boundary between layers, domains, coatings, or portions. A "defined edge" is in contrast to a gradual transition between layers, domains, coatings, or portions.

[0049] As used herein, the term "discontinuous" is a broad term and is to be given its ordinary and accustomed meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, cut, interrupted, or separated portions, layers, coatings, or domains.

[0050] As used herein, the term "distal" is a broad term and is to be given its ordinary and accustomed meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, an area that is relatively far away from a reference point such as an origin or an attachment point.

[0051] As used herein, the term "domain" is a broad term and is given its ordinary and customary meaning to those skilled in the art (and is not limited to any special or customized meaning) and refers to, but is not limited to, a layer, a uniform or non-uniform gradient (e.g., an anisotropic region of a membrane), or a region of a membrane system that may be a portion of a membrane. The domains discussed herein can be formed as a single layer, as two or more layers, as a pair of bilayers, or as a combination thereof. As used herein, the term "drift" is a broad term and is given its ordinary and customary meaning to those skilled in the art (and is not limited to any special or customized meaning) and refers to, but is not limited to, a gradual increase or decrease in a signal over time that is independent of changes in host systemic analyte concentration, such as, for example, host postprandial glucose concentration. Without wishing to be bound by theory, it is believed that drift may be the result of a local decrease in glucose transport to the sensor, for example, due to cellular infiltration surrounding the sensor and forming a FBC. It is also believed that an insufficient amount of interstitial fluid surrounds the sensor, which may result in, for example, reduced oxygen and / or glucose transport to the sensor. Increasing the local interstitial fluid may slow or reduce drift, thus improving sensor performance. Drift may also be the result of the sensor electronics or algorithmic models used to compensate for noise or other anomalies that can occur with electrical signals in the picoamp range.

[0052] As used interchangeably herein, the phrases "drug release membrane" and "drug release layer" are each broad phrases that are given their ordinary and customary meaning to one of ordinary skill in the art (and are not limited to any special or customized meaning), and refer to, but are not limited to, a permeable or semi-permeable membrane that is permeable to one or more bioactive agents. In one embodiment, the "drug release membrane" and "drug release layer" may be composed of two or more domains, typically several microns or more thick. In one embodiment, the drug release layer and / or drug release membrane are substantially the same as the biointerface layer and / or biointerface membrane. Examples of drug release layers and membranes can be found in pending U.S. Patent Application Publication No. 2022-0296867, entitled "DRUG RELEASING MEMBRANE FOR ANALYTE SENSOR," filed March 17, 2022, which is incorporated by reference in its entirety, and pending U.S. Patent Application No. 17 / 945585, entitled "DRUG RELEASING MEMBRANE FOR ANALYTE SENSOR," filed March 17, 2022, which is incorporated by reference in its entirety.

[0053] As used herein, the term "electrochemically reactive surface" is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, the surface of an electrode where an electrochemical reaction occurs. At the working electrode, redox species are generated by an enzyme-catalyzed reaction of an analyte and can produce a measurable electronic current that is used to determine the concentration of the analyte. At some examples of the working electrode, oxidizable species generated by the reaction of the analyte to be detected can produce a measurable electronic current. For example, in the detection of glucose, glucose oxidase produces hydrogen peroxide (H2O2) as a by-product. H2O2 reacts with the surface of the working electrode to produce two protons (2H+), two electrons (2e-), and one oxygen molecule (O2), which produces the electronic current that is detected. At the counter electrode, reducible species, e.g., O2, are reduced at the electrode surface to balance the current produced by the working electrode.

[0054] As used herein, the term "host" is a broad term given its ordinary and accustomed meaning to those of skill in the art (and is not intended to be limited to any special or customized meaning), and refers to, but is not limited to, a mammal, preferably a human.

[0055] As used herein, the terms "interfering substance" and "interfering species" are broad terms and are to be given their ordinary and customary meaning to one of skill in the art (and are not to be limited to any special or customized meaning), and refer to, but are not limited to, effects and / or species that interfere with the measurement of an analyte of interest in a sensor, producing a signal that does not accurately represent the analyte measurement. In one example of an electrochemical sensor, an interfering species is a compound that has an oxidation potential that overlaps with the analyte being measured.

[0056] The term "in vivo" refers, without limitation, to a portion of a device (eg, a sensor) that is adapted for insertion into and / or presence within a host's living body.

[0057] The term "ex vivo" refers to a portion of a device (eg, a sensor) that is adapted to reside and / or exist outside the host organism.

[0058] As used herein, the phrase "membrane system" is a broad phrase and is to be given its ordinary and customary meaning to one of ordinary skill in the art (and is not to be limited to any special or customized meaning) and refers, but is not limited to, a permeable or semi-permeable membrane that may be composed of two or more domains, is composed of material that is typically several microns thick or more, and is permeable to oxygen and, optionally, for example, to glucose or another analyte. In one example, the membrane system includes an immobilized glucose oxidase enzyme that allows a reaction to occur between glucose and oxygen, thereby allowing glucose concentration to be measured. As used herein, the term "noise" is a broad term and is used in its ordinary sense, and includes, but is not limited to, a signal detected by the sensor or sensor electronics that is independent of analyte concentration and may result in degradation of sensor performance. One type of noise is observed for several hours (e.g., about 2 to about 24 hours) after sensor insertion. After the first 24 hours, the noise may disappear or decrease, but in some hosts, the noise may persist for about 3 to 4 days. In some cases, the noise may be reduced using predictive modeling, artificial intelligence, and / or algorithmic means. In other cases, noise can be reduced by addressing immune response factors associated with the presence of an embedded sensor, such as by using a drug-releasing layer having at least one bioactive agent. For example, the noise of one or more exemplary biosensors as disclosed herein can be determined and then qualitatively or quantitatively compared. As an example, obtaining a raw signal time series at a fixed sampling interval (in picoamps (pA)) a smoothed version of the raw signal time series can be obtained, for example, by applying a third order low-pass digital Chebyshev Type II filter. Other smoothing algorithms can also be used. At each sampling interval, the absolute difference in pA can be calculated to provide a smoothed time series.This smoothed time series can be converted to units of mg / dL (units of "noise") using the glucose sensitivity time series in units of pA / mg / dL, which is derived using a mathematical model between the raw signal and a reference blood glucose measurement (e.g., obtained from a blood glucose meter). Optionally, the time series can be aggregated, for example, by hour or day, as desired. Comparison of corresponding time series between different exemplary biosensors having a drug-releasing layer and one or more bioactive agents of the present disclosure provides a qualitative or quantitative determination of the noise improvement.

[0059] As used herein, the terms "operably connected," "operably coupled," and "operably linked" are broad terms and are to be given their ordinary and customary meaning to one of ordinary skill in the art (and are not to be limited to any special or customized meaning), and refer to, but are not limited to, one or more components that are linked to another component in a manner that facilitates the transmission of a signal between the components. For example, one or more electrodes can be used to detect an analyte in a sample and convert that information into a signal, which can then be transmitted to an electronic circuit. In this example, the electrodes are "operably linked" to the electronic circuit.

[0060] The term "optionally" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances when the event or circumstance does and does not occur.

[0061] As used herein, the term "planar" should be interpreted broadly to describe a sensor architecture having a substrate including a first side and a second side, and a plurality of elements disposed on one or more sides of the substrate, which may or may not be electrically or otherwise coupled, and which may include conductive or insulating layers or elements configured to operate as a circuit. A planar electrode, for example, has a generally flat or horizontal surface.

[0062] As used herein, the term "proximal" is a broad term and is given its ordinary and customary meaning to one of ordinary skill in the art (and is not limited to any special or customized meaning), and refers to, but is not limited to, the spatial relationship between various elements compared to a particular reference point. For example, some embodiments of the device include a membrane system having a biointerface layer and an enzyme layer. If the sensor is considered to be the reference point and the enzyme layer is positioned closer to the sensor than the biointerface layer, then the enzyme layer is more proximal to the sensor than the biointerface layer.

[0063] As used herein, the phrases and terms "processor module" and "microprocessor" are broad terms and are to be given their ordinary and customary meaning to those skilled in the art (and are not to be limited to any special or customized meaning) and refer to, but are not limited to, computer systems, state machines, processors, and the like, designed to perform arithmetic or logical operations using logic circuits that respond to and process basic instructions that drive a computer. As used herein, the term "semi-continuous" is broad terms and are to be given their ordinary and customary meaning to those skilled in the art (and are not to be limited to any special or customized meaning) and refer to, but are not limited to, a portion, coating, domain, or layer that includes one or more continuous and non-continuous portions, coatings, domains, or layers. For example, a coating that is disposed around but not over a sensing area is "semi-continuous."

[0064] As used herein, the term "sensing membrane" is a broad term and is to be given its ordinary and customary meaning to one of skill in the art (and is not to be limited to any special or customized meaning), and refers to, but is not limited to, a permeable or semi-permeable membrane that may include one or more domains within a membrane system, is composed of a material having a thickness of several microns or more, and is permeable to reactants and / or co-reactants used in determining an analyte of interest. By way of example, the sensing membrane may include immobilized glucose oxidase enzyme that catalyzes an electrochemical reaction with glucose and oxygen to allow for the measurement of glucose concentration.

[0065] Analyte Sensor System FIG. 1 illustrates an example of an environment 100 including an analyte sensor system 102 configured to continuously monitor two or more analytes. The analyte sensor system 102 may be coupled to a host 101, which may be a human patient. In some cases, the host may be subject to a temporary or permanent diabetic condition or other health condition that makes monitoring of the analytes useful. The analyte sensor system 102 may include an analyte sensor 104 configured to detect one or more analytes. In some examples, the analyte sensor 104 may include a glucose sensor configured to measure a glucose concentration within the host 101. The analyte sensor 104 may be exposed to the analytes at the host 101 in any suitable manner. In some cases, the analyte sensor 104 may be fully implantable under the skin of the host 101. In other examples, the analyte sensor 104 may be wearable on the body of the host 101. Additionally, in some embodiments, the analyte sensor 104 may be a transcutaneous device (eg, a device that includes a sensor, such as the analyte sensor 104, that resides at least partially beneath or in the skin of the host).

[0066] In an embodiment, the glucose detected can be D-glucose. However, any stereoisomer or blend of stereoisomers of glucose, as well as any glucose in open chain, cyclic, or mixtures thereof, can be detected. In the embodiment of FIG. 1, the analyte sensor system 102 can also include sensor electronics 106. In some embodiments, the sensor electronics 106 and the analyte sensor 104 can be provided in a single integrated package. In other embodiments, the analyte sensor 104 and the sensor electronics 106 can be provided as separate components or modules. For example, the analyte sensor system 102 can include a disposable (e.g., single-use) sensor attachment unit, which can include the analyte sensor 104, components for attaching the sensor 104 to a host (e.g., an adhesive pad), and / or a mounting structure configured to receive a sensor electronics unit including some or all of the sensor electronics 106 shown in FIG. 2. The sensor electronics unit can be reusable.

[0067] The analyte sensor 104 may use a variety of methods, including invasive, minimally invasive, or non-invasive sensing techniques (e.g., optically stimulated fluorescence, microneedle, transdermal monitoring of glucose) to provide a raw sensor signal indicative of the concentration of the analyte in the host 101. The raw sensor signal may be converted into calibrated and / or filtered analyte concentration data that is used to provide a useful value of the analyte concentration (e.g., an estimated blood glucose concentration level) to a user, such as the host or a caretaker (e.g., a parent, relative, guardian, teacher, doctor, nurse, or any other individual interested in the health status of the host 101).

[0068] In some examples, the analyte sensor 104 can include a continuous glucose sensor. The continuous glucose sensor can be or can include a subcutaneous, transcutaneous (e.g., transdermal), or intravascular device. In some cases, such a sensor or device can analyze the sensor data repeatedly (e.g., periodically or intermittently). The glucose sensor can use any glucose measurement method, including enzymatic, chemical, physical, electrochemical, spectrophotometric, polarimetric, calorimetric, iontophoretic, radiometric, immunochemical, etc.

[0069] The environment 100 can also include a second medical device 108. The second medical device 108 can be or can include a drug delivery device, such as an insulin pump or an insulin pen. In some examples, the medical device 108 can include one or more sensors, such as another analyte sensor, a heart rate sensor, a respiration sensor, a motion sensor (e.g., an accelerometer), a posture sensor (e.g., a three-axis accelerometer), an acoustic sensor (e.g., to capture ambient or internal sounds), an oxygen sensor, a temperature sensor, and others. The medical device 108 can be, for example, wearable in a watch, glasses, contact lenses, a patch, a wristband, an ankle band, or another wearable item, or can be incorporated into a handheld device (e.g., a smartphone). In some examples, the medical device 108 may include a multi-sensor patch that can detect, for example, one or more of an analyte level (e.g., glucose, lactate, insulin, or other substance), heart rate, respiration (e.g., using impedance), activity (e.g., using an accelerometer), posture (e.g., using an accelerometer), galvanic skin response, tissue fluid levels (e.g., using impedance or pressure).

[0070] In some examples, the analyte sensor system 102 and the second medical device 108 communicate with each other. The communication between the analyte sensor system 102 and the medical device 108 can occur via any suitable wired connection and / or via wireless communication signals 110. For example, the analyte sensor system 102 can be configured to communicate via radio frequency (e.g., communication protocols such as Bluetooth, Medical Implant Communication System (MICS), Wi-Fi, near field communication (NFC), radio frequency identification (RFID), Zigbee, Z-Wave, etc.), optical (e.g., infrared), sonic (e.g., ultrasound), or cellular protocols (e.g., Code Division Multiple Access (CDMA) or Global System for Mobiles (GSM)), or wired connections (e.g., serial, parallel, etc.).

[0071] In some examples, the environment 100 can also include a wearable sensor 130. The wearable sensor 130 can include a sensor circuit (e.g., a sensor circuit configured to detect a glucose concentration or other analyte concentration) and a communication circuit, which can be, for example, an NFC circuit. In some examples, information from the wearable sensor 130 can be retrieved from the wearable sensor 130 using a user device 132, such as a smartphone, configured to communicate with the wearable sensor 130 via the communication circuit of the wearable sensor when the user device 132 is placed near the wearable sensor 130. For example, swiping the user device 132 over the wearable sensor 130 can retrieve sensor data from the wearable sensor 130 using NFC or other suitable wireless communication. Using NFC communication can reduce power consumption by the wearable sensor 130, which can reduce the size of a power source (e.g., a battery or capacitor) in the wearable sensor 130 or extend the usable life of the power source. In some examples, the wearable sensor 130 can be wearable on the upper arm, as shown. In some examples, the wearable sensor 130 can additionally or alternatively be on the patient's upper torso (e.g., over the heart or over the lungs), which can facilitate detection of, for example, heart rate, respiration, or posture. The wearable sensor 136 can also be on the lower body (e.g., the legs).

[0072] In some examples, an array or network of sensors can be associated with the patient. For example, one or more of the analyte sensor system 102, the medical device 108, the wearable device 120, such as a wristwatch, and the additional wearable sensor 130 can communicate with each other via wired or wireless (e.g., Bluetooth, MICS, NFC, or any of the other options described above) communication. The additional wearable sensor 130 can be any of the examples described above with respect to the medical device 108. The analyte sensor system 102, the medical device 108, and the additional wearable sensor 130 on the host 101 are provided for illustration and explanation and are not necessarily drawn to scale.

[0073] The environment 100 may also include one or more computing devices, such as a handheld smart device (e.g., smart device) 112, a tablet 114, a smart pen 116 (e.g., an insulin delivery pen with processing and communication capabilities), a computer 118, a wearable device 120 such as a wristwatch, or a peripheral medical device 122 (which may be a proprietary device such as a proprietary user device available from DexCom), any of which may communicate with the analyte sensor system 102 via wireless communication signals 110 and may also communicate with a server system (e.g., a remote data center) or remote terminal 128 via a network 124 to facilitate communication with a remote user (not shown), such as a technical support staff member or a clinician.

[0074] The wearable device 120 may include an activity sensor, a heart rate monitor (e.g., an optical or electrode-based sensor), a respiration sensor (e.g., an acoustic or electrode-based sensor), a location sensor (e.g., GPS), or other sensors.

[0075] In some examples, environment 100 can include a server system 126. Server system 126 can include one or more computing devices, such as one or more server computing devices. In some examples, server system 126 is used to collect analyte data from analyte sensor system 102 and / or analyte or other data from multiple other devices, perform analysis on the collected data, generate or apply universal or individualized models for glucose values, and communicate such analysis, models, or information based thereon back to one or more devices in environment 100. In some examples, server system 126 collects inter-host and / or intra-host break-in data to generate one or more break-in characteristics, as described herein.

[0076] The environment 100 may also include a wireless access point (WAP) 138 that is used to communicatively couple one or more of the analyte sensor system 102, the network 124, the server system 126, the medical device 108, or any of the peripheral devices described above. For example, the WAP 138 may provide Wi-Fi and / or cellular connectivity within the environment 100. Other communication protocols, such as NFC or Bluetooth, may also be used between devices in the environment 100.

[0077] FIG. 2 illustrates an example of a medical device system 200 including the analyte sensor system 102 of FIG. 1. In the example of FIG. 2, the analyte sensor system 102 can include a sensor electronics 106 and a sensor mounting unit 290. In the example shown in FIG. 2, the sensor mounting unit 290 can include an analyte sensor 104 and a battery 292. In some examples, the sensor mounting unit 290 can be replaceable and the sensor electronics 106 can include a debounce circuit (e.g., a gate with hysteresis or delay), for example, to avoid repeated execution of a power-up or power-down process when the battery is repeatedly connected and disconnected, or to avoid processing noise signals associated with removing or replacing a battery. The sensor electronics 106 can be configured to monitor two or more analytes sequentially. The two or more analytes can be monitored sequentially or alternately or in other patterns, for example, to predict and prevent adverse health events, such as hypoglycemia, hyperglycemia, or early stages of organ failure.

[0078] The sensor electronics 106 may include electronic components configured to process sensor information, such as a raw sensor signal, to generate a corresponding analyte concentration value. The sensor electronics 106 may include electronic circuitry associated with measuring, processing, storing, or communicating continuous analyte sensor data, including, for example, predictive algorithms associated with processing and calibrating the raw sensor signal. The sensor electronics 106 may include hardware, firmware, and / or software that enables the measurement of analyte values ​​via the glucose sensor. The electronic components may be affixed to a printed circuit board (PCB), or the like, and may take a variety of forms. For example, the electronic components may take the form of an integrated circuit (IC), such as an Application-Specific Integrated Circuit (ASIC), a microcontroller, and / or a processor.

[0079] In the example of FIG. 2, the sensor electronics 106 can include a measurement circuit 202 (e.g., a potentiostat) coupled to the analyte sensor 104 and configured to use the analyte sensor 104 to repeatedly obtain analyte sensor readings. For example, the measurement circuit 202 can continuously or repeatedly measure a raw sensor signal indicative of current flow in the analyte sensor 104 between a working electrode and a counter or reference (e.g., counter-reference) electrode. The sensor electronics 106 can include a gating circuit 294 that can be used to gate a connection between the measurement circuit 202 and the analyte sensor 104. For example, the analyte sensor 104 can accumulate charge over an accumulation period. After the accumulation period, the gating circuit 294 is opened to allow the measurement circuit 202 to measure the accumulated charge. Gating the analyte sensor 104 can improve the performance of the sensor system 102 by creating a greater signal-to-noise or interference ratio (e.g., because charge from the analyte reaction accumulates while interference sources, such as the presence of acetaminophen near the glucose sensor, do not accumulate or accumulate less than the charge from the analyte reaction).

[0080] The sensor electronics 106 can also include a processor 204. The processor 204 is configured to retrieve instructions 206 from the memory 208 and execute the instructions 206 to control various operations in the analyte sensor system 102. For example, the processor 204 can be programmed to control the application of a bias potential to the analyte sensor 104 via a potentiostat in the measurement circuit 202, interpret a raw sensor signal from the analyte sensor 104, and / or compensate for environmental factors. The processor 204 can also store information in or retrieve information from the data storage memory 210. In various embodiments, the data storage memory 210 can be integrated with the memory 208 or can be a separate memory circuit, such as a non-volatile memory circuit (e.g., flash RAM).

[0081] The sensor electronics 106 may also include a sensor 212 that may be coupled to the processor 204. The sensor 212 may be a temperature sensor, an accelerometer, or another suitable sensor. The sensor electronics 106 may also include a power source, such as a capacitor or battery 214, which may be integrated into the sensor electronics 106, may be removable, or may be part of a separate electronics unit. The battery 214 (or other power storage component, e.g., a capacitor) may optionally be rechargeable via a wired or wireless (e.g., inductive or ultrasonic) recharging system 216. The recharging system 216 may harvest energy, may receive energy from an external or on-board source, or may harvest energy from body heat (e.g., thermoelectric effect). In various embodiments, the recharging circuit may include a circuit that harvests energy from a triboelectric charging circuit, a piezoelectric charging circuit, an RF charging circuit, an optical charging circuit, an ultrasonic charging circuit, a thermal charging circuit, a thermal harvesting circuit, or a communication circuit. In some embodiments, the recharging circuitry may recharge the rechargeable battery using power provided from a replaceable battery (eg, a battery provided with the base component).

[0082] The sensor electronics 106 may also include one or more supercapacitors in the sensor electronics unit (as shown) or in the sensor mounting unit 290. For example, the supercapacitor may allow for energy to be drawn from the battery 214 in a very consistent manner to extend the life of the battery 214. The battery 214 may recharge the supercapacitor after it has provided energy to the communication circuitry or processor 204, so that the supercapacitor is ready to provide energy during a subsequent period of high load. In some embodiments, the supercapacitor may be configured in parallel with the battery 214. The device may be configured to preferentially draw energy from the supercapacitor as opposed to the battery 214. In some embodiments, the supercapacitor may be configured to accept energy from a rechargeable battery for short-term storage and transfer energy to the rechargeable battery for long-term storage.

[0083] The supercapacitor can extend the operating life of the battery 214 by reducing strain on the battery 214 during periods of high load. In some embodiments, the supercapacitor removes at least 10% of the strain on the battery during a high load event. In some embodiments, the supercapacitor removes at least 20% of the strain on the battery during a high load event. In some embodiments, the supercapacitor removes at least 30% of the strain on the battery during a high load event. In some embodiments, the supercapacitor removes at least 50% of the strain on the battery during a high load event.

[0084] The sensor electronics 106 can also include wireless communication circuitry 218, which can include, for example, a wireless transceiver operably coupled to an antenna. The wireless communication circuitry 218 can be operably coupled to the processor 204 and can be configured to wirelessly communicate with one or more peripheral devices or other medical devices, such as an insulin pump or a smart insulin pen.

[0085] In the example of FIG. 2, the medical device system 200 can also include an optional peripheral device 250. The peripheral device 250 can be any suitable user computing device, such as, for example, a wearable device (e.g., an activity monitor) such as the wearable device 120. In other examples, the peripheral device 250 can be a handheld smart device (e.g., a smartphone or other device such as a proprietary handheld device available from Dexcom), a tablet 114, a smart pen 116, or a dedicated computer 118 shown in FIG. 1. In some cases, the medical device system 200 can be incorporated into an Internet of Things that includes wearable smart technology. Such wearable smart technology can include, for example, a watch, a belt, a necklace, earrings, a bracelet, headphones, earphones, or other wearable items.

[0086] Peripheral device 250 may include a UI 252, a memory circuit 254, a processor 256, a wireless communication circuit 258, a sensor 260, or any combination thereof. Peripheral device 250 may not necessarily include all of the components shown in Figure 2. Peripheral device 250 may also include a power source, such as a battery.

[0087] The UI 252 can be provided, for example, using any suitable input / output device of the peripheral device 250, such as a touch screen interface, a microphone (e.g., for receiving voice commands), or a speaker, a vibrating circuit, or any combination thereof. The UI 252 can receive information (e.g., instructions, glucose values) from a host or another user. The UI 252 can also deliver information to the host or other user, for example, by displaying UI elements on the UI 252. For example, the UI elements can show glucose or other analyte concentration values, glucose or other analyte trends, glucose or other analyte alerts, etc. Trends can be shown with UI elements such as arrows, graphs, charts, etc.

[0088] The processor 256 can be configured to present information to or receive input from a user via the UI 252. The processor 256 can also be configured to store and retrieve information, such as communication information (e.g., pairing information or data center access information), user information, sensor data, or trends, in the memory circuit 254. The wireless communication circuit 258 can include a transceiver and an antenna configured to communicate via a wireless protocol, such as any of the wireless protocols described herein. The sensors 260 can include, for example, an accelerometer, a temperature sensor, a location sensor, a biosensor, or a blood glucose sensor, a blood pressure sensor, a heart rate sensor, a respiration sensor, or another physiological sensor.

[0089] The peripheral devices 250 can be configured to receive and display sensor information that may be transmitted by the sensor electronics 106 (e.g., in a customized data package transmitted to a display device based on respective preferences). The sensor information (e.g., blood glucose concentration level) or alerts or notifications (e.g., “high glucose level”, “low glucose level”, or “decline rate alert”) may be communicated via the UI 252 (e.g., via a visual display, sound, or vibration). In some examples, the peripheral devices 250 can be configured to display or otherwise communicate the sensor information communicated from the sensor electronics 106 (e.g., in a data package transmitted to a respective display device). For example, the peripheral devices 250 can transmit processed data (e.g., an estimated analyte concentration value that may be determined by processing raw sensor data), such that a device receiving the data may not be required to further process the data to determine usable information (such as an estimated analyte concentration value). In other examples, the peripheral devices 250 can process or interpret the received information (e.g., to issue an alert based on glucose values ​​or glucose trends). In various embodiments, the peripheral device 250 can receive information directly from the sensor electronics 106 or over a network (e.g., via a cellular or Wi-Fi network that receives information from the sensor electronics 106 or from a device that is communicatively coupled to the sensor electronics 106).

[0090] 2, medical device system 200 can include an optional medical device 270. For example, medical device 270 can be used in addition to or instead of peripheral device 250. Medical device 270 can be or include any suitable type of medical or other computing device, including, for example, medical device 108, peripheral medical device 122, wearable device 120, wearable sensor 130, or wearable sensor 136 shown in FIG. 1. Medical device 270 can include a UI 272, a memory circuit 274, a processor 276, a wireless communication circuit 278, a sensor 280, a therapy circuit 282, or any combination thereof.

[0091] Like the UI 252, the UI 272 can be provided using any suitable input / output device of the medical device 270, such as a touch screen interface, a microphone or speaker, a vibration circuit, or any combination thereof. The UI 272 can receive information (e.g., glucose values, alert settings, calibration coding) from a host or another user. The UI 272 can also deliver information to the host or other user, such as by displaying UI elements on the UI 252. For example, the UI elements can show glucose or other analyte concentration values, glucose or other analyte trends, glucose or other analyte alerts, etc. Trends can be shown with UI elements such as arrows, graphs, charts, etc.

[0092] The processor 276 may be configured to present information to or receive input from a user via the UI 272. The processor 276 may also be configured to store and retrieve information, such as communication information (e.g., pairing information or data center access information), user information, sensor data, or trends, in the memory circuit 274. The wireless communication circuit 278 may include a transceiver and antenna configured to communicate via a wireless protocol, such as any of the wireless protocols described herein.

[0093] The sensor 280 may include, for example, an accelerometer, a temperature sensor, a position sensor, a biosensor, or a blood glucose sensor, a blood pressure sensor, a heart rate sensor, a respiration sensor, or another physiological sensor. The medical device 270 may include more than one sensor (or memory or other components) although only one sensor 280 is shown in the example of FIG. 2. In various examples, the medical device 270 may be a smart handheld glucose sensor (e.g., a blood glucose meter), a drug pump (e.g., an insulin pump), or other physiological sensor device, a therapy device, or a combination thereof.

[0094] In examples where the medical device 270 may include an insulin pump, the pump and the analyte sensor system 102 may communicate bidirectionally (e.g., the pump may request a change to the analyte transmission protocol, e.g., may request data points or may request data on a more frequent schedule), or the pump and the analyte sensor system 102 may communicate using one-way communication (e.g., the pump may receive analyte concentration level information from the analyte sensor system). In one-way communication, the glucose value may be incorporated into an advertising message, which may be encrypted with a pre-shared key. In two-way communication, the pump may request a value and the analyte sensor system 102 may share or obtain and share that value in response to a request from the pump, any or all of these communications may be encrypted using one or more pre-shared keys. The insulin pump may receive and track analyte (e.g., glucose) values ​​transmitted from the analyte sensor system 102 using one-way communication to the pump for one or more of a variety of reasons. For example, the insulin pump may suspend or activate insulin administration based on glucose values ​​below or above a threshold.

[0095] In some examples, the medical device system 200 can include two or more peripheral devices and / or medical devices, each of which receives information directly or indirectly from the analyte sensor system 102. Because different display devices have different user interfaces, the content of the data package (e.g., the amount, format, and / or type of data displayed, alarms, etc.) can be customized (e.g., programmed differently by the manufacturer and / or end user) for each particular device. For example, referring now to the example of FIG. 1, multiple different peripheral devices can wirelessly communicate directly with the sensor electronics 106 (e.g., on-skin sensor electronics 106 physically connected to the continuous analyte sensor 104, etc.) during a sensor session to enable multiple different types and / or levels of display and / or functionality related to the displayable sensor information or to conserve battery power of the analyte sensor system 102, and one or more designated devices can communicate with the analyte sensor system 102 to relay (i.e., share) information to other devices, either directly or via a server system (e.g., a networked data center) 126.

[0096] Analyte Sensor Membrane FIG. 3A is a side view illustrating an exemplary analyte sensor 334 that can be implanted in a host. The mounting unit 314 can be adhered to the skin of the host using an adhesive pad 308. The adhesive pad 308 can be formed of a stretchable material and can be removably attached to the skin using an adhesive. The electronics unit 318 can be mechanically coupled to the mounting unit 314. In some embodiments, the electronics unit 318 and the mounting unit 314 are arranged in a manner similar to the sensor electronics 106 and the sensor mounting unit 290 shown in FIGS. 1 and 2. In some cases, the analyte sensor 334 does not include a separate mounting unit. In some cases, the analyte sensor 334 can be an integrated package. The analyte sensor 334 can be a coaxial sensor configuration. In other embodiments, the analyte sensor 334 can be a planar configuration.

[0097] Figure 3B is a cross-sectional view of the sensor of Figure 3A along section line BB when the sensor is configured in a coaxial configuration. Figure 3B shows the exposed electroactive surface of at least the working electrode 338 surrounded by the sensing membrane. In general, the sensing membrane of the present disclosure includes multiple domains or layers, e.g., an interference domain 344, an enzyme domain 346, and a resistance domain 348, and may include additional domains, such as an electrode domain, a cell impermeable domain (not shown), an oxygen domain (not shown), a drug releasing membrane 370, and / or a biointerface membrane (not shown), as described in more detail below and / or in the co-pending U.S. patent applications cited herein. However, it is understood that sensing membranes modified for other sensors, e.g., by including fewer or additional domains, are within the scope of the present disclosure.

[0098] A cross-sectional view of a planar version of the sensor is shown in Figure 3C. Figure 3C shows the exposed electroactive surface of at least the working electrode 380 surrounded by a sensing membrane. Similar to the circular sensor shown in Figure 3B, the planar version can include a sensing membrane with multiple layers or domains. For example, the planar version can include an interference domain 382, ​​an enzyme domain 384, and a resistance domain 386 in addition to other variations of the domains (e.g., a drug-releasing membrane 388 as discussed above).

[0099] In some embodiments, one or more domains of the sensing membrane are formed from materials such as silicone, polytetrafluoroethylene, ethylene tetrafluoroethylene copolymers, polyolefins, polyesters, polycarbonates, biostable polytetrafluoroethylene, homopolymers, copolymers, terpolymers of polyurethane, polypropylene (PP), polyvinylchloride (PVC), polyvinylidene fluoride (PVDF), polybutylene terephthalate (PBT), polymethylmethacrylate (PMMA), polyether ether ketone (PEEK), polyurethanes, cellulosic polymers, poly(ethylene oxide), poly(propylene oxide), and copolymers and blends thereof, polysulfones, and block copolymers thereof (e.g., diblock, triblock, alternating, random, and graft copolymers, etc.). Co-pending US patent application Ser. No. 10 / 838,912, which is incorporated herein by reference in its entirety, describes biological interfaces and sensing membrane configurations and materials that may be applied to the sensors of the present disclosure.

[0100] The sensing membrane can be deposited on the electroactive surface of the electrode material using known thin or thick film techniques (e.g., spraying, electrodeposition, dipping, etc.). It should be noted that the sensing membrane surrounding the working electrode does not have to be of the same structure as the sensing membrane surrounding the reference electrode, etc. For example, an enzyme domain deposited on the working electrode does not necessarily have to be deposited on the reference electrode and / or counter electrode. Depending on the embodiment, the sensor core including the electrodes and / or the membrane system can be formed in various ways. Examples of methods for forming the sensors, membrane systems, and sensor systems discussed herein can be found in currently pending U.S. patent application Ser. No. 16 / 452,364 to Boock et al., which is incorporated herein by reference in its entirety.

[0101] In the illustrated embodiment, the sensor is an enzyme-based electrochemical sensor, and the working electrode 338 measures products (including but not limited to hydrogen peroxide) generated by the enzyme-catalyzed reaction of glucose. In some cases, a non-enzyme-based sensor, such as an oxygen sensor, can be used. The detected products create a measurable electronic current, as described in more detail above and understood by those skilled in the art (e.g., detection of glucose utilizing glucose oxidase produces hydrogen peroxide as a by-product, and H2O2 reacts with the surface of the working electrode to produce two protons (2H+), two electrons (2e-), and one oxygen molecule (O2), which produces the detected electronic current). Preferably, one or more potentiostats are used to monitor the electrochemical reaction at the electroactive surface of the working electrode. The potentiostat applies a constant potential to the working electrode and its associated reference electrode to determine the current generated at the working electrode. The current generated at the working electrode 338 (and flows through the circuit to the counter electrode) is substantially proportional to the amount of H2O2 that diffuses to the working electrode. The output signal is typically a raw data stream that is used to provide a useful value of, for example, the measured analyte concentration in the host to a host or physician.

[0102] Some alternative analyte sensors that can benefit from the systems and methods of the present disclosure are described, for example, in U.S. Pat. No. 5,711,861 to Ward et al., U.S. Pat. No. 6,642,015 to Vachon et al., U.S. Pat. No. 6,654,625 to Say et al., U.S. Pat. No. 6,565,509 to Say et al., U.S. Pat. No. 6,514,718 to Heller, U.S. Pat. No. 6,465,066 to Essenpreis et al., U.S. Pat. No. 6,465,066 to Offenbacher et al., and U.S. Pat. No. 6,214,185 to Cunningham et al., U.S. Patent No. 5,310,469 to Shaffer et al., U.S. Patent No. 5,683,562 to Bonnecaze et al., U.S. Patent No. 6,579,690 to Bonnecaze et al., U.S. Patent No. 6,484,046 to Say et al., U.S. Patent No. 6,512,939 to Colvin et al., U.S. Patent No. 6,424,847 to Mastrototaro et al., and U.S. Patent No. 6,424,847 to Mastrototaro et al., all of which are incorporated herein by reference in their entireties and are not intended to be exhaustive of all applicable analyte sensors, although it should be understood that in general, the disclosed embodiments are applicable to a variety of analyte sensor configurations.

[0103] 3C is a cross-sectional view of the sensor of FIG. 3A along section line CC, showing the unexposed electroactive surface of at least the working electrode 338 surrounded by a sensing membrane including multiple domains or layers, e.g., interference domain 344, enzyme domain 346, and resistive domain 348, which may include additional domains / membranes, such as an electrode domain, a cell impermeable domain (not shown), an oxygen domain (not shown), a drug releasing membrane 370, and / or a biointerface membrane 368 (not shown), as described in more detail below. As shown in FIG. 3C, the drug releasing membrane 370 is positioned adjacent to the working electrode 338 surface and does not cover the working electrode 338 or multiple domains or layers, e.g., interference domain 344, enzyme domain 346, and resistive domain 348, of the sensing membrane 332. In one example, the drug releasing membrane 370 is positioned at the distal end 337 of the analyte sensor 334. In another embodiment, the drug releasing membrane 370 spans the electroactive portion of the working electrode 338 and does not cover the sensing membrane 332 associated with the working electrode 338 .

[0104] Figures 3A-3C depict cross-sections of circular or coaxial sensors in embodiments. Similar membranes can be applied to exemplary planar analyte sensors as discussed below with reference to Figures 4A-8F. The sensing membrane in the exemplary planar analyte sensors can contain the same or similar components as the membranes discussed with reference to Figures 3A-3C.

[0105] Planar Analyte Sensors 4A-8F depict schematic diagrams of planar analyte sensors. Each of the planar analyte sensors discussed herein can be configured to measure the concentration of one or more analytes. Planar analyte sensors can be easily manufactured and can produce reproducible results. Planar analyte sensors can be configured to monitor at least one analyte, including in some examples sequentially monitoring two or more analytes. Planar analyte sensors can be configured differently and can be described based on the geometry of their electrode layout. Sensor types can include single-sided or double-sided layouts. In single-sided layouts, the electrodes can be conductive traces and can be in a coplanar arrangement, a stacked arrangement, or a staggered arrangement. In double-sided layouts, the electrodes can be in a coplanar arrangement (aligned along a shared plane in a single layer along each substrate side), a stacked arrangement (aligned along a shared plane perpendicular to the substrate side), or a staggered arrangement (offset along or above a plane or axis), as well as an arrangement with connector pads on one side of the sensor, or an arrangement with connector pads on both sides of the sensor.

[0106] 4A-4G illustrate a single-sided, coplanar analyte sensor assembly 400, according to an embodiment. The sensor assembly can have a first end 412 and a second end 414. The sensor assembly 400 can include a substrate 410, conductive traces 421, connector pads 422, a working electrode 424, a counter electrode 426, an insulator 430, and a reference electrode 440. In the sensor assembly 400, a single-sided, planar configuration is used. In the sensor assembly 400, a three-electrode sensor is shown having a working electrode (WE) 424, a counter electrode (CE) 426, and a reference electrode (RE) 440. In the sensor assembly 400, the electrodes are on the same plane. In one or more implementations, the underlay configuration of the single-sided coplanar analyte sensor assembly 400 or other sensor assemblies as discussed herein may allow one or more of the reference electrodes (e.g., 440) or counter electrodes (e.g., 426) to be moved away from the sensor assembly 400 or other sensor assemblies as discussed herein to a location outside the body (e.g., as part of the wearable 120 or other wearable device as discussed herein) rather than being deployed subcutaneously. This has the advantage of freeing up space within the host (e.g., within a wound pocket into which the sensor assembly 400 is inserted) in which the single-sided coplanar analyte sensor assembly 400 or other sensor assemblies are deployed for additional working electrodes and / or to detect additional analytes.

[0107] Furthermore, by configuring the wearable 120, or other wearable devices discussed herein, to include a reference electrode (440) and a counter electrode (426), the amount of material inserted into the body such that the electrodes are deployed externally is limited. As a result, the host's foreign body response, e.g., the host's immune system response, may be reduced. In one or more configurations, for example, the reference electrode (440) may include or be otherwise formed from silver chloride (AgCl). However, some hosts may have sensitivity issues with silver chloride. Thus, configuring the wearable 120, or other wearable devices discussed herein, to include a reference electrode (440), rather than incorporating the reference electrode (440) as part of the in vivo portion of the sensor assembly discussed herein, may reduce the immune response of such hosts, such as reducing eye and / or skin irritation.

[0108] 4A-4D depict top schematic views of the resulting sensor assembly 400. FIGS. 4E-4G depict cross-sectional schematic views of the sensor assembly 400 at various points along the length of the sensor assembly 400.

[0109] The sensor assembly 400 may extend between a first end 412 and a second end 414 and may be substantially planar along its length as measured from the first end 412 to the second end 414. The first end 412 may be a connection end, such as to enable electrical connection of the sensor assembly 400 to a reader, computer, or other component for interpreting signals detected by the sensor assembly 400. The first end 412 may house one or more connection pads 422.

[0110] The second end 414 may be a sensing end for connection to or implantation into a patient, such as, for example, to detect glucose or other analytes. The second end 414 may house the electrodes 424, 426, and 440. The second end 414 may be an implantable portion of the sensor assembly 400. The first end 412 of the sensor having the connector pads 422 may be a proximal end of the sensor assembly 400. The second end 414 having the implantable portion of the sensor containing the sensing electrodes may be a distal end of the sensor assembly 400.

[0111] As shown in FIG. 4A, the substrate 410 can extend between a first end 412 and a second end 414. The substrate 410 can be a relatively planar material, for example, the substrate 410 can be a thin flexible layer for housing other components. In some cases, the substrate 410 can be a polymer film, such as a liquid crystal polymer (LCP), polyimide (PI), polyethylene terephthalate (PET), combinations thereof, or similar polymer films. The substrate 410 can have a thickness of about 25 to about 450 μm, such as a thickness of about 75 to 100 μm. In some embodiments, a substrate thickness of about 40 μm to about 80 μm can be used.

[0112] The conductive traces 421, connector pads 422, working electrodes 424, and counter electrodes 426 can be made of a conductive layer 420 built on a substrate. The connector pads 422 can be located on or at the first end 412 of the assembly 400 and allow for electrical connection of the sensor assembly 400. The working electrodes 424 and counter electrodes 426 can be sensing electrodes exposed at the second end 414 of the assembly 400 for implantation and sensing of an analyte in a patient environment. The conductive traces 421 can connect the electrodes 424, 426 to the connector pads 422.

[0113] As shown in FIG. 4B, the conductive layer 420 can be constructed on the substrate 410 with the conductive traces 421, connector pads 422, working electrode 424, and counter electrode 426 in a single plane or layer. The conductive layer 420 can be made of sputtered metal, such as a sputtered metal layer of titanium / gold / platinum or platinum / gold / platinum. In this case, the associated sensing surface, such as the working electrode 424, can have platinum exposed for electrical connection and sensing. The reference electrode 440 can be deposited on the base metal pad and can be connected via an additional conductive trace.

[0114] In some embodiments, the conductive layer 420 is formed from a single conductor, such as gold or platinum. In other embodiments, the conductive layer 420 can be formed from two or more materials, such as a thin palladium layer covered with gold and platinum. The composition, geometry, and exposed conductor surface can depend on the fabrication method, the desired mechanical properties, and the requirements of the sensing chemistry. For example, the base conductive material can be formed by a cheaper material, such as silver, which is covered with platinum in strategic locations for the active sensing surface. In some cases, gold can be plated as the base conductor, which can be covered with platinum to provide both mechanical robustness and an active sensing surface for sensing hydrogen peroxide.

[0115] The conductive layer 420, including the working electrode 424, counter electrode 426, connector pad 422, and conductive traces 421, can be formed by a variety of techniques, such as plating, sputtering, or printing. Standard photolithography techniques, laser ablation, or printing (e.g., inkjet or screen printing) can be used to form the patterned structures of the conductive layer.

[0116] While specific electrode designations are shown in the supporting documentation, it should be understood that size, shape, and electrode identity can vary depending on the specific use case, such as the specific analyte to be determined. Typical size and shape of the sensor is 3mm-4mm wide at the proximal end (connector end) and 300-500μm wide at the narrow implantable distal end. Overall length of the sensor is generally 15mm-25mm depending on wearer / inserter requirements.

[0117] As shown in FIG. 4C, an insulator 430 can be layered on top of the conductive layer 420 if desired. The insulating material can be referred to as a "solder mask," "dielectric," or "insulator." These materials can be used to protect the conductive traces from exposure to the sample matrix and environment, as well as to improve the accuracy and reliability of the measurement by defining the sensing electrode area. An opening 431 can be created for later deposition of a reference electrode 440.

[0118] Here, the insulator 430 can be made of an electrically insulating material deposited on top of the conductive layer to protect the conductive traces 421 and define openings for the connector pads 422 and electrodes 424, 426, as well as an opening 431 for the reference electrode 440. The insulator 430 can be, for example, a thin layer of solder mask.

[0119] As shown in FIG. 4D, the reference electrode 440 material can be deposited over a designated reference electrode opening in the insulator 430. The reference electrode 440 material can be, for example, a silver / silver chloride blend. It can be deposited over a designated sensing electrode pad. This reference electrode material can be deposited by a printing technique, such as screen printing, or by individual dispensing, such as with a jet valve dispensing device.

[0120] 4E-4G depict cross sections of the assembly 400 at various points along the body of the assembly. FIG. 4E shows a cross section at section line EE of FIG. 4D at a central portion of the assembly 400. In this portion of the assembly 400, the conductive trace 421 is visible between the insulator 430 and the substrate 410. FIG. 4F shows a cross section at section line FF of FIG. 4D near the second end 414 of the assembly 400. In this portion of the assembly 400, the reference electrode 440 is visible on top of the conductive trace 421. FIG. 4G depicts a cross section at section line GG of the assembly near the second end 414. Here, the working electrode 424 is visible. The assembly 400 is a single-sided, flush arrangement for the electrodes 424, 426, 440.

[0121] 5A-5K illustrate a single-sided stacked analyte sensor assembly 500, according to an embodiment. Sensor assembly 500 is similar to assembly 400, but the stacked version of assembly 500 includes multiple insulating and electrode layers on top of a substrate. Sensor assembly 500 can include components similar to those of assembly 400 discussed above, except where noted otherwise.

[0122] 5A-5G depict schematic top views of various layers of assembly 500. FIGS. 5H-5K depict schematic cross-sectional views of the entire sensor assembly 500.

[0123] The sensor assembly 500 can have a first end 512 and a second end 514. The sensor assembly 500 can include a substrate 510, conductive layers 516, 517, 518, conductive traces 520, 521, 522, connector pads 523, 524, 525, a working electrode 526, a counter electrode 527, insulating layers 530, 532, 534, and a reference electrode 540. In the sensor assembly 500, a single-sided stacking configuration is used. In the sensor assembly 500, a three-electrode sensor is shown having a working electrode (WE) 526, a counter electrode (CE) 527, and a reference electrode (RE) 540. In the sensor assembly 500, the electrodes are stacked or staggered and geometrically offset from each other along the z-axis.

[0124] In the sensor assembly 500, instead of the coplanar arrangement discussed above, multiple conductive layers 516, 517, 518 and insulating layers 530, 532, 534 are stacked. The conductive layers 516, 517, 518 may be staggered for designated exposure of the electrodes 526, 527, 540 and connector pads 523, 524, 525.

[0125] As shown in FIG. 5B, a first conductive layer 516 can be deposited on the substrate 510 to form a first conductive trace 520, a first sensing electrode 526, and a first connector pad 524. As shown in FIG. 5C, a first insulating layer 530 can be deposited on top of the first conductive trace 520, leaving the first sensing electrode 526 and the first connector pad 524 exposed. In an embodiment, the first conductive layer 516 on the polymer substrate 510 can be printed from a conductive ink. In some embodiments, the first conductive layer 516, or other conductive layers discussed herein, carbon conductive inks may be suitable for use in biosensor applications. In other embodiments, other inks including precious metals may be used to form one or more conductive layers discussed herein, including the layers discussed in FIGS. 5A-5K.

[0126] 5D, a second conductive layer 517 can be deposited over the first insulating layer 530 to form the second conductive trace 521, the second sensing electrode 527, and the second connector pad 525. The second conductive layer 517 can be printed from the same or a different conductive ink as used for the first conductive layer 516, for example, a platinum ink suitable for biosensor applications. A second insulating layer 532 can be deposited over the second conductive layer 517, leaving openings 591, 593 for the second sensing electrode 527 and the second connector pad 525.

[0127] In some cases, this process can be repeated to form additional sensing electrodes and corresponding layers of conductive and insulating materials. In assembly 500, a third conductive layer 518 and a third insulating layer 534 are added in Figures 5F and 5G. In an embodiment, third conductive layer 518 can be made of a silver / silver chloride ink deposited on top of second insulating layer 532 to form reference electrode 540. However, additional layers can be added as desired.

[0128] Figures 5H, 5I, and 5J depict cross-sectional views of the assembly 500 at various points along its length. In Figure 5H, a closer cross-sectional view of the conductive traces 520, 521, 522 and interspersed insulating layers 530, 532, 534 can be seen between the first end 512 and the second end 514. Further along the length of the assembly 500, a cross-sectional view of the assembly 500 with electrodes 526, 527 can be seen in Figure 5I. The cross-sectional view in Figure 5J is further toward the second end 514.

[0129] FIG. 5K depicts a side view of the second end 514 of the assembly 500. The view of FIG. 5K shows the sensing end of the assembly 500 and serves to illustrate the stepped cross-section of such a stacked arrangement. Similar to the views referred to above, the view of FIG. 5K depicts the substrate 510 on which the electrodes 526, 527, 540 are stacked and interspersed with insulating layers 530, 531, 532 such that the electrodes 526, 527, 540 are exposed at various lengths away from the second end 514.

[0130] 6A-6E illustrate a double-sided, coplanar, non-connected analyte sensor assembly 600, according to an embodiment. Sensor assembly 600 is similar to assembly 400, but the double-sided version of sensor assembly 600 includes two sides on a substrate. Sensor assembly 600 can include components similar to those of assembly 400 discussed above, except where noted otherwise.

[0131] 6A-6B depict schematic top views of opposing sides of the sensor assembly 600. Figures 6C-6E depict schematic cross-sectional views of the entire sensor assembly 600.

[0132] The sensor assembly 600 can have a first side 602 and a second side 604 opposite the first side, in addition to a first end 612 and a second end 614. The sensor assembly 600 can include a substrate 610, conductive traces 620, 621, connector pads 622, 623, working electrodes 624, 625, a counter electrode 626, insulating layers 630, 632, and a reference electrode 640. In the sensor assembly 600, a double-sided planar configuration is used. In the sensor assembly 600, a multi-electrode sensor is shown having two working electrodes (WE) 624, 625, a counter electrode (CE) 626, and a reference electrode (RE) 640. In the sensor assembly 600, the electrodes are on the same plane. The sensor assembly 600 is an unconnected variation.

[0133] In the sensor assembly 600, structures can be formed on both sides 602, 604 of the substrate 610. For example, connector pads 622, 623 can be formed on opposing sides 602, 604, respectively. This can allow for connections to the sensing electronics from both sides of the sensor assembly 600. Similarly, conductive traces 620, 621 can be formed on both sides 602, 604 of the sensor assembly 600. On each respective side 602, 604, the conductive traces 620, 621 can be coplanar with one another.

[0134] An insulating layer 630, 632, such as a solder mask or other insulating material, can be deposited over the conductive layer including the conductive traces 620, 621. Openings can be formed in the insulating layers 630, 632 to form the working electrodes 624, 625 and the counter electrode 626. Openings can be left for the reference electrode 640. A reference electrode material, such as silver / silver chloride, can be deposited on the designated sensing surface for the reference electrode 640. The insulating material can include epoxy, polyimide, polyurethane, polyethylene, or other materials or combinations of materials.

[0135] 6A-6E, a double-sided sensor assembly 600 can include a first working electrode 624, a second working electrode 625, a counter electrode 626, and a reference electrode 640. In some cases, such a double-sided sensor can contain more or fewer electrodes. For example, a double-sided sensor can include a single working electrode and a reference electrode.

[0136] 6C-6E depict a cross section of the sensor assembly 600. Shown in FIG. 6C is a cross section along section line CC, where the substrate 610 is located between two insulating layers 630, 632. The substrate 610 can be, for example, about 50 microns thick. Conductive traces 620, 621 can be seen. On the first side 602, three conductive traces 620 extend along the length of the sensor assembly 600, each connecting to a connector pad 622. The conductive traces 621 on the second side 604 can be connected to a connector pad 623.

[0137] In Figure 6D, the cross section is taken along section line DD. The reference electrode 640 is now visible. In Figure 6E, the cross section is taken along section line EE, and both working electrodes 624, 625 are visible on opposite sides 602, 604 of the sensor assembly 600.

[0138] 7A-7E illustrate a double-sided coplanar analyte sensor assembly 700, according to an embodiment. Sensor assembly 700 is similar to assembly 400, but the double-sided version of assembly 700 includes two sides on a substrate. Sensor assembly 700 can include components similar to those of assembly 400 discussed above, except where noted otherwise.

[0139] 7A-7B depict schematic top views of opposing sides of assembly 700. Figures 7C-7E depict schematic cross-sectional views of the entire sensor assembly 700. In some cases, sensor assembly 700 can include chamfered ends, rounded ends, flat ends, or other suitable shapes.

[0140] The sensor assembly 700 can have a first side 702 and a second side 704 opposite the first side, in addition to a first end 712 and a second end 714. The sensor assembly 700 can include a substrate 710, conductive traces 720, 721, a connector pad 722, working electrodes 724, 725, a counter electrode 726, an insulating layer 730, 732, and a reference electrode 740. In the sensor assembly 700, a double-sided planar configuration is used. In the sensor assembly 700, a multi-electrode sensor is shown having two working electrodes (WE) 724, 725, a counter electrode (CE) 726, and a reference electrode (RE) 740. In the sensor assembly 700, the electrodes are coplanar. The assembly 700 is a coplanar connected variant.

[0141] In the sensor assembly 700, a substrate 710 is located between two sides 702, 704, which may each house several coplanar components. For example, a coplanar conductive trace 720 may be on a first side 702, and a second conductive trace 721 may be on a second side 704. Each side 702, 704 may be covered by an insulating layer 730, 732. The insulating layers 730, 732 may define areas for the electrodes 724, 725, 726, and a reference electrode 740.

[0142] The assembly 700 may also include vias that can provide electrical connections between the two sides 702, 704 of the sensor assembly 700. Including vias allows for connection to the sensing electronics through the connector pads 722 on a single side 702 of the sensor, as well as wiring traces to new locations and may allow flexible geometries to be used. The vias may be formed from a variety of conductive materials discussed herein, including carbon, graphitic carbon, Pt, or combinations including Pt and C, Au and C. In some examples, the conductive material forming the vias between the sides 702, 704 of the assembly or other assemblies as discussed herein may or may not further include conductive nanoparticles.

[0143] As shown in Figures 7A-7E, the assembly 700 can include four connector pads 722 on a first side 702 that can be electrically coupled to electrodes 725, 740 on a second side 704 by vias and traces. In some cases, the WE, RE, and CE can be located on the opposite side of the sensor assembly 700 relative to the connector pads 722. In some cases, as shown in the assembly 700, the first working electrode 724 and the counter electrode 726 can be located on the first side 702 of the sensor, while the second working electrode 725 and the reference electrode 740 can be located on the other side 704 of the sensor. Because the connector pads 722 for connecting to the sensing electronics are located on only one side, vias can be used to establish electrical contact between the traces and pads on both sides 702, 704 of the sensor assembly 700.

[0144] Sensor assembly 800 is similar to assembly 700, except that the double-sided version of assembly 800 includes two sides on a substrate. Sensor assembly 800 can include components similar to those of assembly 500 discussed above, except where otherwise noted.

[0145] The sensor assembly 800 can have a first side 802 and a second side 804 opposite the first side, in addition to a first end 812 and a second end 814. The sensor assembly 800 can include a substrate 810, conductive traces 820, 821, a connector pad 822, working electrodes 824, 825, a counter electrode 826, insulating layers 830, 832, and a reference electrode 840. In the sensor assembly 800, a double-sided stacking configuration is used. In the sensor assembly 800, a multi-electrode sensor is shown having two working electrodes (WE) 824, 825, a counter electrode (CE) 826, and a reference electrode (RE) 840. In the sensor assembly 800, the electrodes are staggered.

[0146] Sensor assembly 800 is similar to assembly 400 above, but has two sides. Figures 8A-8F illustrate a double-sided analyte sensor assembly 800, according to an embodiment. Figures 8A-8C depict the various layers of a first side 802, and Figures 8D-8F depict the various layers of a second side 804.

[0147] Figure 8A depicts a substrate 810 on a first side 802. Figure 8B depicts the deposition of a conductive layer onto the substrate to form a connector pad 822, a conductive trace 820, a first working electrode 824, and a counter electrode 826. Figure 8C depicts the deposition of an insulating layer 830 onto the first side 802.

[0148] Figure 8D depicts the substrate 810 on the second side 804. Figure 8E depicts the deposition of a conductive layer onto the substrate to form a conductive trace 821 and a second working electrode 825. Figure 8E depicts the construction of a second insulating layer 832 and a reference electrode 840.

[0149] 9-14 illustrate various embodiments of methods for manufacturing planar sensor assemblies, such as sensor assemblies 500-800 discussed above.

[0150] 9 illustrates a schematic diagram of a system 900 for fabricating a coplanar analyte sensor assembly, according to an embodiment. The system 900 can use various components including layer spools 910, 912, 914, 916, a lamination tool 920, a laser skiving station 930, an electroplating bath 940, and a rotogravure 950. In other embodiments, the electrodes discussed herein can be formed via a microdispensing operation (not shown here) followed by laser skiving at station 930. In this embodiment, the microdispensing operation can be followed by laser singulation as discussed herein.

[0151] In the example of Figure 9, the components may move from left to right. The generation may be continuous and scalable.

[0152] Initially, layer spools 910, 912, 914, 916 are provided to the system 900. The first spool 910 can include a substrate, such as the thin polymer substrate discussed above. The second spool 912 can include, for example, a first conductive layer, a first insulating layer, and an adhesive. The third spool 914 can include a second conductive layer, a second insulating layer, and an adhesive. The fourth spool 916 can include a third conductive layer, a third insulating layer, and an adhesive.

[0153] The spools 910, 912, 914, 916 can be aligned to alternate conductive and insulating layers. The spools 910, 912, 914, 916 can be fed into the system 900 and into a lamination tool 920 where the layers can be laminated together to produce a planar sheet having multiple layers fed through a production line. In some examples, the conductive layer formed through the lamination operation can be formed using a thin metal foil. The thin metal foils discussed herein can vary in thickness depending on the application and the equipment used to perform the lamination operation. The thin metal foils can include nickel, titanium, gold, platinum, or alloys or combinations thereof. In other examples, the conductive layer formed through the lamination operation discussed herein can include a conductive material deposited on a thin polymer layer. Depending on the example, the conductive material can include carbon nanotubes or nanoparticles, polyaniline, or poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS).

[0154] In other embodiments, the third spool 914 includes another substrate in addition to or in place of the second conductive layer, the second insulating layer, and the adhesive, which may or may not be of the same composition and thickness as the substrate of the first spool 910.

[0155] The planar sheet can continue along the production line to a laser skiving station 930, where one or more lasers can be used to open contact pads and electrodes in the sensors. Additionally, the planar sheet can be cut and singulated (e.g., a singulation operation is performed) to produce individual sensor assemblies.

[0156] Optionally, the singulated sensor assemblies can be passed through an electroplating bath 940 to allow for electrode metallization. In some cases, the singulated sensor assemblies can be passed through a rotogravure 950 to allow for reference electrode deposition. In some cases, a separate dispense method or slot die coating can be used instead of or in addition to the above.

[0157] 10A and 10B illustrate a method of making a multi-layer coplanar analyte sensor assembly, according to an embodiment. As shown in FIG. 10A, a plurality of individual sensor assemblies 1000 are produced together on a production line in a sheet 1001, such as by the method discussed above with reference to FIG. 9. The sheet 1001 can be moved along the production line and the individual sensor assemblies 1000 can be separated, such as by skiving or other cutting methods.

[0158] 11A-11C illustrate a method of making a coplanar analyte sensor assembly 1100, according to an embodiment. As shown in FIG. 11A, on a substrate 1110, electrodes 1124, 1126, and 1140 can be layered in a stack, alternating with insulating layers 1130, 1132, 1133. The layers can be, for example, laminated together.

[0159] As shown in Figure 1 IB, multiple sensor assemblies can be on a supply planar sheet 1101 moving along an assembly line, where individual sensor assembly electrodes can be released and electrodeposition can occur as desired (1105). Individual assemblies can be separated, such as by laser skiving.

[0160] 11C, a completed individual assembly 1100 can include a first electrode 1124, a second electrode 1126, and a third electrode 1140 stacked on top of each other and separated by insulating layers 1130, 1132, 1134. The assembly 1100 can be contained by a substrate 1110.

[0161] 12 illustrates a method 1200 of making a coplanar analyte sensor assembly, according to an embodiment. In operation 1210, a substrate 1206, a first adhesive layer 1204, and a first electrode 1202 can be laminated together. Then, in operation 1220, the electrode can be exposed, such as by laser skiving. In operation 1230, a second insulating layer can be applied and laminated over the first electrode 1202 along with a top layer. The assembly can be further skived in operation 1240 to expose the electrode 1226.

[0162] 13 illustrates a method 1300 of making a coplanar analyte sensor assembly, according to an embodiment. In method 1300, an electrode 1302 can be layered and laminated (operation 1350) with an adhesion layer 1304 and a substrate layer 1306. In contrast to method 1200, operation 1350 can be performed all at once with more layers. Then, in step 1360, the electrode can be exposed, such as through skiving or other concrete removal of material.

[0163] 14A-14D illustrate a method of making a skived coplanar analyte sensor assembly, according to an embodiment. The planar sheet 1401 shown in FIG. 14A can be produced by any of the methods discussed above. The planar sheet 1401 can house multiple sensor assemblies 1400. These can be separated into individual assemblies 1400, such as by skiving or other separation methods.

[0164] As shown in Figures 14B-14D, each individual sensor assembly 1400 can include a first end 1412 and a second end 1414. At the first end 1412, various connector pads 1422 can be opened, such as by skiving, to allow for electrical connection. Similarly, at the second end, electrodes 1424, 1426, and 1440 can be opened, such as by skiving, to allow for sensing.

[0165] Coaxial Analyte Sensor 15A-20B depict exemplary coaxial sensor assemblies. For each of these examples, the sensor substrate can be cylindrical and can be manufactured at least in part through one or more extrusion operations. Multiple coating layers can be used with these sensors in the sensing region to enable proper functioning of the sensor itself. In some cases, selective sensing chemicals can be used to coat the sensing region. These chemicals can include, for example, enzymes, mediators, or layers, such as to prevent interference from highly charged small molecules. Such layers can also limit the flux of analytes to the sensor. As discussed in more detail below, these layers can be applied using a variety of methods, such as individual dispensing, spray coating, dip coating, or other methods. Various electrode configurations can be discussed herein.

[0166] Each of the coaxial sensor assemblies discussed below may have a diameter of about 100 micrometers (micrometer, μm) to about 300 micrometers in some cases. In some cases, narrower diameters may be used. In some cases, wider diameters may be used. The sensor assemblies may be of various lengths depending on the desired embedment / insertion depth and the particular sensor connections. The coaxial sensor assemblies may include, for example, a two-electrode configuration or a three-electrode configuration. The sensor substrate may be singulated into individual sensors prior to application of the coating layer. In an embodiment, the coaxial sensor assembly may include a substrate including a cylindrical member having a central axis surrounded by a plurality of concentric circles of increasing radius, the concentric circles being visible through a cross section of the substrate. In some cases, the electrodes may include a cylindrical shell extending along the concentric circles. In some cases, the electrodes may include wires extending along one of the plurality of concentric circles offset from one another by a non-zero angle. In some cases, the electrodes may be nested within one another.

[0167] 15A-15D illustrate a coaxial analyte sensor assembly 1500, according to an embodiment. The sensor assembly 1500 can include a substrate 1510, a first electrode 1520, a second electrode 1530, a third electrode 1540, and a fourth electrode 1550. In one embodiment, the electrodes (1520, 1530, 1540, 1550) can be configured as a counter electrode 1520, a reference electrode 1530, a first working electrode 1540, and a second working electrode 1550. In another embodiment, the electrodes (1520, 1530, 1540, 1550) can be configured as a reference electrode 1520, a counter electrode 1530, a first working electrode 1540, and a second working electrode 1550.

[0168] The sensor assembly 1500 can extend from a first end 1502 to a second end. The first end 1502 can be a sensing end, such as for implantation into a patient to sense an analyte therein. The second end can be for electrical connection.

[0169] The substrate 1510 can be an insulating polymer, such as polyurethane or another suitable insulating matrix. The substrate 1510 can accommodate a number of wires extending from a first end 1502 to a second end, each wire corresponding to one of the electrodes. Each of the counter electrode 1520, the reference electrode 1530, the first working electrode 1540, and the second working electrode 1550 can be embedded within the insulating polymer substrate 1510.

[0170] The electrodes 1520, 1530, 1540, 1550 can be made of round wires of a conductive material suitable for electrochemical sensing, such as platinum, gold, silver, silver, or chloride-coated silver. The wires can extend laterally along the polymer substrate 1510. The electrodes 1520, 1530, 1540, 1550 can have sensing regions 1521, 1531, 1541, 1551, respectively, for electrical connection and sensing when the assembly 1500 is connected to a patient to sense an analyte. In the assembly 1500, the electrodes 1520, 1530, 1540, 1550 can be changed or modified to be working, counter, and reference electrodes as desired for a particular use.

[0171] In the embodiment of Figures 15A-15D, the various wires can be patterned around a central axis A in the polymer substrate 1510. In some cases, the patterns can be aligned around concentric circles, a particular axis, a spiral pattern, or other patterns, as desired. The wires of the electrodes 1520, 1530, 1540, 1550 can be patterned coaxially in a manner that allows for orientation-independent connections when the electrodes 1520, 1530, 1540, 1550 are exposed. As shown in Figure 15B, the various types of electrodes can be aligned with concentric circles B, C, D, and E, respectively, forming a pseudo-spiral when viewed in cross section.

[0172] The sensor assembly 1500 can be fabricated by co-extruding a suitable conductive material with an insulating polymer of the substrate. To form the electrodes 1520, 1530, 1540, 1550 and the sensing areas 1521, 1531, 1541, 1551, the insulating material (and conductive material) can be removed in selective areas to expose the particular electrodes, showing the sensing areas 1521, 1531, 1541, 1551. The exposed sensing areas 1521, 1531, 1541, 1551 can be seen in Figures 15C and 15D. Material can be removed to expose the sensing areas of the electrodes 1520, 1530, 1540, 1550, for example, by laser ablation. In the assembly 1500, a stepped structure can be used to expose the sensing areas for the electrodes 1520, 1530, 1540, 1550. In some cases, the sensing tip can take on additional shapes, such as a cone, etc. In some cases, the arrangement of the electrodes 1520, 1530, 1540, 1550 can be altered such that the positions of the electrodes are different.

[0173] 16A-16D illustrate a coaxial analyte sensor assembly 1600 having radial wires in an insulating polymer, according to an embodiment. The sensor assembly 1600 can include a polymer substrate 1610, a first electrode 1620, a second electrode 1630, a third electrode 1640, and a fourth electrode 1650. In one embodiment, the electrodes (1620, 1630, 1640, 1650) can be configured as a counter electrode 1620, a reference electrode 1630, a first working electrode 1640, and a second working electrode 1650. In another embodiment, the electrodes (1620, 1630, 1640, 1650) can be configured as a reference electrode 1620, a counter electrode 1630, a first working electrode 1640, and a second working electrode 1650. The sensor assembly 1600 can extend from a first end 1602 to a second end. The first end 1602 can be a sensing end, such as for implantation into a patient to sense an analyte therein. The second end can be for electrical connection. The components of the assembly 1600 can be similar to the components of the assembly 1500 discussed above, except as otherwise noted.

[0174] In the assembly 1600, the reference electrode 1630 can extend along a central axis A. The reference electrode 1630 can function as the central portion of the assembly 1600. The reference electrode 1630 can include a single wire extruded as the core of the assembly. The working electrodes 1640, 1650 and the counter electrode 1620 can still contain multiple wires patterned around the core reference electrode 1630. The electrodes 1620, 1630, 1640, 1650 can have sensing regions 1621, 1631, 1641, 1651, respectively, for electrical connection and sensing when the assembly 1600 is connected to a patient for sensing an analyte.

[0175] Here, the core reference electrode 1630 can be co-extruded with the working electrodes 1640, 1650, and the counter electrode 1620 into an insulating polymer substrate 1610. The core reference electrode 1630 can be, for example, a silver chloride coated silver wire. The working electrodes 1640, 1650, and the counter electrode 1620 can be made of, for example, platinum or other conductive materials. In some examples, one or more materials used to form the conductive layers discussed herein can include one or more types of conductive nanoparticles. The working electrodes 1640, 1650, and the counter electrode 1620 can be arranged in an arc around the core reference electrode 1630, such as along concentric circles B, C, and D. This can be seen, for example, in the cross-sections of FIGS. 16A and 16B.

[0176] Similar to assembly 1500, sensing areas 1621, 1631, 1641, and 1651 can be exposed by removing insulating substrate 1610 in selected areas. Material can be removed, for example, by laser ablation. Sensing areas 1621, 1631, 1641, and 1651 can be seen in Figures 16C and 16D. As shown in assembly 1600, sensing areas 1621, 1631, 1641, and 1651 can be formed in a stepped structure. In some cases, other patterning can be used and / or the location of the various electrodes can be changed.

[0177] 17A-17D illustrate a coaxial analyte sensor assembly 1700 having radial wire electrodes in an insulating polymer substrate 1710, according to an embodiment. The sensor assembly 1700 can include a polymer substrate 1710, a first electrode 1720, a second electrode 1730, a third electrode 1740, and a fourth electrode 1750. In one embodiment of the coaxial analyte sensor assembly 1700, the electrodes (1720, 1730, 1740, 1750) can be configured as a reference electrode 1720, a counter electrode 1730, a first working electrode 1740, and a second working electrode 1750. In another embodiment, the electrodes (1720, 1730, 1740, 1750) can be configured as a counter electrode 1720, a reference electrode 1730, a first working electrode 1740, and a second working electrode 1750. The electrodes 1720, 1730, 1740, 1750 can have sensing areas 1721, 1731, 1741, 1751, respectively, for electrical connection and sensing when the assembly 1700 is connected to a patient for sensing an analyte. The sensor assembly 1700 can extend from a first end 1702 to a second end. The first end 1702 can be a sensing end, such as for implantation into a patient for sensing an analyte therein. The second end can be for electrical connection. The components of the assembly 1500 can be similar to the components of the assembly 1500 discussed above, except as otherwise described.

[0178] In the assembly 1700, the counter electrode 1720 can be formed differently from the extrusion of the other electrodes 1730, 1740, 1750. The core reference electrode 1720 and working electrodes 1740, 1750 can be made by extrusion, as discussed above with reference to assemblies 1500 and 1600. However, the counter electrode 1720 can be made by coating the insulating polymer substrate 1710 with a conductive formulation or the like over the co-extruded electrodes 1730, 1740, 1750 and substrate 1710. The coating can be done, for example, by die coating, spray coating, pad printing, deposition, or other methods.

[0179] Selected portions of the insulating polymer substrate 1710 can be removed, such as by laser ablation, to form the sensing regions 1731, 1741, 1751. This can be done in a stepped or other shape, such as a cone shape. The electrode arrangement can additionally be varied.

[0180] FIG. 18 illustrates a coaxial analyte sensor assembly 1800 including a wire embedded in a photoresist insulating polymer, according to an embodiment. The assembly 1800 can include a photoresist insulating polymer substrate 1810 having a photoresist portion 1812, and a wire electrode 1820. Shown in FIG. 18 is a method of producing individual sensor assemblies 1801 by operations including an extrusion operation 1830, a UV exposure operation 1840, a resist development operation 1850, and a singulation operation 1860. During production, a UV light 1870 and a slicing tool 1880 can be used. In this concept, a wire electrode 1820 suitable for electrochemical sensing can be co-extruded with a positive photoresist to form an insulating layer.

[0181] Starting from the left side of FIG. 18, a photoresist insulating polymer substrate 1810 can be co-extruded with a wire electrode 1820 in operation 1830. The photoresist insulating polymer substrate 1810 can contain one or more photoresist portions 1812. After extrusion, UV light 1870 can be used to expose the photoresist portions 1812 and remove predetermined portions of the material surrounding the wire electrode 1820. In this case, the extruded photoresist material with the wire electrode 1820 can be exposed to UV light at specific locations to define the sensing electrode area 1822 and the contact area 1824.

[0182] The exposed electrode regions 1822 may then be developed and cured (operation 1850), such as with a hard bake to harden the resist. Individual assemblies 1821 may then be sliced ​​with a mechanical slicing tool 1880 to produce individual sensors.

[0183] 19A and 19B illustrate a coaxial analyte sensor assembly 1900 including a polymer core, according to an embodiment. The sensor assembly 1900 can include a polymer core 1910, conductive layers 1920, 1930, an insulating dielectric layer 1940, and a conductive layer 1950. The conductive layers 1920, 1930 can have sensing regions 1921, 1931, respectively, for electrical connection and sensing as electrodes. The sensor assembly 1900 can extend from a first end 1902 to a second end 1904. The first end 1902 can be a sensing end, such as for implantation into a patient to sense an analyte therein. The second end 1904 can be for electrical connection.

[0184] In the assembly 1900, the polymer core 1910 can be, for example, a flexible polymer core, such as an LCP polymer, extending along a central axis of the assembly 1900. Here, the flexible polymer core 1910 can be coated with several conductive layers 1920, 1930 separated by insulating dielectric layers 1940. The assembly 1900 can be coated externally with a conductive layer 1950, such as a silver / silver chloride coating that forms a reference electrode. The polymer core 1910 can allow for flexibility and overall tissue compliance of the analyte sensor assembly 1900.

[0185] For example, the flexible polymer core 1910 can be coated with a conductive ink suitable for electrochemical sensing, such as a screen printed platinum ink. The conductor coated polymer core 1901 can then be coated with an insulating dielectric layer 1940, such as polyurethane. A second conductive layer 1930 can be coated on top of the insulating dielectric layer 1940, followed by another layer of insulating dielectric layer 1940. This process can be repeated to build up alternating layers of conductors and insulating dielectrics, and can end with a final conductive layer 1950.

[0186] The conductive layers 1920, 1930 can form electrodes, and the desired electrode contacts can be formed by selective ablation of material, such as with a laser. The conductive layers 1920, 1930 can be metal or other conductive material suitable for electrochemical sensing, such as graphitic carbon. The conductive layers 1920, 1930 can have the same or different compositions for each layer, for example, all Pt, Pt and C, Au and C, or combinations thereof. The conductive layer 1950 can be formed from Ag / AgCl. In an embodiment, the stack of the assembly 1900 can have a core 1910 with a diameter of about 50 μm, a conductive layer with a thickness of about 5 μm, an insulating layer with a thickness of about 25 μm, and a reference electrode with a thickness of about 25 μm, resulting in a sensor with a diameter of about 280 μm. In some embodiments, the core 1910 is formed from one or more polymers.

[0187] 20A and 20B illustrate a coaxial analyte sensor assembly 2000 including a wire core, according to an embodiment. The assembly 2000 can include a core 2010, which can be formed from a polymer or other material, a first conductive layer 2020, a second conductive layer 2030, an insulating layer 2040, and a reference electrode layer 2050. The assembly can extend between a first end 2002 and a second end 2004.

[0188] In the assembly 2000, the core 2010 can extend along the length of the assembly, and the wire core 2010 can be coated with an insulating dielectric layer 2011, such as polyurethane or other insulating material. The core 2010 can be made of an electrochemical sensing material. A first conductive layer 2020 can be coated on top of the insulating dielectric layer 2011, followed by another layer of insulating dielectric layer 2011. Such coatings can be alternated as desired to form alternating layers of insulating and conductive materials. The final electrode can be the outermost conductive layer 2050.

[0189] Similar to the assembly 1900 above, the sensing electrodes and electrode contacts can be formed by selective ablation as shown in FIG. 20B. The wire core 2010 and conductive layers 2020, 2030 can be metal or other conductive material suitable for electrochemical sensing, such as graphitic carbon. The wire core and conductive layers can have the same or different compositions for each layer, for example, all Pt, Pt and C, Au and C, or combinations thereof. The reference electrode can be formed from Ag / AgCl. In an embodiment, the core 2010 can be about 50 μm in diameter, the insulating layer 2040 can be about 25 μm thick, and the conductive layer can be about 5 μm thick. In the exemplary analyte sensor assemblies 1900 and 2000, a flexible combination of materials can be used when coating the core components.

[0190] 21A and 21B illustrate a double-sided stacked planar analyte sensor, according to an embodiment. The assembly 2100 can include a substrate 2110, a first electrode 2120, an insulating layer 2130, a second electrode 2140, and a third electrode 2150. Similar to the assembly 500 discussed above, the assembly 2100 can be stacked such that a sensing end of the assembly 2100 has a stepped cross-section.

[0191] In the sensor assembly 2100, a three-electrode sensor is shown having a working electrode (WE) 2120, a counter electrode (CE) 2131, and a reference electrode (RE) 2140. In the sensor assembly 2100, the electrodes are stacked or staggered and geometrically offset from one another along the z-axis. In the sensor assembly 2100, instead of the coplanar arrangement discussed above, multiple conductive and insulating layers are stacked. The conductive layers can be staggered for designated exposure of the electrodes 2120, 2131, and 2140. In the assembly 2100, the working electrode 2120 can be stacked on either side of the assembly 2100 to allow for two working electrodes.

[0192] Coplanar double-sided analyte sensor Discussed herein with reference to Figures 22A-28C are several examples of double-sided planar sensors having multiple electrodes located coplanar with respect to one another. These examples are also often connected through a planar substrate through one or more interconnects. Shown here is a distal portion of the sensor with various electrodes.

[0193] For example, a continuous analyte sensor can include a substrate having a first side and a second opposing side. One or more electrodes can be located on either side of the substrate. The electrodes can include, for example, working, reference, or counter electrodes in various quantities and configurations. When two or more electrodes are on a single side of the substrate, the electrodes are substantially coplanar with one another. Each of the electrodes generally has one or more electrical traces extending from the electrode. The electrical traces can extend to electrical connection pads or points. In some cases, these traces can travel from the first side of the substrate to the second side of the substrate along various interconnects.

[0194] 22A and 22B, for example, illustrate a double-sided coplanar analyte sensor 2200. The double-sided coplanar analyte sensor 2200 can have a first side 2200A and a second side 2200B opposite the first side 2200A. The double-sided coplanar analyte sensor 2200 can include a substrate 2205 having a proximal portion 2202 and a distal portion 2204. Located on the substrate 2205 on the first side 2200A can be a first reference electrode 2210 associated with a reference electrode trace 2212 and a first working electrode 2220 associated with a working electrode trace 2222. Located on the substrate 2205 on the second side 2200B may be a counter electrode 2230 associated with a counter electrode trace 2232, a second working electrode 2240 associated with a reference electrode trace 2242 and interconnect 2244, a second reference electrode 2250 associated with a working electrode trace 2252, and a third working electrode 2260 associated with a working electrode trace 2262 and interconnect 2264.

[0195] 22A depicts a first side 2200A of a double-sided coplanar analyte sensor 2200, in which a first working electrode 2220 and a first reference electrode 2210 are located coplanar with respect to one another on a substrate 2205. The first working electrode 2220 is distal to the first reference electrode 2210. In some embodiments, the arrangement of the first reference electrode 2210 and the first working electrode 2220 can be switched such that the first reference electrode 2210 is more distal.

[0196] 22B depicts a second side 2200B of the double-sided coplanar analyte sensor 2200, in which a counter electrode 2230, a second working electrode 2240, a second reference electrode 2250, and a third working electrode 2260 are disposed coplanar with one another on a substrate 2205. The third working electrode 2260 can be distal to the other electrodes.

[0197] As discussed above, in the presence of one or more analytes, an electrochemical reaction can cause a current to flow between the working electrode and any counter electrode, and the raw sensor signal can be based on the current. If present, a reference electrode can provide a stable reference potential and can conduct very little current. Any signals from the electrodes can be transmitted through traces and interconnects in the double-sided coplanar analyte sensor 2300.

[0198] The various electrodes can be flush with one another, as opposed to being stacked. By arranging the electrodes on a same plane, the overall thickness of the sensor is reduced compared to a stacked electrode design. A thinner sensor can improve user comfort during deployment and wear. Another advantage is that the flush electrode architecture facilitates ease of film deposition. The various electrodes can be aligned longitudinally along the substrate 2205. Various electrical traces 2212, 2222, 2232, 2242, 2252, and 2262 associated with each of the corresponding electrodes can provide electrical connections for the electrodes. For example, working electrode traces 2262 and 2242 can extend down the length of the substrate 2205 from the more distally located associated working electrodes (2260 and 2240, respectively) toward the proximal portion 2202 so that the working electrodes 2260 and 2240 can be electrically coupled to connector pads or points. To avoid these traces crossing other electrodes on this side of the substrate, the traces may extend through the substrate from the second side 2200B to the first side 2200A, if desired.

[0199] For example, starting with the third working electrode 2260, the associated working electrode trace 2262 can extend proximally from the third working electrode 2260 to the interconnect 2264. At the interconnect 2264, the associated working electrode trace 2262 can extend through the substrate from the second side 2200B to the first side 2200A. This can allow the associated working electrode trace 2262 to continue extending proximally along the length of the substrate toward a connector or connection pad without extending through other electrodes on the second side 2200B, such as the second reference electrode 2250, the second working electrode 2240, or the counter electrode 2230.

[0200] Similarly, starting from the second working electrode 2240, an associated working electrode trace 2242 can extend through the first side 2200A of the substrate 2205 from the second working electrode 2240 to the interconnect 2244. This can allow the trace to extend proximally from the second working electrode 2240 without interfering with the counter electrode 2230.

[0201] The use of such interconnects to route traces through and along both sides of the planar substrate 2205 can conserve space within the double-sided coplanar analyte sensor 2200 itself, allowing for thinner margins around the electrodes thereon.

[0202] 23A-23D illustrate a double-sided coplanar analyte sensor 2300, according to an embodiment. The double-sided coplanar analyte sensor 2300 can have a first side 2300A and a second side 2300B opposite each other. The double-sided coplanar analyte sensor 2300 can include a substrate 2305 having a proximal portion 2302 and a distal portion 2304.

[0203] FIG 23A depicts a top view of the first side 2300A. FIG 23B depicts a top view of the second side 2300B. FIG 23C depicts a side view of the double-sided coplanar analyte sensor 2300, showing that the electrodes thereon are coplanar with one another. FIG 23D depicts a view of the double-sided coplanar analyte sensor 2300 without the substrate 2305 to visualize the various electrodes, traces, and interconnects.

[0204] Located on the substrate 2305 on the first side 2300A can be a first reference electrode 2310, a second reference electrode 2320 associated with a reference electrode trace 2322 and an interconnect 2324, and a counter electrode 2330 associated with a counter electrode trace 2332. The first reference electrode 2310, the second reference electrode 2320, and the counter electrode 2330 can be coplanar with respect to one another.

[0205] The first reference electrode 2310 and the second reference electrode 2320 can be of similar or different sizes. The counter electrode 2330 can be of a regular or irregular shape. In an embodiment, the counter electrode 2330 can be distal to the reference electrodes 2320 and 2310.

[0206] Located on the substrate 2305 on the second side 2300B can be a first working electrode 2340 associated with a working electrode trace 2342, a second working electrode 2350 associated with a working electrode trace 2352 and interconnects 2354, 2356, and a third working electrode 2360 associated with a working electrode trace 2362 and interconnects 2364, 2366, where all three working electrodes 2340, 2350, and 2360 can be on the same side of the substrate 2305 and can all be coplanar with respect to one another. The working electrodes 2340, 2350, and 2360 can be approximately the same size and can be equally spaced from one another.

[0207] A trace 2352 associated with the second working electrode 2350 can extend proximally along the second side 2300B of the substrate 2305 to a first interconnect 2354, at which point the electrical connection can proceed through the substrate 2305 to the first side 2300A and the associated working electrode trace 2352 can continue to extend proximally along the substrate 2305. At the second interconnect 2356, the electrical connection can return through the substrate 2305 to the second side 2300B where the associated working electrode trace 2352 can continue to extend proximally to allow electrical connection to a connection pad of the second working electrode 2350. This can help to avoid the associated working electrode trace 2352 crossing other traces and electrodes on the substrate 2305.

[0208] Similarly, a working electrode trace 2362 associated with the third working electrode 2360 may extend through a first interconnect 2364 to the first side 2300A and then return through an interconnect 2366 to the second side 2300B.

[0209] 24A and 24B illustrate a double-sided coplanar analyte sensor 2400, according to an embodiment. The double-sided coplanar analyte sensor 2400 can have a first side 2400A and a second side 2400B opposite each other. The double-sided coplanar analyte sensor 2400 can include a substrate 2405 having a proximal portion 2402 and a distal portion 2404.

[0210] Figure 24A depicts a top view of the substrate 2405 on a first side 2400 A. Figure 24B depicts a top view of the substrate 2405 on a second side 2400 B.

[0211] Located on the substrate 2405 of the first side 2400A can be a first reference electrode 2410 associated with a reference electrode trace 2412, a second reference electrode 2420 associated with a reference electrode trace 2422 and an interconnect 2424, and a counter electrode 2430 associated with a counter electrode trace 2432. The counter electrode 2410, the first reference electrode 2420, and the second reference electrode 2430 can be coplanar with each other. The first reference electrode 2420 and the second reference electrode 2430 can be the same or different sizes. The counter electrode 2430 can be irregularly shaped and can be the most distal compared to the reference electrodes 2410 and 2420.

[0212] Located on the substrate 2405 on the second side 2400B can be a first working electrode 2440 associated with a working electrode trace 2442, a second working electrode 2450 associated with a working electrode trace 2452 and interconnects 2454, 2456, and a third working electrode 2460 associated with a working electrode trace 2462 and interconnect 2464.

[0213] As with the previous embodiment, the traces associated with the various electrodes can be routed between the two sides of the substrate through the use of interconnects, which can help avoid traces crossing over other co-planar electrodes on either side of the substrate.

[0214] 25A-25E illustrate a double-sided coplanar analyte sensor 2500, according to an embodiment. The double-sided coplanar analyte sensor 2500 can have a first side 2500A and a second side 2500B opposite each other. The double-sided coplanar analyte sensor 2500 can include a substrate 2505 having a proximal portion 2502 and a distal portion 2504.

[0215] FIG 25A depicts a top view of a first side 2500A of the substrate 2505, and FIG 25B depicts a top view of a second side 2500B of the substrate 2505. FIG 25C depicts a view of the double-sided coplanar analyte sensor 2500 without the substrate 2505 to see the various electrodes, traces, and interconnects. FIG 25D depicts a side view of the double-sided coplanar analyte sensor 2500 including the substrate 2505.

[0216] Located on the substrate 2505 on the first side 2500A may be a counter electrode 2510, a first reference electrode 2520 associated with a reference electrode trace 2522 and an interconnect 2524, and a second reference electrode 2530 associated with a reference electrode trace 2532.

[0217] The counter electrode 2510, the first reference electrode 2520, and the second reference electrode 2530 can be coplanar with one another. The first reference electrode 2520 and the second reference electrode 2530 can be the same or different sizes. The counter electrode 2510 can be relatively rectangular or can have tapered edges or alternative shapes as desired. Figure 25E depicts a version of a double-sided coplanar analyte sensor 2500 with a counter electrode 2510 having a different shape.

[0218] Located on the substrate 2505 on the second side 2500B can be a first working electrode 2540 associated with a working electrode trace 2542, a second working electrode 2550 associated with a working electrode trace 2552 and interconnects 2554, 2556, and a third working electrode 2560 associated with a working electrode trace 2562 and interconnect 2564.

[0219] As with the previous embodiment, the traces associated with the various electrodes can be routed between the two sides of the substrate through the use of interconnects, which can help avoid traces crossing over other co-planar electrodes on either side of the substrate.

[0220] 26A-26C illustrate a double-sided coplanar analyte sensor, according to an embodiment. The double-sided coplanar analyte sensor 2600 can have a first side 2600A and a second side 2600B opposite each other. The double-sided coplanar analyte sensor 2600 can include a substrate 2605 having a proximal portion 2602 and a distal portion 2604.

[0221] Figure 26A depicts a top view of the double-sided coplanar analyte sensor 2600 on a first side 2600A, and Figure 26B depicts a top view of the double-sided coplanar analyte sensor 2600 on a second side 2600B. Figure 26C depicts a side view of the double-sided coplanar analyte sensor 2600.

[0222] Located on the substrate 2605 on the first side 2600A may be a counter electrode 2610 associated with a counter electrode trace 2612, a first reference electrode 2620 associated with a reference electrode trace 2622 and interconnect 2624, and a second reference electrode 2630 associated with a reference electrode trace 2632 and interconnect 2634.

[0223] The counter electrode 2610, the first reference electrode 2620, and the second reference electrode 2630 can be coplanar with each other. The first reference electrode 2620 and the second reference electrode 2630 can be the same or different sizes.

[0224] Located on the substrate 2605 on the second side 2500B can be a first working electrode 2640 associated with a working electrode trace 2642 and interconnect 2644, a second working electrode 2650 associated with a working electrode trace 2652 and interconnects 2654, 2656, and a third working electrode 2660 associated with a working electrode trace 2662 and interconnect 2664. In the double-sided coplanar analyte sensor 2600, the working electrodes 2640, 2650, and 2660 can have equal but reduced spacing between them.

[0225] As with the previous embodiment, the traces associated with the various electrodes can be routed between the two sides of the substrate through the use of interconnects, which can help avoid traces crossing over other co-planar electrodes on either side of the substrate.

[0226] 27A-27D illustrate a double-sided coplanar analyte sensor 2700, according to an embodiment. The double-sided coplanar analyte sensor 2700 can have a first side 2700A and a second side 2700B opposite each other. The double-sided coplanar analyte sensor 2700 can include a substrate 2705 having a proximal portion 2702 and a distal portion 2704.

[0227] FIG 27A depicts a top view of the double-sided coplanar analyte sensor 2700 on a first side 2700A of the substrate 2705. FIG 27C depicts a top view of the double-sided coplanar analyte sensor 2700 on a second side 2700B of the substrate 2705. FIG 27B depicts a side view of the double-sided coplanar analyte sensor 2700. FIG 27D shows a view of the double-sided coplanar analyte sensor 2700 with the substrate 2705 to see the various electrodes, traces, and interconnects.

[0228] Located on the substrate 2705 on the first side 2700A can be a first reference electrode 2710 associated with a reference electrode trace 2712, and a second working electrode 2720 associated with a reference electrode trace 2722. The first reference electrode 2710 and the second reference electrode 2720 can be coplanar with one another. The first reference electrode 2710 and the second reference electrode 2720 can be similar or different sizes.

[0229] Located on the substrate 2705 on the second side 2700B can be a counter electrode 2730 associated with a counter electrode trace 2732, a first working electrode 2740 associated with a reference electrode trace 2742, a second reference electrode 2750 associated with a working electrode trace 2752 and an interconnect 2754, and a third working electrode 2760 associated with a working electrode trace 2762 and an interconnect 2764.

[0230] As with the previous embodiment, the traces associated with the various electrodes can be routed between the two sides of the substrate through the use of interconnects, which can help avoid traces crossing over other co-planar electrodes on either side of the substrate.

[0231] In a double-sided coplanar analyte sensor 2700, having the counter electrode 2730 on the second side 2700B of the substrate 2705 having the working electrodes 2740, 2750, 2760 can allow more room to increase the area of ​​one or more reference electrodes 2710, 2720.

[0232] 28A-C illustrate a double-sided coplanar analyte sensor 2800, according to an embodiment. The double-sided coplanar analyte sensor 2800 can have a first side 2800A and a second side 2800B opposite each other. The double-sided coplanar analyte sensor 2800 can include a substrate 2805 having a proximal portion 2802 and a distal portion 2804.

[0233] Figure 28A depicts a top view of the double-sided coplanar analyte sensor 2800 on a first side 2800A of a substrate 2805. Figure 28C depicts a top view of the double-sided coplanar analyte sensor 2800 on a second side 2800B of the substrate 2805. Figure 28B depicts a side view of the double-sided coplanar analyte sensor 2700.

[0234] Located on the substrate 2805 of the first side 2800A can be a first reference electrode 2810 associated with a reference electrode trace 2812, a second reference electrode 2820 associated with a reference electrode trace 2822 and an interconnect 2824, and a counter electrode 2830 associated with a counter electrode trace 2832, where the counter electrode 2830 can be distal to both the first reference electrode 2810 and the second reference electrode 2820.

[0235] Located on the substrate 2805 on the second side 2800B can be a first working electrode 2840 associated with a working electrode trace 2842, a second working electrode 2850 associated with a working electrode trace 2852 and interconnects 2854, 2856, and a third working electrode 2860 associated with a working electrode trace 2862 and interconnect 2864.

[0236] As with the previous embodiment, the traces associated with the various electrodes can be routed between the two sides of the substrate through the use of interconnects, which can help avoid traces crossing over other co-planar electrodes on either side of the substrate.

[0237] The various configurations of planar sensor electrode layouts depicted and discussed with reference to Figures 22A-28C all include flush two-sided configurations with interconnects through the substrate, which allow for efficient positioning of the various working, counter, and reference electrodes and their associated traces while maintaining a smaller overall space.

[0238] Sensor tip configuration A tip portion of an analyte sensor, such as the planar analyte sensors discussed herein, is often used during insertion of such a transcutaneous sensor. Often, an inflammatory response can occur following such insertion. Shown and discussed with reference to Figures 29-34 are examples of sensor tip designs for reducing inflammatory responses following insertion. For example, many of these designs allow for a reduced amount of tissue damage during insertion.

[0239] 29 illustrates a sensor 2900 having a tip portion 2906, according to an embodiment. The sensor 2900 can have a substrate 2905 extending between a distal portion 2902 and a proximal portion 2904. The sensor 2900 can include a tip portion 2906 having perforations 2908. The perforations 2908 can allow the tip portion 2906 to be more flexible or pliable during insertion, such as to reduce tissue damage and inflammatory response.

[0240] FIG. 30 illustrates a sensor 3000 having a tip portion 3006, according to an embodiment. The sensor 3000 can have a substrate 3005 extending between a distal portion 3002 and a proximal portion 3004. The sensor 3000 can include a tip portion 3006 made of a soft material. The tip portion 3006 can be made of a material having a softer quality than the material from which the remainder of the sensor 3000 is made. For example, the tip portion 3006 can be made of an elastomer, such as, for example, a hydrogel or silicone. In an embodiment, the tip portion 3006 can be made of a material having a durometer measurement less than the durometer measurement of the substrate 3005 material.

[0241] FIG. 31 illustrates a sensor 3100 having a tip portion 3106, according to an embodiment. The sensor 3100 can have a substrate 3105 extending between a distal portion 3102 and a proximal portion 3104. The sensor 3100 can include a tip portion 3106 having a cap secured to the distal portion 3102 of the substrate 3105. The tip portion 3106 can be, for example, rounded and can at least partially cover the distal end of the substrate 3105. The cap can be made of, for example, a hydrogel or an elastomer such as silicone. In an embodiment, the tip portion 3106 can be a cap formed by dipping the distal portion 3102 into such a material.

[0242] 32 illustrates a sensor 3200 having a tip portion 3206, according to an embodiment. The sensor 3200 can have a substrate 3205 extending between a distal portion 3202 and a proximal portion 3204. The sensor 3200 can include a tip portion 3206 that is bendable to provide damping to piercing forces during insertion. The tip portion 3206 can be bendable by the material it is made from or by the nature of its shape, such as by having a taper or recessed portion that allows the tip portion 3206 to be more flexible relative to the remainder of the substrate 3205.

[0243] 33 illustrates a sensor 3300 having a tip portion 3306, according to an embodiment. The sensor 3300 can have a substrate 3305 extending between a distal portion 3302 and a proximal portion 3304. The sensor 3300 can include the tip portion 3306, which is shown in an expanded view. In this embodiment, the tip portion 3306 can be a monolithic component with the substrate 3305. The tip portion 3306 can be perforated 3308, such as in a circular, oval, or square pattern. The perforations can be of a regular density along the tip portion 3306 to impart more flexibility thereto.

[0244] 34 illustrates a sensor 3400 having a tip portion 3406, according to an embodiment. The sensor 3400 can have a substrate 3405 extending between a distal portion 3402 and a proximal portion 3404. The sensor 3400 can include a tip portion 3406. In this embodiment, the tip portion 3406 can be a monolithic piece with the substrate 3405. The tip portion 3406 can include a rounded portion 3407 and two indentations 3408. The two indentations 3408 can allow the rounded portion 3407 to move back and forth during insertion, allowing for flexibility.

[0245] Combined amperometric and potentiometric sensor In some cases, more than one sensor type can be included on a planar sensor. In other words, multiple types of sensors can be integrated on the same planar substrate. For example, a planar substrate can accommodate a first sensor system and a second sensor system, both integrated on the planar substrate. In some cases, the first sensor system and the second sensor system can be located on the same side of the planar substrate. In some cases, the first sensor system and the second sensor system can be located on opposite sides of the planar substrate. In some cases, one or both of the first sensor system and the second sensor system can extend across the substrate and have components on both sides of the substrate.

[0246] One of the first sensor system or the second sensor system can be, for example, a continuous analyte sensor such as those discussed above with reference to Figures 22A-28 C. Such a sensor system can include, for example, a working electrode, a reference electrode, and at least one analyte sensing membrane.

[0247] The first sensor system can be a sensor system configured to make a first type of measurement, and the second sensor system can be a sensor system configured to make a second type of measurement that is different from the first type of measurement.

[0248] For example, one of the sensor systems can be an amperometric sensor, such as those discussed above. An amperometric sensor causes the oxidation or reduction of an electroactive species through the use of a potential applied between a reference electrode and a working electrode. The amperometric sensor can be used to measure the resulting current. Such an amperometric sensor can estimate interstitial glucose values ​​by measuring the current generated by the reaction of glucose with oxygen or an immobilized redox mediator. Examples of amperometric sensors can be found in U.S. Patent Application No. 63 / 403,568, entitled "CONTINUOUS MULTI-ANALYTE SENSOR DEVICES AND METHODS," filed September 2, 2022, which is incorporated herein by reference in its entirety.

[0249] In an embodiment, the other sensor can be a different type of electrochemical sensor, such as a potentiometric sensor or a conductivity sensor. For example, the other sensor system can be a potentiometric sensor. In such a sensor system, an electrode or membrane potential can then be measured. For example, a sensor measurement can be obtained based on the potential difference between two electrodes. In comparison, a conductivity sensor can be used to perform measurements of conductivity at a range of frequencies. An example of a potentiometric sensor can be found in U.S. Patent Application No. 63 / 403,582, entitled "DEVICES AND METHODS FOR MEASURING AN ELECTROPHYSIOLOGICAL SIGNAL AND / OR A CONCENTRATION OF A TARGET ANALYTE IN A BIOLOGICAL FLUID IN VIVO," filed on September 2, 2022, which is incorporated herein by reference in its entirety.

[0250] In an exemplary potentiometric sensor system, the sensor system can include a first electrode disposed on a substrate, an ionophore disposed on the substrate and configured to selectively transport target ions to or into the first electrode, and a second electrode disposed on the substrate. In this case, the potentiometric sensor system can further include sensor electronics. Such sensor electronics can be configured to generate a first signal corresponding to a current response, the current response based at least in part on a reaction at the working electrode corresponding to a concentration of a first analyte, and generate a second signal corresponding to an electromotive force, the electromotive force based at least in part on a potential difference generated between the first electrode and the second electrode in response to the ionophore transporting target ions corresponding to a concentration of a second analyte to the first electrode.

[0251] In some cases, the second sensor system can be a non-electrochemical sensor. For example, different types of sensors, such as an accelerometer or a blood oxygen level sensor, can be integrated all together on the substrate. In some cases, the first sensor system and the second sensor system can target different analytes in addition to different types of measurements.

[0252] In some cases, a third sensor system can be integrated into the planar substrate, in which case the third sensor system can be a different type of sensor or can be the same type of sensor as either the first or second sensor systems.

[0253] Sensors with L-shaped architecture 35A-36 depict an exemplary sensor architecture having an overall L-shape, where the substrate itself contains a bend or angle connecting the distal and proximal portions. The L-shaped architecture can be beneficial for insertion and detectability. In this way, the L-shaped architecture reduces or eliminates any bias forces that result from bending an otherwise straight sensor.

[0254] Figures 35A and 35B illustrate an L-shaped sensor 3500, according to an embodiment. Figure 35A depicts the L-shaped sensor 3500 in a first configuration 3500A, and Figure 35B depicts the L-shaped sensor 3500 in a second configuration 3500B.

[0255] The L-shaped sensor 3500 can include a planar substrate having a distal portion 3510 and a proximal portion 3520. The distal portion 3510 and the proximal portion 3520 can be joined together by a junction 3515. The junction 3515 can connect the distal portion 3510 and the proximal portion 3520 at a roughly perpendicular angle. The distal portion 3510 and the proximal portion 3520 can be approximately the same length or can be different lengths.

[0256] The distal portion 3510 can include electrodes 3512. A varying number of functional electrodes, such as working, reference, and counter electrodes, can be on the distal portion 3510. Exemplary electrode layouts are illustrated and discussed above with reference to Figures 22A-28C. One or more analyte sensing membranes can extend over the electrodes 3512 as desired.

[0257] The proximal portion 3520 can include a connection area that houses the connection pads 3532. The connection pads 3532 can be electrically connected to the electrodes 3512 that extend through traces through the interface portion 3515. The traces routed through the interface portion 3515 can do so without having to bend a flexible printed circuit. The proximal portion 3520 can have a greater width than the distal portion 3510.

[0258] The proximal portion 3520 of the first configuration 3500A is shown in a folded configuration. The proximal portion 3520 of the second configuration 3500B is shown in an unfolded configuration. Folding along the dotted lines in the second configuration 3500B can allow the host connection pads 3532 to be parallel to the transmitter printed circuit board assembly. In some cases, the folded portion 3530 can contain one or more interconnects.

[0259] 36 illustrates an L-shaped sensor 3600, according to an embodiment. The L-shaped sensor 3600 can include a distal portion 3610 and a proximal portion 3620 connected by a junction portion 3615.

[0260] The distal portion 3610 can include a first electrode 3612 and a second electrode 3614, which can be, for example, a working electrode, a reference electrode, a counter electrode, or combinations thereof. Additional electrodes can be on opposing sides of the substrate. The electrodes 3612, 3614 can be electrically connected through a trace 3618 that extends through the interface portion 3615.

[0261] The proximal portion 3620 can include connection pads 3625 electrically coupled to the electrodes 3612, 3614 (and any electrodes on the opposite side of the substrate) through traces 3618. In some cases, the L-shaped sensor 3600 can include a stiffener 3630 on the proximal portion 3620. The stiffener 3630 can provide mechanical and structural support to the L-shaped sensor 3600. Additionally, one or more functional components can be on the proximal portion 3620, such as supported by the stiffener 3630.

[0262] Sensor with cubic architecture 37A-39D depict exemplary sensor architectures that are cubic in nature. Such sensor architectures may be amenable to multi-analyte sensing and electrode miniaturization. Additionally, amperometric sensors may be limited by the space desired for a reference electrode. In the case of cubic sensors, there is additional room on various cubic surfaces for such a reference electrode.

[0263] 37A-37D depict a geometry for multi-analyte sensing where the reference and counter electrodes are on the sides of a cubic form factor. This can be done due to the small surface area available for each electrode in a planar geometry and the fact that the size of the reference and counter electrodes can be small and restrictive. In this concept, all or some of the sides of the cube can be coated with reference ink, and the two larger surfaces can be coated with electrode ink with an enzyme layer applied on top of it. This approach can maximize the reactive surface. Here, the electrodes can be placed next to each other in either one plane (front), two planes (front and back), or three to five planes (front and back and sides in a cubic design). The sensor can be a PCB-based material with traces and electrodes.

[0264] 37A-37D illustrate a cubic sensor 3700, according to an embodiment. FIGS. 37A and 37B depict a front view of the cubic sensor 3700. FIGS. 37C and 37D depict a back view of the cubic sensor 3700. The cubic sensor 3700 can include a substrate 3705, a first working electrode 3710, a second working electrode 3720, a reference electrode 3730, a third working electrode 3740, and a fourth working electrode 3750.

[0265] The substrate 3705 may be effectively cubic having six sides. Each of the working electrodes 3710, 3720, 3740, 3750 may be on one of the major faces of the substrate 3705. In comparison, the reference electrode 3730 may be located on one of the smaller sides of the cubic substrate 3705. Figure 38 illustrates such a cubic sensor 3800 operably connected to a circuit board 3850, according to an embodiment.

[0266] Each of the working electrodes 3710, 3720, 3740, 3750 can include a membrane thereon. Different types of enzyme layers can be used on each of the working electrodes as desired, such as to detect multiple types of analytes. In some cases, strings of cubic sensors can be used connected together.

[0267] 39A-39D depict a method of making a cubic sensor, according to an embodiment. As prepared, after application of such an enzyme layer on the working electrode, the cubic sensor 3700 can then be coated with a variable resistance layer, such as through deposition or dipping. Shown here is an exemplary process of dipping two enzyme layers and then a resistance layer. This process can utilize application of a masking sheet in a first step to first coat the upper working electrode (FIG. 39A), and then dipping length parameter control to dipping the second enzyme layer as well as the resistance layer (FIG. 39B).

[0268] In some cases, more layers of both can be added by changing the immersion parameters along the way (FIG. 39C). In some cases, alternative methods of producing the enzyme and resistance layers for the working electrode can be used. For example, they can be spray coated. To facilitate the addition of the enzyme and resistance layers, the sensor can be provided in an interconnected form factor, as depicted in the following figure.

[0269] Various approaches can be used to coat the reference ink on the side of the substrate and create the reference electrode. For example, the entire sensor is sprayed or deposited with the reference ink, while the larger surface can be covered with a masking layer of polymer, and then the masking layer is removed to add the membrane and resistive layer for the working electrode. The reference electrode can also be spray coated to be consumed on the sides and tip of the cube.

[0270] A pin can be connected to each extended electrode to apply electrical connections to the wearable and transmitter. After all the polymer films have been applied, the sensor is then cut into individual sensors using laser cutting or a similar method (FIG. 39D).

[0271] Methods for manufacturing multi-analyte sensors and membranes - Patents.com The sensors discussed herein can include membranes, such as those discussed above, made in a variety of ways. In some cases, the membrane can target glucose as an analyte. In some cases, the membrane can target two or more analytes, such as glucose and an additional analyte such as lactate. When a multi-analyte membrane is used, the membrane can contain more than one type of enzyme layer to aid in the detection of various analytes. In some cases, such membranes can extend across two or more working electrodes. In some cases, different membranes with different enzyme layers can be produced on different working electrodes, such that each working electrode targets a specific analyte.

[0272] 40 depicts a flow diagram illustrating a method of making a planar analyte sensor membrane, according to an embodiment. As discussed above, a variety of methods can be utilized to generate sensor substrates and electrodes. Similarly, a wide variety of methods can be utilized to generate membranes used for amperometric (or other electrochemical) sensing of analytes such as glucose or lactate.

[0273] For example, the membrane can be deposited on the electrode or formed simultaneously with the electrode. In some cases, jet valve dispensing can be used to produce such membranes. In some cases, slot die coating can be used to produce such membranes. In some cases, dipping can be used to produce such membranes. In some cases, individual dispensing can be used to produce such membranes. In some cases, an enzymatic layer (EZL) is deposited as a layer. In some cases, the membrane can include two or more EZLs, such as containing one or more analyte-sensitive enzymes. In some cases, such layers can detect multiple analytes, such as glucose, lactate, or other analytes. Such EZLs can often be layered on top of an intermediate layer (IL) that is deposited on the electrode region. After the IL and the first EZL, additional EZL layers can be deposited. Finally, a resistant layer (RL) can be deposited.

[0274] Method 4000 depicted in FIG. 40 depicts a slot-die membrane method of producing such a membrane, where the membrane is produced simultaneously on multiple sensor substrates, moving from left to right in the figure. First, in step 4010, aligned sensor substrates are received. Here, a first common IL is deposited by slot-die coating. This common IL is common to all electrodes to be membraned.

[0275] Next, in step 4020, an EZL layer is created on top of the common IL. Here, in the illustration of FIG. 40, a glucose-sensitive EZL is applied to the center electrode while different EZLs (e.g., targeted to different analytes) are deposited on the upper and lower electrodes. After this, in step 4030, a resistive layer is deposited on top of the EZL layer. Again, the middle electrode is coated with a RL targeted to glucose while the upper and lower electrodes are coated with RLs targeted to different analytes. In this way, multiple planar sensors can be prepared simultaneously with electrodes targeted to multiple analytes.

[0276] Digital Sensor In various examples described herein, an analyte sensor, such as any of the analyte sensors described herein, is electrically coupled to sensor electronics, such as sensor electronics 106. Electrochemical reactions at the electrodes of the analyte sensor, as described herein, cause the analyte sensor to generate an analog signal indicative of the analyte concentration at the respective electrodes. As described herein, the analog signal can be a current in the picoamp range. In some arrangements, the analog signal is provided from the analyte sensor to the sensor electronics via a connector, such as a connector comprising one or more copper or other metal contacts.

[0277] However, passing an analog signal through a connector can lead to certain challenges. For example, the analyte sensor and sensor electronics may reside on or near the skin of the host. In that environment, moisture as well as other contaminants may be present. Moisture, contaminants, and other environmental factors in the host may interfere with the analog signal transmitted across the connector. Also, in some analyte sensors, the analog signal generated by the analyte sensor may have a relatively low magnitude. This may make the analog signal generated by the analyte circuitry susceptible to noise, interference, and other signal degradation that may occur in the connector between the analyte sensor and the sensor electronics.

[0278] These concerns may add cost and / or complexity to the analyte sensor system. For example, it may be desirable to make the connector as robust as possible, including sealing the connector or even sealing the sensor assembly. For example, the connector may be positioned within a housing that has sufficient structural strength to avoid deformation and may include a gasket or other suitable sealing mechanism to prevent moisture from reaching the electrical contacts of the connector. In some examples, the connector may include contacts that are mechanically coupled to springs that tend to maintain an electrical coupling between the contacts. However, even these mitigation measures may not fully address signal degradation in the connector. Noise resulting from passing an analog signal through a connector may still degrade the performance of the analyte sensor system and / or lead to premature failure.

[0279] Various embodiments described herein address these and other challenges by utilizing an analyte sensor that includes a substrate having an analog front-end circuitry mechanically and electrically coupled to the substrate. The substrate may include one or more traces that are electrically coupled to one or more electrodes of the analyte sensor and also electrically coupled to the analog front-end circuitry. In some embodiments, the mechanical coupling of the analog front-end circuitry to the substrate shields the connections between the analog front-end circuitry and the one or more traces, thereby protecting them from moisture, contaminants, and other environmental conditions.

[0280] The analog front-end circuit may include various sub-circuits for conditioning the analog signal received from the analyte sensor. In some embodiments, the analog front-end circuit may include an analog-to-digital converter for converting the analog signal to a digital signal. The digital signal may be provided to the sensor electronics via a connector, such as a connector comprising one or more copper or other metal contacts. Because the connector is after the analog front-end circuit in the signal chain, the signal transmitted across the connector can be digital (generated by an analog-to-digital converter in the analog front-end circuit). This arrangement may alleviate noise concerns associated with the connector, since digital signals may not be as susceptible to noise and other signal degradation as analog signals.

[0281] In some examples, a calibration check is applied to the analyte sensor, for example, during manufacturing. The calibration check may be applied, at least in part, to detect any manufacturing defects in the analyte sensor. If a manufacturing defect detected for the analyte sensor renders the analyte sensor unsuitable for use, the defective sensor may be discarded. In various examples, mechanically coupling the analog front-end circuitry to the substrate of the analyte sensor may reduce the risk of the sensor being discarded during the calibration check. For example, some portion of the calibration check failure may be due to degradation of the analog sensor signal between the analyte sensor itself and one or more test probes. In an arrangement such as that described herein, where the analog front-end circuitry is mechanically and electrically coupled to the substrate of the analyte sensor, the calibration check may be performed using one or more digital signals generated by the analog front-end circuitry. Because digital signals may be less susceptible to degradation in the presence of moisture and / or other environmental factors, this may reduce the number of calibration check failures due to signal degradation and therefore the total number of analyte sensors that are discarded during manufacturing.

[0282] FIG. 41 illustrates an example of an analyte sensor system 4100 including an analyte sensor 4104 electrically coupled to the sensor electronics 4106 via a connector 4130. The analyte sensor 4104 may include an analog front-end circuit 4126. Thus, the raw sensor signal passed to the sensor electronics 4106 via the connector 4130 may be a digital signal rather than an analog signal. As described herein, this may reduce signal degradation across the connector 4130 due to moisture and / or other environmental conditions. In some examples, the connector 4130 includes one or more sensor-side contacts electrically coupled to the analog front-end circuit 4126 and one or more electronics-side contacts electrically coupled to the sensor electronics 4106. The one or more sensor-side contacts and the one or more electronics-side contacts may be in physical contact with each other to electrically couple the analog front-end circuit 4126 to the sensor electronics 4106.

[0283] The analyte sensor 4104 may include electrodes 4121, 4122, 4124 that generate one or more electrical signals as described herein. The electrodes 4121, 4122, 4124 may be arranged in any suitable manner. In some examples, the analyte sensor 4104 may be configured according to a three-electrode arrangement including a working electrode, a counter electrode, and a reference electrode. In other examples, the analyte sensor 4104 may be arranged according to a two-electrode configuration including a working electrode and a reference / counter electrode. It will also be appreciated that in some examples, the analyte sensor 4104 may include two or more working electrodes. As described herein, different working electrodes may be configured to generate electrical signals indicative of concentrations of different analytes.

[0284] The analyte sensor 4104 may include a sensor substrate 4120. The sensor substrate 4120 may be a planar substrate, for example, as described herein. Any suitable material may be used for the planar substrate. In some examples, the planar substrate may be constructed from a fiberglass reinforced epoxy resin that may meet a suitable standard, such as, for example, the FR4 standard promulgated by the National Electrical Manufacturers Association (NEMA). In some examples, all or a portion of the sensor substrate 4120 is a flexible substrate, for example, similar to the substrate 410 described herein. The electrodes 4121, 4122, 4124 may be bonded to the sensor substrate 4120, in some examples, for example, as described herein. The sensor substrate 4120 may also include conductive traces 4132 deposited thereon. The conductive traces 4132 may electrically couple the various electrodes 4121, 4122, 4124 to the analog front-end circuitry 4126.

[0285] The analog front-end circuitry 4126 may include various signal conditioning circuits, such as, for example, a gating circuit 4194 similar to the gating circuitry 294, a measurement circuit 4102 similar to the measurement circuitry 202, and the like. For example, the measurement circuitry 4102 may be and / or include a potentiostat similar to the measurement circuitry 202 described herein. The analog front-end circuitry 4126 may also include an analog-to-digital converter 4128. The analog-to-digital converter 4128 may receive an analog signal and convert the analog signal to a digital signal. The digital signal generated by the analog-to-digital converter 4128 may be provided to the sensor electronics 4106 via a connector 4130.

[0286] The sensor electronics 4106 may include various components similar to the components of the sensor electronics 106 described in FIG. 2, for example. For example, the sensor electronics 4106 may include a processor 4105 similar to the processor 204, a memory 4108 similar to the memory 208, instructions 4107 similar to the instructions 206, data storage 4110 which may be similar to the data storage 210, one or more sensors 4112 similar to the sensors 212, a battery 4114 similar to the battery 214, wireless communication circuitry 4118 similar to the wireless communication circuitry 218, etc. It will be understood that in some examples, the sensor electronics 4106 may include various other components not shown in FIG. 41 and / or omit some components shown in FIG. 41. In some examples, the sensor electronics 4106 may communicate with one or more peripheral devices, such as the peripheral device 250, and / or one or more medical devices, such as the medical device 270.

[0287] The analog front-end circuitry 4126 may be arranged and packaged in any suitable manner. In some embodiments, the analog front-end circuitry 4126 may comprise an analog front-end chip including a substrate on which various components are positioned. For example, the substrate may be or include a silicon wafer with some or all of the components of the analog front-end circuitry 4126 fabricated on the silicon wafer. The silicon wafer may be packaged in any suitable enclosure. Also, in some embodiments, the analog front-end circuitry 4126 may comprise an FR4 or similar substrate on which various components of the analog front-end circuitry 4126 are connected. In some embodiments, the analog front-end circuitry 4126 may be or include a commercially available analog front-end circuit chip.

[0288] The various inputs and outputs of the analog front-end circuitry 4126 may comprise conductive contacts arranged as pins, pads, and / or the like. The analog front-end circuitry 4126 may be mechanically and electrically coupled to the sensor substrate 4120 in any suitable manner. For example, the analog front-end circuitry 4126 may be surface mounted to the sensor substrate 4120. Surface mounting may include making electrical connections between contacts of the analog front-end circuitry 4126 and corresponding contacts formed on the sensor substrate 4120. The electrical connections may be made using any suitable technique including, for example, aluminum wedge bonding, wire bonding, underfill, etc. In some embodiments, the technique for creating the electrical connections may mechanically couple the analog front-end circuitry 4126 to the sensor substrate 4120. Also, in some embodiments, the analog front-end circuitry 4126 may be mechanically coupled to the sensor substrate 4120 using mechanisms in addition to or in lieu of the mechanical coupling provided by the electrical connections. For example, an adhesive such as a non-conductive epoxy may be used to mechanically couple the analog front-end circuitry 4126 to the sensor substrate 4120.

[0289] FIG. 42 is a diagram illustrating one exemplary arrangement of an analog front-end circuit 4126. In the embodiment of FIG. 42, the analog front-end circuit 4126 includes an analog front-end chip 4202 and additional components 4208. The analog front-end chip 4202 includes various inputs and outputs. For example, the inputs and outputs of the analog front-end chip 4202 are implemented as pins, surface mount pads, and / or any other suitable connector arrangement. Exemplary inputs to the analog front-end chip 4202 include an input voltage (VDD), a regulator input (REG), and ground (GND).

[0290] In the embodiment of FIG. 42, the analog front-end chip 4202 comprises various inputs and outputs for interfacing with the sensor electronics 4106. In some embodiments, the inputs and outputs for interfacing with the sensor electronics 4106 are digital inputs and outputs. These may include, for example, a clock input (CLK), an interrupt line (INTB1), and various data inputs / outputs (e.g., D1, D2, ..., DN). The clock input may receive a clock signal generated by the sensor electronics 4106 (e.g., by and / or for the processor 4105). The interrupt lines may be used by the analog front-end chip 4202 to trigger one or more interrupts in one or more processors of the sensor electronics 4106, such as the processor 4105. The data inputs / outputs may be arranged to provide data to and / or receive data from the sensor electronics 4106. In some embodiments, the data inputs / outputs may be arranged for bidirectional data transfer and may include, for example, a MOSI input / output and a MISO input / output. In some embodiments, data transmitted from the analog front-end chip 4202 to the sensor electronics 4106 may be provided at a MISO input / output, and data transmitted from the sensor electronics 4106 to the analog front-end chip 4202 may be transmitted via a MOSI input / output.

[0291] The inputs and outputs of the analog front-end chip 4202, which communicate with the sensor electronics 4106, may be electrically coupled to the connector 4130 and may pass to and / or from the sensor electronics 4106 via the connector 4130. As described herein, the raw sensor signal provided by the analog front-end circuitry 4126 to the sensor electronics 4106 via the connector 4130 may be a digital signal, thus mitigating signal degradation at the connector 4130.

[0292] FIG. 42 also shows inputs and outputs of the analog front-end chip 4202 for interfacing with the electrodes 4121, 4122, 4124. The inputs and outputs for interfacing with the electrodes 4121, 4122, 4124 may be analog inputs and outputs. That is, for example, the signals passed at the inputs and outputs for interfacing with the electrodes 4121, 4122, 4124 may be analog signals. In the embodiment of FIG. 42, these include a reference electrode input / output (RE), a counter electrode input / output (CE), a first working electrode input / output (WE1), and a second working electrode input / output (WE2). It will be understood that the inputs and outputs of the analog front-end circuit 4126 for interfacing with the electrodes 4121, 4122, 4124 may vary depending on, for example, the electrodes included in the analyte sensor 4104. Also, in various embodiments, the analog front-end chip 4202 may receive inputs from various electrodes via the described inputs / outputs. For example, as described herein, the current provided by the working electrode may be indicative of the analyte concentration in the analyte sensor 4104. In some examples, the analog front-end circuitry 4126 may also provide a bias signal to one or more of the electrodes.

[0293] FIG. 42 also shows analog front-end components 4208 that are external to the analog front-end chip 4202. These include, for example, a capacitor C1 electrically coupled between ground and a regulator pin of the analog front-end chip 4202. Capacitors C2 and C3 are also electrically coupled between the input voltage VDD of the analog front-end chip 4202 and the input voltage pin VDD as shown. The capacitors C1, C2, C3 may provide power conditioning to the voltage and ground lines of the analog front-end chip 4202. It will be appreciated that in various embodiments there may be various different configurations of power conditioning capacitors and / or other components external to an analog front-end chip such as the analog front-end chip 4202. In some embodiments, the power conditioning capacitors may be fabricated on the sensor substrate 4120 using printing or any other suitable technique. Connections between the various capacitors and corresponding inputs / outputs of the analog front-end chip 4202 and the input voltage VDD may be provided by traces fabricated on the sensor substrate 4120 as described herein.

[0294] FIG. 43 illustrates one exemplary arrangement of an analyte sensor system 4300 including an analog front-end circuit 4326. In the embodiment of FIG. 43, the analyte sensor system 4300 includes a coaxially arranged electrode subassembly 4306. For example, the electrodes of the electrode subassembly 4306 can be in any suitable arrangement, such as those described herein, including with respect to, for example, FIGS. 3B, 3C, 15A-15D, 16A-16D, 17A-17D, 18, 19A, 19B, 20A, and 20B. The electrodes of the electrode subassembly 4306 can be electrically coupled to connectors 4302 and 4304 of the sensor substrate 4320. The connectors 4302 and 4304 can be any suitable connectors, including, for example, stamped metal type connectors. Traces (not shown in FIG. 43) may electrically couple the electrodes of the electrode subassembly 4306 to the analog front-end circuitry 4326, as described herein.

[0295] 44 illustrates another exemplary arrangement of an analyte sensor system 4300. The example of FIG. 44 includes a connector portion 4308. In this example, the connector portion 4308 may represent a portion of a zero insertion force (ZIF) connector. The connector portion 4308 may be coupled to a connector, such as the connector 4130, to couple the analog front-end circuitry 4326 to the sensor electronics 4106. For example, the sensor substrate 4320 may include traces electrically coupled to inputs / outputs of the analog front-end circuitry 4326 that interface with the sensor electronics 4106.

[0296] 45 illustrates another example arrangement of an analyte sensor system 4500 including an analog front-end circuit 4526. In the example of FIG. 45, the analyte sensor system 4500 includes an electrode subassembly 4506 having electrodes fabricated on a sensor substrate 4520. For example, the electrodes of the electrode subassembly 4506 may be arranged in any suitable manner, including, for example, those described herein with respect to Figures 4A-4G, 5A-5K, 6A-6E, 7A-7I, 8A-8F, 9, 10A and 10B, 11A-11C, 12, 13, 14A-14D, 21A, 21B, 22A and 22B, 23A-23D, 24A and 24B, 25A-25E, 26A-26C, 27A-27D, 28A-28C, 29-34, 35A and 35B, 36, 37A-37D, and 38-40. Traces (not shown in FIG. 45) may electrically couple the electrodes of the electrode subassembly 4506 to the analog front-end circuitry 4526, as described herein.

[0297] In the example of FIG. 45, the analog front-end circuitry 4526 may be positioned within a housing 4510. The housing 4510 is mechanically coupled to the analog front-end circuitry 4526 and / or the sensor substrate 4520. Any suitable mechanical coupling may be used. In some examples, the housing 4510 is snap-fitted onto the sensor substrate 4420. Also, in some examples, the housing 4510 is bonded to the sensor substrate 4520 using a bonding agent such as a suitable epoxy. Also, in some examples, the housing 4510 may be molded onto the sensor substrate. FIG. 46 illustrates an example of an analyte sensor system 4500 that includes a housing 4510′ molded onto the sensor substrate 4520. In various examples, as described herein, the housing 4510, 4510′ may shield the analog connections between the various electrodes and the analog front-end circuitry 4426 from moisture and other environmental conditions that may lead to signal degradation.

[0298] FIG. 47 illustrates another embodiment of an analyte sensor system 4500. In the embodiment of FIG. 47, the analog front-end circuitry 4526 is shown detached from the sensor board 4520. The sensor board 4520 includes a connector portion 4508 for interfacing with a connector 4130 to the sensor electronics 4106 as described herein. The sensor board 4520 also includes pads 4512. The pads 4512 are arranged to interface with inputs / outputs of the analog front-end circuitry 4526. For example, the analog front-end circuitry 4526 can be electrically coupled to the respective electrodes of the electrode subcommands and the focus becomes non-operator for the assembly 4506 via the pads 4512. Also, for example, some of the pads can be electrically coupled to traces extending from the respective electrodes. In some embodiments, the analog front-end circuitry 4526 can also be electrically coupled to the connector portion 4508 via the pads 4512. For example, the sensor substrate 4520 may include one or more traces connecting one or more of the pads 4512 to respective pads of the connector portion 4508.

[0299] In an arrangement including an analog front-end circuit coupled to a sensor substrate as described herein, the sensor substrate including the analog front-end circuit may be electrically coupled to the sensor electronics in any suitable manner. For example, a connector between the analyte sensor and the sensor electronics (e.g., connector 4130) may be implemented with a connector portion electrically coupled to the analyte sensor and a connector portion electrically coupled to the sensor electronics. For example, FIGS. 44 and 47 show an arrangement in which a ZIF connector is used to electrically couple the analyte sensor (e.g., sensor substrate) to the sensor electronics. The connector portions 4308 and 4508 of the analyte sensor may be configured to be electrically and mechanically coupled to corresponding connector portions in the sensor electronics.

[0300] In arrangements such as that described with respect to FIG. 2 where the analog front-end circuitry is part of the sensor electronics 106, and in arrangements similar to that shown in FIG. 41 where the analog front-end circuitry 4126 is positioned on the analyte sensor 4104, passing a signal from the analyte sensor 104, 4104 to the sensor electronics 106, 4106 can be a challenge. For example, the connection between the analyte sensor 104, 4104 and the sensor electronics 106, 4106 can be sensitive to leakage, moisture, and other factors that affect noise. When the connection between the sensor electronics 106, 4106 and the analyte sensor 104, 4104 includes physical contact, it may be desirable for such a connection (e.g., connector 4130) to be airtight. Contact-based hermetic connectors can be bulky and expensive to produce. This challenge may be addressed by placing an analog front-end circuit 4126 on the analyte sensor for 104, as described herein, which may result in a digital signal being passed across the connector 4130 instead of an analog signal. However, in some examples, the performance of the analyte sensor system may be further improved by utilizing a contactless connection. For example, the analyte sensor 4104 may be operably coupled (e.g., electrically coupled) to the sensor electronics 4106 utilizing a contactless connection (e.g., a wireless connection).

[0301] Figure 48 illustrates an embodiment of an analyte sensor system 4800 that includes an analyte sensor 4104 electrically coupled to sensor electronics 4106 via a contactless connector 4802. In the embodiment of Figure 48, the analyte sensor 4104 and the sensor electronics 4106 are arranged in a manner similar to that shown in Figure 41. For example, as shown in Figure 41 and Figure 48, the analog front-end circuitry 4126 is positioned on the sensor substrate 4120.

[0302] The contactless connector 4802 may be any suitable type of contactless connector. For example, the contactless connector 4802 may comprise a sensor side element 4804 and an electronics side element 4806. The sensor side element 4804 may be electrically coupled to the sensor 4104, such as via the analog front-end circuitry 4126. The electronics side element 4806 may be electrically coupled to the sensor electronics 4106. The sensor side element 4804 and the electronics side element 4806 may be positioned substantially proximate to each other to facilitate wireless communication between the sensor side element 4804 and the electronics side element 4806. In some examples, the sensor side element 4804 and the electronics side element 4806 may comprise one or more coils, antennas, or other similar elements that may be positioned within the sensor system 4800 such that the sensor side element 4804 and the electronics side element 4806 are in close proximity to each other and inductively coupled to each other without physical contact. It is contemplated that other antenna designs may be implemented to effect communication between the sensor system 4800 and the sensor side element 4804.

[0303] Positioning the sensor side element 4804 and the electronics side element 4806 substantially proximate to one another may include bringing the sensor side element 4804 and the electronics side element 4806 proximate to one another and aligning the two elements 4804, 4806. For example, the sensor side element 4804 and the electronics side element 4806 may be positioned to generate a wireless connection when the elements 4804, 4806 substantially overlap one another and are placed sufficiently proximate to one another such that power and / or data signals may be wirelessly transmitted from one element 4804, 4806 and received by the other element 4804, 4806. When the sensor side element 4804 and the transmitter side element 4806 are aligned, power and / or data may be transmitted across the contactless connector 4802.

[0304] The contactless connector 4802 may facilitate the transmission of data signals (e.g., unidirectional or bidirectional) and power between the analog front-end circuitry 4126 and the sensor electronics 4106. The data signals may include processed or unprocessed data. In one embodiment, the digital output of the analog front-end circuitry 4126 is, for example, as generated by the analog-to-digital converter 4128. The data signals may also include, for example, clock signals, interrupt signals, and / or the like. Power may be transmitted, for example, from the battery 4114 via the contactless connector 4802. In some embodiments, the power requirements of the analyte sensor 4104 may be relatively small. In some cases, the distance between the sensor-side element 4804 and the electronics-side element 4806 of the contactless connector 4802 may be small, such as less than 10 mm, more preferably less than 5 mm, and even more preferably less than 1 mm. Power may be provided continuously, or in some cases may be provided on an as-needed basis. It is contemplated that in some embodiments, the contactless connector 4802 may be configured to operate for short-range communications, such as Radio Frequency ID (RFID) communications or near-field communications. In such embodiments, a suitable operating frequency (e.g., 13.56 MHz, 433 MHz, 860-960 MHz) may be selected for such operation. In the embodiment of FIG. 48, the analog front-end circuitry 4126 is positioned at the analyte sensor 4104, and the signal across the contactless connector 4802 is digital. It will be understood that in various embodiments, a contactless connector such as the contactless connector 4802 may be used in an arrangement in which the components of the analog front-end circuitry 4126 are positioned at the sensor electronics 4106, and the signal across the contactless connector 4802 is analog (in whole or in part), similar to the arrangement shown in FIG. 2.

[0305] FIG. 49 illustrates one arrangement of an analyte sensor system 5000 that includes a sensor substrate 5020 with a coil 5004 positioned thereon. The coil 5004, in some embodiments, includes a trace positioned on the sensor substrate 5020 in the shape of a coil or other suitable shape for inductively coupling to an electronics component. In the embodiment of FIG. 50, an analog front-end circuit 5026 is also positioned on the sensor substrate 5020, as described herein. In the arrangement of FIG. 49, an analog sensor 5006 is positioned on the sensor substrate 5020. In this embodiment, the analyte sensor 5006 is separated from the remainder of the sensor substrate 5020 via a cut 5008. The analyte sensor 5006 may be configured to bend down the remainder of the sensor substrate 5020 to facilitate insertion into a host, as described herein.

[0306] FIG. 50 illustrates another arrangement of an analyte sensor system 5000 including a sensor electronics 5010. As shown, the sensor electronics 5010 includes an electronics side coil 5022 positioned to be inductively coupled to a sensor side coil 5004. In the embodiment of FIG. 50, the sensor electronics 5010 includes a battery 5024 and other components 5012, which may include, for example, any of the sensor electronics components described herein. An analog front-end circuit 5026 is also shown. Additionally, FIG. 50 illustrates an analyte sensor 5006 bent distally relative to the remainder of the sensor substrate 5020 inserted into the host tissue 5030.

[0307] In various embodiments, the contactless connector arrangements shown in FIGS. 48-50 may eliminate the need for air tightness between the sensor electronics and the analyte sensor, thereby improving noise performance and reducing size and potentially cost. In some embodiments, contactless connector arrangements such as those shown in FIGS. 48-50 may be implemented with a reusable transmitter. In a reusable transmitter arrangement, all or part of the sensor electronics are positioned within an enclosure or housing, such as the electronics unit 318 shown in FIG. 3A. The transmitter enclosure or housing may be reused with multiple embodiments of the analyte sensor. For example, once a sensor session with one analyte sensor is completed, the transmitter enclosure or housing (including the sensor electronics) may be removed from the analyte sensor and then mechanically and electrically coupled to a new analyte sensor for a new sensor session. The old sensor is disposable, in some embodiments.

[0308] In some examples, the analyte sensor for 104 and the sensor electronics 4106 may be configured to begin operation upon creation of the contactless connector 4802. For example, the sensor electronics 4106 may begin transmitting power to the analyte sensor for 104 once the sensor side element 4804 and the electronics side element 4806 are positioned to create the contactless connector 4802. Similarly, the analyte sensor 4104 may begin transmitting a sensor signal to the sensor electronics 4106 once the contactless connector 4802 is created. In some examples, creation of the contactless connector 4802 occurs when the reusable transmitter housing is mechanically coupled to the analyte sensor 104, thus positioning the sensor side element 4804 and the electronics side element 4806 to create the contactless connector 4802.

[0309] 48-50, the use of non-contact connectors in an arrangement having a reusable transmitter and a disposable analyte sensor can, in some embodiments, result in a simpler and less expensive design for both components. For example, instead of separate electrical and mechanical coupling mechanisms, such an arrangement can use a mechanical coupling arrangement that also aligns the sensor side element 4804 and the electronics side element 4806.

[0310] In some examples, the sensor electronics can be fabricated on a sensor electronics board. The sensor electronics board can include a side load connector portion. The side load connector portion can receive an analyte sensor connector portion, such as, for example, one of the connector portions 4308, 4508 described herein.

[0311] In some examples, the connector portion on the analyte sensor may include a plurality of pins and the connector portion on the sensor electronics may include a plurality of receptacles. The analyte sensor may be positioned such that the pins are mechanically received within the receptacles to create an electrical and mechanical coupling between the analyte sensor and the sensor electronics. In some arrangements, the pins may include sharp ends. The receptacles may include a conductive elastomer. The connector portion from the analyte sensor may be coupled to the connector portion from the sensor electronics by forcing the sharp ends of the pins into the conductive elastomer.

[0312] In some examples, the connector portion of the analyte sensor and / or the connector portion of the sensor electronics comprises a flexible cable. The flexible cable may be made from wire and / or may be printed onto a flexible substrate. When the two connector portions are joined, the flexible cable may facilitate positioning of the analyte sensor relative to the sensor electronics.

[0313] In some examples, the connector portion of the analyte sensor may include one or more conductive tabs. The connector portion of the sensor electronics may have a corresponding conductive tab. Each conductive tab may be arranged to be mechanically resilient. The analyte sensor and / or the sensor electronics may additionally include a snap mechanism. When a conductive tab of the analyte sensor is brought into contact with a conductive tab of the sensor electronics, each tab may provide resistance until the snap mechanism engages to hold the analyte sensor and the sensor electronics in a mechanically coupled position. An electrical coupling between the analyte sensor and the sensor electronics may be provided by contact between the conductive tabs.

[0314] In some examples, the connector portion of the analyte sensor and / or the connector portion of the sensor electronics include a gasket or other similar sealing mechanism that can be engaged when the two connector portions are brought into contact to protect the connection from moisture and / or other environmental factors.

[0315] In some examples, the connector portion of the analyte sensor and / or the connector portion sensor electronics can include a conductive adhesive film that can mechanically and electrically couple the connector portions when the two connector portions are brought into mechanical contact with each other.

[0316] Various notes and examples Example 1 is a continuous analyte sensor comprising: a substrate having a first side and a second side opposite the first side, the substrate being planar; a first working electrode on the substrate; a second working electrode on the substrate; a reference electrode on the substrate, wherein the first working electrode, the second working electrode, and the reference electrode are each planar electrodes, at least two of the first working electrode, the second working electrode, or the reference electrode are on the first side of the substrate and any remaining planar electrodes are on the second side of the substrate, and at least two of the first working electrode, the second working electrode, and the reference electrode are coplanar with one another; and an interconnect extending through the substrate between the first side and the second side, the interconnect in electrical communication with one of the reference electrode, the first working electrode, or the second working electrode.

[0317] In Example 2, the subject matter of Example 1 optionally includes, wherein the first working electrode and the second working electrode are on a first side of the substrate and the reference electrode is on a second side of the substrate.

[0318] In Example 3, the subject matter of Example 2 optionally includes, wherein the first working electrode and the second working electrode are coplanar with one another.

[0319] In Example 4, the subject matter of any one or more of Examples 1-3 optionally includes wherein the first working electrode and the reference electrode are on a first side of the substrate and the second reference electrode is on a second side of the substrate.

[0320] In Example 5, the subject matter of Example 4 optionally includes, wherein the first working electrode and the reference electrode are coplanar with one another.

[0321] In Example 6, the subject matter of any one or more of Examples 1-5 optionally includes, where the first working electrode is spaced distally from the second working electrode on the substrate.

[0322] In Example 7, the subject matter of any one or more of Examples 1-6 optionally includes, wherein the first working electrode and the second working electrode each have a substantially equal surface area.

[0323] In Example 8, the subject matter of any one or more of Examples 1-7 optionally includes, where the reference electrode has a smaller surface area relative to a surface area of ​​either the first working electrode or the second working electrode.

[0324] In Example 9, the subject matter of any one or more of Examples 1-8 optionally includes a second reference electrode.

[0325] In Example 10, the subject matter of Example 9 optionally includes where the first working electrode and the second working electrode are on a first side of the substrate and the first reference electrode and the second reference electrode are on a second side of the substrate.

[0326] In Example 11, the subject matter of any one or more of Examples 1-10 optionally includes, wherein the first reference electrode has a smaller surface area relative to a surface area of ​​the second reference electrode.

[0327] In Example 12, the subject matter of any one or more of Examples 1-11 optionally includes a third working electrode, wherein the third working electrode is coplanar with at least one of the first working electrode, the second working electrode, or the reference electrode.

[0328] In Example 13, the subject matter of Example 12 optionally includes, wherein the first working electrode, the second working electrode, and the third working electrode are on a first side of the substrate.

[0329] In Example 14, the subject matter of Example 13 optionally includes, the first working electrode being spaced a first distance from the second working electrode on the substrate, and the second working electrode being spaced a second distance from the third working electrode on the substrate.

[0330] In Example 15, the subject matter of Example 14 optionally includes, the first distance and the second distance being approximately equal.

[0331] In Example 16, the subject matter of any one or more of Examples 12-15 optionally includes, wherein the first working electrode and the second working electrode are on a first side of the substrate and the third working electrode is on a second side of the substrate.

[0332] In Example 17, the subject matter of any one or more of Examples 12-16 optionally includes, wherein the first working electrode, the second working electrode, and the third working electrode each have a substantially equal surface area.

[0333] In Example 18, the subject matter of any one or more of Examples 1-17 optionally includes a first counter electrode, wherein the first counter electrode is a planar electrode.

[0334] In Example 19, the subject matter of Example 18 optionally includes, wherein the first counter electrode is coplanar with at least one of the first working electrode, the second working electrode, or the reference electrode.

[0335] In Example 20, the subject matter of any one or more of Examples 18-19 optionally includes where the first working electrode and the second working electrode are on a first side of the substrate and the reference electrode and the counter electrode are on a second side of the substrate.

[0336] In Example 21, the subject matter of Example 20 optionally includes a counter electrode spaced distally from a reference electrode on the substrate.

[0337] In Example 22, the subject matter of any one or more of Examples 18-21 optionally includes, where the counter electrode has a larger surface area than the reference electrode.

[0338] In Example 23, the subject matter of any one or more of Examples 18-22 optionally includes a second counter electrode, wherein the first counter electrode and the second counter electrode are each planar electrodes.

[0339] In Example 24, the subject matter of any one or more of Examples 1-23 optionally includes, wherein the first working electrode, the second working electrode, and the reference electrode are aligned longitudinally along the substrate.

[0340] In Example 25, the subject matter of any one or more of Examples 1-24 optionally includes at least one analyte sensing membrane extending over one or more of the first working electrode and the second working electrode.

[0341] In Example 26, the subject matter of Example 25 optionally includes providing at least one analyte sensing membrane comprising an enzyme layer configured to sense glucose.

[0342] In Example 27, the subject matter of any one or more of Examples 25-26 optionally includes, where the at least one analyte sensing membrane comprises an enzyme layer configured to sense lactate.

[0343] In Example 28, the subject matter of any one or more of Examples 25-27 optionally includes, at least one analyte sensing membrane configured to sense two or more analytes.

[0344] In Example 29, the subject matter of any one or more of Examples 1-28 optionally includes, wherein each of the first working electrode, the second working electrode, and the reference electrode has a boundary on the substrate.

[0345] In Example 30, the subject matter of any one or more of Examples 1-29 optionally includes, wherein the substrate comprises a tip portion extending distally from the first working electrode, the second working electrode, and the reference electrode.

[0346] In Example 31, the subject matter of Example 30 optionally includes, wherein the substrate further comprises a tip portion of the substrate that does not include the first working electrode, the second working electrode, and the reference electrode.

[0347] In Example 32, the subject matter of any one or more of Examples 30-31 optionally includes a tip portion that is perforated.

[0348] In Example 33, the subject matter of any one or more of Examples 30-32 optionally includes a tip portion that is rounded.

[0349] In example 34, the subject matter of any one or more of examples 30-33 optionally includes where the tip portion comprises a soft material.

[0350] In Example 35, the subject matter of any one or more of Examples 30-34 optionally includes, wherein the tip portion comprises a cap secured to the substrate at a distal end.

[0351] In Example 36, the subject matter of any one or more of Examples 30-35 optionally includes a tip portion that is bendable.

[0352] In Example 37, the subject matter of Example 36 optionally includes the tip portion comprising a depression and a rounded portion, the rounded portion being spaced distally from the depression.

[0353] Example 38 is a sensor comprising: a substrate having a first side and a second side opposite the first side, the substrate being planar; a first sensor system on the substrate, the first sensor system being a continuous analyte sensor configured to collect a first type of measurement, the first sensor system comprising a working electrode, a reference electrode on the substrate, the working electrode and the reference electrode each being a planar electrode, and at least one analyte sensing membrane extending over the at least one working electrode; and a second sensor system on the substrate, the second sensor system being configured to collect a second type of measurement different from the first type of measurement.

[0354] In Example 39, the subject matter of Example 38 optionally includes where the first sensor system comprises an amperometric sensor.

[0355] In Example 40, the subject matter of Example 39 optionally includes, the second sensor system comprising a potentiometric sensor.

[0356] In Example 41, the subject matter of Example 40 optionally includes the second sensor system comprising a first electrode disposed on a substrate, an ionophore disposed on the substrate and configured to selectively transport target ions to or within the first electrode, and a second electrode disposed on the substrate.

[0357] In Example 42, the subject matter of Example 41 optionally includes sensor electronics configured to generate a first signal corresponding to a current response, where the current response is based at least in part on a reaction at the working electrode corresponding to a concentration of a first analyte, and to generate a second signal corresponding to an electromotive force, where the electromotive force is based at least in part on a potential difference generated between the first electrode and the second electrode in response to the ionophore transporting a target ion corresponding to the concentration of a second analyte to the first electrode.

[0358] In Example 43, the subject matter of any one or more of Examples 41-42 optionally includes a first electrode of the second sensor system being on a first side of the substrate and a second electrode of the second sensor system being on a second side of the substrate.

[0359] In Example 44, the subject matter of any one or more of Examples 41 to 43 optionally includes where the first sensor system is on a first side of the substrate and the second sensor system is on a second side of the substrate.

[0360] In Example 45, the subject matter of any one or more of Examples 41-44 optionally includes, wherein the first sensor system and the second sensor system are both on a first side of the substrate.

[0361] In Example 46, the subject matter of any one or more of Examples 38-45 optionally includes a third sensor system.

[0362] In Example 47, the subject matter of Example 46 optionally includes the third sensor system being configured to collect a third type of measurement different from the first and second types of measurements.

[0363] In Example 48, the subject matter of any one or more of Examples 46-47 optionally includes, where the first sensor system and the third sensor system are amperometric sensors.

[0364] In Example 49, the subject matter of any one or more of Examples 46-48 optionally includes, where the second sensor system and the third sensor system are potentiometric sensors.

[0365] In Example 50, the subject matter of any one or more of Examples 38-49 optionally includes, where the first sensor system comprises at least two working electrodes.

[0366] In Example 51, the subject matter of any one or more of Examples 38-50 optionally includes, where the first sensor system comprises at least three working electrodes.

[0367] In Example 52, the subject matter of any one or more of Examples 38-51 optionally includes, where the first sensor system further comprises a counter electrode.

[0368] In Example 53, the subject matter of any one or more of Examples 38-52 optionally includes, where the first sensor system further comprises two counter electrodes.

[0369] In Example 54, the subject matter of any one or more of Examples 38-53 optionally includes, where the first sensor system further comprises a second reference electrode.

[0370] In Example 55, the subject matter of any one or more of Examples 38-54 optionally includes at least one interconnect extending between the first side of the substrate and the second side of the substrate, the at least one interconnect in electrical communication with one of the reference electrode or the working electrode.

[0371] In Example 56, the subject matter of any one or more of Examples 38-55 optionally includes, wherein the working electrode and the reference electrode are coplanar with one another.

[0372] In Example 57, the subject matter of any one or more of Examples 38-56 optionally includes where the working electrode is on a first side of the substrate and the reference electrode is on a second side of the substrate.

[0373] In Example 58, the subject matter of any one or more of Examples 38-57 optionally includes, wherein the working electrode and the reference electrode are on a first side of the substrate.

[0374] Example 59 is a continuous analyte sensor comprising: a planar substrate having a distal portion and a proximal portion connected by a junction, the distal portion and the proximal portion being connected via the junction at an angle of 70 to 110 degrees; a first electrode on the distal portion of the substrate and a first connection pad on the proximal portion, the first electrode and the first connection pad being electrically coupled through a first trace routed through the junction; a second electrode on the distal portion of the substrate and a second connection pad on the proximal portion, the second electrode and the second connection pad being electrically coupled through a second trace routed through the junction; and at least one analyte sensing membrane extending over one or more of the first and second electrodes.

[0375] In Example 60, the subject matter of Example 59 optionally includes, the proximal portion having a width greater than a width of the distal portion.

[0376] In Example 61, the subject matter of any one or more of Examples 59-60 optionally includes, wherein the proximal portion and the distal portion are approximately the same length.

[0377] In Example 62, the subject matter of any one or more of Examples 59-61 optionally includes the proximal portion comprising a folded portion having a first planar portion and a second planar portion folded on top of the first planar portion.

[0378] In Example 63, the subject matter of Example 62 optionally includes, the first connection pad and the second connection pad being on the folded portion.

[0379] In Example 64, the subject matter of any one or more of Examples 62-63 optionally includes the folded portion comprising an interconnect extending between each side of the folded portion, the interconnect being in electrical communication with one of the first connection pad or the second connection pad.

[0380] In Example 65, the subject matter of any one or more of Examples 59-64 optionally includes the proximal portion further comprising a reinforcement material.

[0381] In Example 66, the subject matter of any one or more of Examples 59-65 optionally includes one or more additional electrical elements on the distal portion.

[0382] In Example 67, the subject matter of any one or more of Examples 59-66 optionally includes the first trace and the second trace being routed through an interface.

[0383] In Example 68, the subject matter of any one or more of Examples 59-67 optionally includes, wherein the first electrode and the second electrode are planar electrodes.

[0384] In Example 69, the subject matter of any one or more of Examples 59-68 optionally includes one of the first electrode or the second electrode being a working electrode.

[0385] In Example 70, the subject matter of any one or more of Examples 59-69 optionally includes, where one of the first electrode or the second electrode is a reference electrode.

[0386] In example 71, the subject matter of any one or more of examples 59-70 optionally includes a third electrode on the distal portion.

[0387] In Example 72, the subject matter of Example 71 optionally includes, where the third electrode comprises a working electrode, a reference electrode, or a counter electrode.

[0388] In Example 73, the subject matter of any one or more of Examples 59-72 optionally includes, wherein the first electrode is on a first side of the distal portion and the second electrode is on a second side of the distal portion opposite the first side.

[0389] In Example 74, the subject matter of any one or more of Examples 59-73 optionally includes, wherein the first electrode and the second electrode are coplanar with one another.

[0390] In Example 75, the subject matter of any one or more of Examples 59-74 optionally includes, where the at least one analyte sensing membrane comprises an enzyme layer configured to sense glucose.

[0391] In Example 76, the subject matter of any one or more of Examples 59-75 optionally includes, where the at least one analyte sensing membrane comprises an enzyme layer configured to sense lactate.

[0392] In Example 77, the subject matter of any one or more of Examples 59-76 optionally includes a third electrode, wherein the first electrode and the third electrode are working electrodes, and the at least one analyte sensing membrane includes one or more enzyme layers configured to sense two or more analytes.

[0393] In Example 78, the subject matter of any one or more of Examples 59-77 optionally includes, the planar substrate comprising a tip portion distal to the first electrode and the second electrode.

[0394] Example 79 is a method of making a planar analyte sensor, the method including: layering a first insulating material, a first conductive material, and a second conductive material on a first side of a substrate; selectively removing portions of the first insulating material to expose portions of the first conductive material to form a first electrode; selectively removing portions of the first insulating material to expose portions of the second conductive material to form a second electrode; layering a second insulating material and a third conductive material on a second side of the substrate opposite the first side; selectively removing portions of the third insulating material to expose portions of the third conductive material to form a third electrode; and depositing an analyte sensing membrane on two of the first electrode, the second electrode, or the third electrode.

[0395] In Example 80, the subject matter of Example 79 optionally includes, where depositing the analyte sensing membrane includes jet valve dispensing the analyte sensing membrane.

[0396] In Example 81, the subject matter of any one or more of Examples 79-80 optionally includes where depositing the analyte sensing membrane includes slot die coating.

[0397] In Example 82, the subject matter of any one or more of Examples 79-81 optionally includes, where depositing the analyte sensing membrane includes screen printing.

[0398] In Example 83, the subject matter of any one or more of Examples 79-82 optionally includes where depositing the analyte sensing membrane includes depositing a multi-layer membrane having an enzyme layer containing one or more analyte-sensitive enzymes.

[0399] In Example 84, the subject matter of Example 83 optionally includes an additional enzyme layer containing one or more analyte-sensitive enzymes.

[0400] In Example 85, the subject matter of any one or more of Examples 83-84 optionally includes, where the enzyme layer is configured to detect glucose.

[0401] In Example 86, the subject matter of any one or more of Examples 83-85 optionally includes, where the intermediate layer is configured to detect lactate.

[0402] In Example 87, the subject matter of any one or more of Examples 79-86 optionally includes creating an interconnect through the substrate from the first side to the second side, the interconnect in electrical communication with one of the first electrode, the second electrode, or the third electrode.

[0403] Example 88 is a method of making a plurality of analyte sensors, the method including: generating a plurality of sensor substrates from a sheet of substrate material, each of the plurality of sensor substrates being aligned on the sheet of substrate material; forming a working electrode and a reference electrode on each of the plurality of sensor substrates; and applying an analyte sensing membrane on each of the working electrodes on each of the plurality of sensor substrates.

[0404] In Example 89, the subject matter of Example 88 optionally includes where applying the analyte sensing membrane includes jet valve dispensing.

[0405] In Example 90, the subject matter of any one or more of Examples 88-89 optionally includes where applying the analyte sensing membrane includes slot die coating.

[0406] In Example 91, the subject matter of any one or more of Examples 88-90 optionally includes where applying the analyte sensing membrane includes screen printing.

[0407] In Example 92, the subject matter of any one or more of Examples 88-91 optionally includes singulating the analyte sensors from the sheet of substrate material.

[0408] Example 93 is a method of making an analyte sensor, the method including alternatingly aligning a plurality of insulating layers and a plurality of conductive layers, stacking the plurality of insulating layers and the plurality of conductive layers together, and selectively removing portions of the plurality of insulating layers to expose at least two electrodes.

[0409] In Example 94, the subject matter of Example 93 optionally includes electroplating at least two electrodes.

[0410] In Example 95, the subject matter of any one or more of Examples 93-94 optionally includes rotogravure printing one of the at least two electrodes to form a reference electrode.

[0411] In Example 96, the subject matter of any one or more of Examples 93-95 optionally includes, where exposing the at least two electrodes includes laser skiving.

[0412] In Example 97, the subject matter of any one or more of Examples 93-96 optionally includes singulating the analyte sensor from a plurality of insulating layers and a plurality of conductive layers.

[0413] In Example 98, the subject matter of any one or more of Examples 93-97 optionally includes, where the method is a roll-to-roll method.

[0414] Example 99 is an analyte sensor comprising a sensor substrate, a first electrode mechanically coupled to the sensor substrate, a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, a second electrode mechanically coupled to the sensor substrate, a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, and an analog front-end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode trace, and electrically coupled to the second electrode trace.

[0415] In example 100, the subject matter of example 99 optionally includes the AFE circuit comprising an AFE substrate, the AFE substrate being mechanically coupled to the sensor substrate.

[0416] In Example 101, the subject matter of any one or more of Examples 99 to 100 optionally includes, wherein the AFE circuitry includes an analog-to-digital converter electrically coupled to convert an analog electrical signal generated by the first electrode and the second electrode into a digital signal.

[0417] In Example 102, the subject matter of Example 101 optionally includes an output connector for coupling the analyte sensor to the sensor electronics assembly, wherein the AFE circuit has a first analog input electrically coupled to the first electrode trace, a second analog input electrically coupled to the second electrode trace, and at least one digital output electrically coupled to the output connector.

[0418] In Example 103, the subject matter of Example 102 optionally includes that the first analog input and the second analog input are positioned on a first side of the AFE circuit, and the first side of the AFE circuit is bonded to a sensor substrate.

[0419] In Example 104, the subject matter of any one or more of Examples 99 to 103 optionally includes, wherein the AFE circuit includes a power input, and the analyte sensor further includes a first power conditioning capacitor coupled to the sensor substrate and electrically connected to the power input.

[0420] In example 105, the subject matter of any one or more of examples 99-104 optionally includes a housing mechanically coupled to the sensor substrate, the AFE circuitry being positioned within the housing.

[0421] In Example 106, the subject matter of Example 105 optionally includes the housing being bonded to the sensor substrate using a bonding agent.

[0422] In Example 107, the subject matter of any one or more of Examples 105-106 optionally includes the housing being molded onto the sensor substrate.

[0423] Example 108 is an analyte sensor system comprising: an analyte sensor comprising a sensor substrate, a first electrode mechanically coupled to the sensor substrate, a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, a second electrode mechanically coupled to the sensor substrate, a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode, and an analog front-end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode trace and electrically coupled to the second electrode trace; a sensor electronics assembly; and a connector electrically coupling the analog front-end circuit to the sensor electronics assembly.

[0424] In Example 109, the subject matter of Example 108 optionally includes the connector being a zero insertion force (ZIF) connector.

[0425] In example 110, the subject matter of any one or more of examples 108-109 optionally includes the sensor electronics assembly receiving at least one digital signal from the AFE across the connector.

[0426] In Example 111, the subject matter of any one or more of Examples 108-110 optionally includes the AFE circuit comprising an AFE substrate, the AFE substrate being mechanically coupled to the sensor substrate.

[0427] In Example 112, the subject matter of any one or more of Examples 108 to 111 optionally includes, wherein the AFE circuitry includes an analog-to-digital converter electrically coupled to convert an analog electrical signal generated by the first electrode and the second electrode into a digital signal.

[0428] In Example 113, the subject matter of Example 112 optionally includes an output connector for coupling the analyte sensor to the sensor electronics assembly, wherein the AFE circuit has a first analog input electrically coupled to the first electrode trace, a second analog input electrically coupled to the second electrode trace, and at least one digital output electrically coupled to the output connector.

[0429] In Example 114, the subject matter of Example 113 optionally includes that the first analog input and the second analog input are positioned on a first side of the AFE circuit, and the first side of the AFE circuit is bonded to a sensor substrate.

[0430] In Example 115, the subject matter of any one or more of Examples 108 to 114 optionally includes, wherein the AFE circuit comprises a power input, and the analyte sensor further comprises a first power conditioning capacitor coupled to the sensor substrate and electrically connected to the power input.

[0431] In Example 116, the subject matter of any one or more of Examples 108-115 optionally includes a housing mechanically coupled to the sensor substrate, the AFE circuitry being positioned within the housing.

[0432] In Example 117, the subject matter of Example 116 optionally includes the housing being bonded to the sensor substrate using a bonding agent.

[0433] In Example 118, the subject matter of any one or more of Examples 116-117 optionally includes the housing being molded onto the sensor substrate.

[0434] In Example 119, the subject matter of any one or more of Examples 108 to 118 optionally includes the connector comprising a sensor side contact and an electronics side contact, the sensor side contact and the electronics side contact physically contacting each other so as to electrically couple the analog front-end circuitry to the sensor electronics assembly.

[0435] In Example 120, the subject matter of any one or more of Examples 108-119 optionally includes, where the connector is a non-contact connector.

[0436] In Example 121, the subject matter of Example 120 optionally includes that the connector comprises a sensor side element and an electronic device side element, and the sensor side element and the electronic device side element are positioned to inductively couple the sensor side element and the electronic device side element.

[0437] In Example 122, the subject matter of any one or more of Examples 120-121 optionally includes, where the analyte sensor is configured to receive power from the sensor electronics via a contactless connector.

[0438] Example 123 is a method of providing data from an analyte sensor to sensor electronics, the method including positioning a sensor side element of a non-contact connector and an electronics side element of the non-contact connector to create a wireless connection between the sensor side element and the electronics side element, transmitting power from the sensor electronics to the analyte sensor via the wireless connection, and transmitting a data signal from the analyte sensor to the sensor electronics via the wireless connection.

[0439] In Example 124, the subject matter of Example 123 optionally includes that the sensor electronics are positioned within the electronics unit housing and the method further includes mechanically coupling the electronics unit housing to the analyte sensor, wherein transmission of power from the sensor electronics to the analyte sensor is responsive to the mechanical coupling.

[0440] In Example 125, the subject matter of any one or more of Examples 123-124 optionally includes where the sensor electronics are positioned within the electronics unit housing, and the method further includes mechanically coupling the electronics unit housing to the analyte sensor, wherein transmission of the data signal from the sensor electronics to the analyte sensor is responsive to the mechanical coupling.

[0441] In Example 126, the subject matter of any one or more of Examples 123-125 optionally includes, where the data signal is a digital signal.

[0442] In Example 127, the subject matter of any one or more of Examples 123-126 optionally includes where the data signal is an analog signal.

[0443] The above detailed description may include reference to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are also referred to herein as "examples." Such examples may include elements in addition to those shown or described. However, the present subject matter also contemplates examples in which only those elements shown or described are provided. Moreover, the present subject matter also contemplates examples using any combination or permutation of those elements (or one or more aspects thereof) shown or described with respect to a particular example (or one or more aspects thereof) or with respect to other examples (or one or more aspects thereof) shown or described herein.

[0444] In the event of a conflict of usage between this document and any document incorporated by reference, the usage in this document takes precedence.

[0445] In this document, the terms "a" or "an" are used to include one or more, as is common in patent documents, regardless of other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a non-exclusive, such that "A or B" can include "A but not B," "B but not A," "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, i.e., a system, device, article, composition, formulation, or process that can include elements in addition to those recited after such terms in a claim is still deemed to be within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc., are used merely as labels and are not intended to impose numerical requirements on their objects.

[0446] The method embodiments described herein may be at least partially machine or computer implemented. Some embodiments may include a computer readable medium or machine readable medium encoded with instructions operable to configure an electronic device to perform the methods described in the above embodiments. Such method implementations may include code, such as microcode, assembly language code, high level language code, etc. Such code may include computer readable instructions for performing various methods. The code may form part of a computer program product. Further, in embodiments, the code may be tangibly stored on one or more volatile, non-transitory, or non-volatile tangible computer readable media, such as during execution or at other times. Examples of these tangible computer readable media may include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memory (RAM), read only memory (ROM), etc.

[0447] The above description is intended to be illustrative, not restrictive. For example, the above described embodiments (or one or more aspects thereof) can be used in combination with each other. Other embodiments can be used, such as those by those of ordinary skill in the art upon reviewing the above description. The "Summary" is provided to enable the reader to quickly grasp the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or spirit of the claims. Also, in the above "Detailed Description," various features may be grouped together to streamline the disclosure. This should not be construed as intending that any unclaimed disclosed feature is essential to any claim. Rather, the subject matter of the invention may reside in less than all features of a particular disclosed embodiment. Thus, the following claims are incorporated into the "Detailed Description" as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the present invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. [Explanation of symbols]

[0448] 100 Environment 101 Host 102 Sensor System 104 Analyte Sensors 106 Sensor Electronics 108 Medical Devices 110 Radio communication signals 112 Handheld Smart Devices 114 tablets 116 Smart Pen 118 Computer 120 Wearable Devices 122 Peripheral medical devices 124 Network 126 Server System 128 Remote Terminal 130 Wearable Sensors 132 User Devices 136 Wearable Sensors 200 Medical Device Systems 202 Measurement circuit 204 Processor 206 Command 208 Memory 210 Data Storage 212 Sensors 214 Battery 216 Recharging System 218 Wireless communication circuits 250 peripheral devices 254 Memory Circuit 256 processors 258 Wireless communication circuits 260 Sensors 270 Medical Devices 274 Memory Circuit 276 processors 278 Wireless communication circuits 280 Sensors 282 Treatment Circuit 290 Sensor mounting unit 292 Battery 294 Gate Circuit 308 Adhesive Pad 314 Mounting unit 318 Electronic Equipment Unit 332 Sensing membrane 334 Analyte Sensors 337 Distal end 338 Working electrode 344 Interference Domain 346 Enzyme Domain 348 Resistance Domain 368 Biointerface membrane 370 Drug-releasing membrane 380 working electrode 382 Interference Domain 384 Enzyme Domain 386 Resistance Domain 388 Drug-releasing membrane 400 Assembly 410 Substrate 412 First end 414 Second End 420 Conductive layer 421 Conductive Trace 422 Connector Pad 424 Working electrode 426 Counter Electrode 430 Insulator 431 Opening 440 Reference electrode 500 Sensor Assembly 510 Substrate 512 First end 514 Second End 516 First conductive layer 517 Second Conductive Layer 518 Third Conductive Layer 520 First Conductive Trace 521 Second Conductive Trace 522 Conductive Trace 523 Connector Pad 524 1st connector pad 525 Second Connector Pad 526 Working electrode 527 Counter Electrode 530 First insulating layer 531 Insulating layer 532 Second Insulation Layer 534 Third Insulation Layer 540 Reference electrode 591 Opening 593 Opening 600 Sensor Assembly 602 First Side 604 Second Side 610 Substrate 612 First end 614 Second End 620 Conductive Trace 621 Conductive Trace 622 Connector Pad 623 Connector Pad 624 Working electrode 625 Working electrode 626 Counter Electrode 630 Insulating layer 632 Insulating layer 640 Reference electrode 700 Sensor Assembly 702 First Side 704 Second Side 710 Substrate 712 First end 714 Second End 720 Conductive Trace 721 Second Conductive Trace 722 Connector Pad 724 First Working Electrode 725 Second Working Electrode 726 Counter Electrode 730 Insulating layer 732 Insulation Layer 740 Reference electrode 800 Sensor Assembly 802 First Side 804 Second Side 810 Substrate 812 First end 814 Second End 820 Conductive Trace 821 Conductive Trace 822 Connector Pad 824 First working electrode 825 Second Working Electrode 826 Counter Electrode 830 Insulating layer 832 Second Insulation Layer 840 Reference electrode 900 System 910 First Spool 912 Second Spool 914 3rd spool 916 4th spool 920 Lamination Tool 930 Laser Skiving Station 940 Electroplating bath 950 Rotogravure 1000 Sensor Assembly 1001 sheets 1100 Assembly 1101 Supply flat sheet 1110 Board 1124 First electrode 1126 Second electrode 1130 Insulating layer 1132 Insulating layer 1133 Insulating layer 1134 Insulating layer 1140 Third Electrode 1200 methods 1202 First electrode 1204 First adhesive layer 1206 Board 1210 operation 1226 Electrode 1230 operation 1240 operation 1300 methods 1302 Electrode 1304 Adhesive layer 1306 Substrate Layer 1350 operation 1360 steps 1400 Sensor Assembly 1401 Flat Sheet 1412 First end 1414 Second end 1422 Connector Pad 1424 Electrode 1426 Electrode 1500 Sensor Assembly 1502 First end 1510 Board 1520 First electrode 1521 Sensing area 1530 Second electrode 1531 Sensing area 1540 Third Electrode 1541 Sensing area 1550 Fourth Electrode 1551 Sensing area 1600 Sensor Assembly 1602 First end 1610 Polymer Substrate 1620 First electrode 1621 Sensing area 1630 Second electrode 1631 Sensing area 1640 Third Electrode 1641 Sensing area 1650 4th electrode 1651 Sensing area 1700 Sensor Assembly 1702 First end 1710 PCB 1720 First electrode 1721 Sensing area 1730 Second electrode 1731 Sensing area 1740 Third Electrode 1750 4th electrode 1751 Sensing area 1801 Sensor Assembly 1810 Photoresist insulating polymer substrate 1812 Photoresist part 1820 Wire Electrode 1821 Assembly 1822 Sensing electrode area 1824 Contact area 1830 Push-out operation 1840 UV exposure operation 1850 Resist development operation 1860 Individualized Action 1870 UV light 1880 Slicing Tool 1900 Sensor Assembly 1901 Conductor-coated polymer core 1902 First end 1904 Second End 1910 Polymer Core 1920 Conductive layer 1921 Sensing area 1930 Conductive layer 1931 Sensing area 1940 Insulating dielectric layer 1950 Conductive layer 2000 Analyte Sensor Assembly 2002 First End 2004 Second End 2010 Core 2011 Insulating dielectric layer 2020 First conductive layer 2030 Second conductive layer 2040 Insulation layer 2050 Reference electrode layer 2100 Sensor Assembly 2110 Board 2120 First electrode 2130 Insulating layer 2131 Electrode 2140 Second electrode 2150 Third Electrode 2200 Double-sided coplanar analyte sensor 2200A 1st side 2200B Second Side 2202 Proximal part 2204 Distal part 2205 Substrate 2210 First reference electrode 2212 Reference Electrode Trace 2220 First working electrode 2222 Working electrode trace 2230 Counter electrode 2232 Counter Electrode Trace 2240 Second working electrode 2242 Reference Electrode Trace 2244 Interconnect 2250 Second Reference Electrode 2252 Working Electrode Trace 2260 Third Working Electrode 2262 Working Electrode Trace 2264 Interconnect 2300 Double-sided coplanar analyte sensor 2300A 1st side 2300B Second Side 2302 Proximal part 2304 Distal part 2305 Substrate 2310 First Reference Electrode 2320 Second Reference Electrode 2322 Reference Electrode Trace 2324 Interconnection 2330 Counter electrode 2332 Counter Electrode Trace 2340 First working electrode 2342 Working electrode trace 2350 Second Working Electrode 2352 Working Electrode Trace 2354 First Interconnect 2356 Second Interconnect 2360 Third Working Electrode 2362 Working Electrode Trace 2364 First Interconnect 2366 Interconnection 2400 Double-sided coplanar analyte sensor 2400A 1st Side 2400B Second Side 2402 Proximal part 2404 Distal part 2405 Board 2410 First reference electrode 2412 Reference Electrode Trace 2420 Reference electrode 2422 Reference Electrode Trace 2424 Interconnection 2430 Counter electrode 2432 Counter Electrode Trace 2440 First working electrode 2442 Working Electrode Trace 2450 Second Working Electrode 2452 Working Electrode Trace 2454 Interconnect 2456 Interconnect 2460 Third Working Electrode 2462 Working Electrode Trace 2464 Interconnect 2500 Double-sided coplanar analyte sensor 2500A 1st side 2500B 2nd side 2502 Proximal part 2504 Distal part 2505 Board 2510 Counter electrode 2520 First Reference Electrode 2522 Reference Electrode Trace 2524 Interconnect 2530 Second Reference Electrode 2532 Reference Electrode Trace 2540 First working electrode 2542 Working Electrode Trace 2550 Second Working Electrode 2552 Working Electrode Trace 2554 Interconnect 2556 Interconnect 2560 Third Working Electrode 2562 Working Electrode Trace 2564 Interconnect 2600 Double-sided coplanar analyte sensor 2600A 1st Side 2600B 2nd side 2602 Proximal part 2604 Distal part 2605 Board 2610 Counter electrode 2612 Counter Electrode Trace 2620 First Reference Electrode 2622 Reference Electrode Trace 2624 Interconnect 2630 Second Reference Electrode 2632 Reference Electrode Trace 2634 Interconnect 2640 First working electrode 2642 Working Electrode Trace 2644 Interconnect 2650 Second Working Electrode 2652 Working Electrode Trace 2654 Interconnect 2656 Interconnect 2660 Third Working Electrode 2662 Working Electrode Trace 2664 Interconnect 2700 Double-sided coplanar analyte sensor 2700A 1st Side 2700B Second Side 2702 Proximal part 2704 Distal part 2705 ​​Board 2710 First Reference Electrode 2712 Reference Electrode Trace 2720 ​​Second Working Electrode 2722 Reference Electrode Trace 2730 Counter Electrode 2732 Counter Electrode Trace 2740 First working electrode 2742 Reference Electrode Trace 2750 Second Reference Electrode 2752 Working Electrode Trace 2754 Interaction 2760 Third Working Electrode 2762 Working Electrode Trace 2764 Interconnect 2800 Double-sided coplanar analyte sensor 2800A 1st side 2800B 2nd side 2802 Proximal part 2804 Distal part 2805 Board 2810 First Reference Electrode 2812 Reference Electrode Trace 2820 Second Reference Electrode 2822 Reference Electrode Trace 2824 Interconnect 2830 Counter Electrode 2832 Counter Electrode Trace 2840 First working electrode 2842 Working Electrode Trace 2850 Second Working Electrode 2852 Working Electrode Trace 2854 Interconnect 2856 Interconnect 2860 Third Working Electrode 2862 Working Electrode Trace 2864 Interconnect 2900 Sensor 2902 Distal part 2904 Proximal part 2905 Board 2906 Tip part 2908 Perforation 3000 Sensors 3002 Distal part 3004 Proximal part 3005 Substrate 3006 Tip part 3100 Sensor 3102 Distal part 3104 Proximal part 3105 Substrate 3106 Tip part 3200 Sensor 3202 Distal part 3204 Proximal part 3205 Substrate 3206 Tip part 3300 Sensor 3302 Distal part 3304 Proximal part 3305 Substrate 3306 Tip part 3308 Perforation 3400 Sensor 3402 Distal part 3404 Proximal part 3405 Substrate 3406 Tip part 3407 part 3500 L-shaped sensor 3500A 1st Configuration 3500B 2nd Configuration 3510 Distal part 3512 Electrode 3515 Joint part 3520 Proximal part 3530 parts 3532 Connection Pad 3600 L-shaped sensor 3610 Distal part 3612 First electrode 3614 Second electrode 3615 Joint part 3618 Trace 3620 Proximal part 3625 Connection Pad 3630 Reinforcement material 3700 Cube Sensor 3705 Circuit Board 3710 First working electrode 3720 Second Working Electrode 3730 Reference electrode 3740 Third Working Electrode 3750 4th Working Electrode 3800 Cube Sensor 3850 Circuit Board 4000 ways 4010 Steps 4020 Steps 4030 Steps 4100 Analyte Sensor System 4102 Measurement circuit 4104 Analyte Sensor 4105 processor 4106 Sensor Electronics 4107 Command 4108 Memory 4110 Data Storage 4112 Sensor 4114 Battery 4118 Wireless communication circuit 4120 Sensor Board 4121 Electrode 4122 Electrode 4124 Electrode 4126 Analog Front-End Circuit 4128 Digital Converter 4130 Connector 4132 Conductive Trace 4194 Gate Circuit 4202 Analog Front-End Chip 4208 Components 4300 Analyte Sensor System 4302 Connector 4304 Connector 4306 Electrode Sub-Assembly 4308 Connector part 4320 Sensor Board 4326 Analog Front-End Circuit 4420 Sensor Board 4426 Analog Front-End Circuit 4500 Analyte Sensor System 4506 Electrode Subassembly 4508 Connector part 4510 Chassis 4510' Case 4512 Pad 4520 Sensor Board 4526 Analog Front-End Circuit 4800 Analyte Sensor System 4802 Non-contact connector 4804 Sensor side element 4806 Electronic equipment side elements 5000 Analyte Sensor System 5004 Coil 5006 Analog Sensor 5008 Break 5010 Sensor Electronics 5012 Components 5020 Sensor Board 5022 Electronic equipment side coil 5024 Battery 5026 Analog Front-End Circuit 5030 Organization

Claims

1. 1. A continuous analyte sensor comprising: a substrate having a first side and a second side opposite the first side, the substrate being planar; a first working electrode on the substrate; a second working electrode on the substrate; and a reference electrode on the substrate, wherein the first working electrode, the second working electrode, and the reference electrode are each a planar electrode; at least two of the first working electrode, the second working electrode, or the reference electrode are on the first side of the substrate, and any remaining planar electrodes are on the second side of the substrate; a reference electrode, wherein the at least two of the first working electrode, the second working electrode, and the reference electrode are coplanar with one another; an interconnect extending through the substrate between the first side and the second side, the interconnect being in electrical communication with one of the reference electrode, the first working electrode, or the second working electrode.

2. 2. The continuous analyte sensor of claim 1, wherein the first working electrode and the second working electrode are on the first side of the substrate and the reference electrode is on the second side of the substrate.

3. The continuous analyte sensor of claim 1 , wherein the first working electrode and the second working electrode are coplanar with each other.

4. 3. The continuous analyte sensor of claim 1, wherein the first working electrode and the reference electrode are on the first side of the substrate and the second reference electrode is on the second side of the substrate.

5. The continuous analyte sensor of claim 1 , wherein the first working electrode and the reference electrode are coplanar with each other.

6. The continuous analyte sensor of any one of claims 1 to 5, wherein the first working electrode is spaced distally from the second working electrode on the substrate.

7. The continuous analyte sensor of any one of claims 1 to 6, wherein the first working electrode and the second working electrode each have approximately equal surface areas.

8. The continuous analyte sensor of any one of claims 1 to 7, wherein the reference electrode has a smaller surface area relative to a surface area of ​​either the first working electrode or the second working electrode.

9. The continuous analyte sensor of any one of claims 1 to 8, further comprising a second reference electrode.

10. 10. The continuous analyte sensor of claim 9, wherein the first and second working electrodes are on the first side of the substrate and the first and second reference electrodes are on the second side of the substrate.

11. The continuous analyte sensor of any one of claims 1 to 10, wherein the first reference electrode has a smaller surface area relative to a surface area of ​​the second reference electrode.

12. 12. The continuous analyte sensor of claim 1, further comprising a third working electrode, the third working electrode being coplanar with at least one of the first working electrode, the second working electrode, or the reference electrode.

13. The continuous analyte sensor of claim 12 , wherein the first working electrode, the second working electrode, and the third working electrode are on the first side of the substrate.

14. 14. The continuous analyte sensor of claim 13, wherein the first working electrode is spaced a first distance from the second working electrode on the substrate, and the second working electrode is spaced a second distance from the third working electrode on the substrate.

15. 15. The continuous analyte sensor of claim 14, wherein the first distance and the second distance are approximately equal.

16. 13. The continuous analyte sensor of claim 12, wherein the first working electrode and the second working electrode are on the first side of the substrate and the third working electrode is on the second side of the substrate.

17. 13. The continuous analyte sensor of claim 12, wherein the first working electrode, the second working electrode, and the third working electrode each have an approximately equal surface area.

18. The continuous analyte sensor of any one of claims 1 to 17, further comprising a first counter electrode, said first counter electrode being a planar electrode.

19. 20. The continuous analyte sensor of claim 18, wherein the first counter electrode is coplanar with at least one of the first working electrode, the second working electrode, or the reference electrode.

20. 20. The continuous analyte sensor of claim 18, wherein the first working electrode and the second working electrode are on the first side of the substrate and the reference electrode and the counter electrode are on the second side of the substrate.

21. 21. The continuous analyte sensor of claim 20, wherein the counter electrode is spaced distally from the reference electrode on the substrate.

22. 20. The continuous analyte sensor of claim 18, wherein the counter electrode has a larger surface area than the reference electrode.

23. 20. The continuous analyte sensor of claim 18, further comprising a second counter electrode, the first counter electrode and the second counter electrode each being a planar electrode.

24. The continuous analyte sensor of any one of claims 1 to 23, wherein the first working electrode, the second working electrode, and the reference electrode are aligned longitudinally along the substrate.

25. 25. The continuous analyte sensor of any one of claims 1 to 24, further comprising at least one analyte sensing membrane extending over one or more of the first and second working electrodes.

26. 26. The continuous analyte sensor of claim 25, further comprising at least one analyte sensing membrane comprising an enzyme layer configured to sense glucose.

27. 26. The continuous analyte sensor of claim 25, wherein the at least one analyte sensing membrane comprises an enzyme layer configured to sense lactate.

28. 26. The continuous analyte sensor of claim 25, wherein the at least one analyte sensing membrane is configured to sense two or more analytes.

29. The continuous analyte sensor of any one of claims 1 to 28, wherein the first working electrode, the second working electrode, and the reference electrode each have a boundary on the substrate.

30. The continuous analyte sensor of any one of claims 1 to 29, wherein the substrate comprises a tip portion extending distally from the first working electrode, the second working electrode, and the reference electrode.

31. 31. The continuous analyte sensor of claim 30, wherein the substrate further comprises a tip portion of the substrate that does not include the first working electrode, the second working electrode, and the reference electrode.

32. 31. The continuous analyte sensor of claim 30, wherein the tip portion is perforated.

33. 31. The continuous analyte sensor of claim 30, wherein the tip portion is rounded.

34. 31. The continuous analyte sensor of claim 30, wherein the tip portion comprises a soft material.

35. 31. The continuous analyte sensor of claim 30, wherein the tip portion comprises a cap secured to the substrate at a distal end.

36. 31. The continuous analyte sensor of claim 30, wherein the tip portion is bendable.

37. 37. The continuous analyte sensor of claim 36, wherein the tip portion comprises a recess and a rounded portion, the rounded portion being spaced distally from the recess.

38. A sensor comprising: a substrate having a first side and a second side opposite the first side, the substrate being planar; a first sensor system on the substrate, the first sensor system being a continuous analyte sensor configured to collect a first type of measurement, the first sensor system comprising: A working electrode; a reference electrode on the substrate, the working electrode and the reference electrode each being a planar electrode; a first sensor system comprising: at least one analyte sensing membrane extending over the at least one working electrode; a second sensor system on the substrate, the second sensor system configured to collect a second type of measurement different from the first type of measurement.

39. 40. The sensor of claim 38, wherein the first sensor system comprises an amperometric sensor.

40. 40. The sensor of claim 39, wherein the second sensor system comprises a potentiometric sensor.

41. the second sensor system a first electrode disposed on the substrate; an ionophore disposed on the substrate and configured to selectively transport target ions to or within the first electrode; a second electrode disposed on the substrate.

42. A sensor electronic device, comprising: generating a first signal corresponding to a current response, the current response based at least in part on a reaction at the working electrode corresponding to a concentration of a first analyte; 42. The sensor of claim 41, further comprising sensor electronics configured to generate a second signal corresponding to an electromotive force, the electromotive force being based at least in part on a potential difference generated between the first electrode and the second electrode in response to the ionophore transporting the target ion corresponding to a concentration of a second analyte to the first electrode.

43. 42. The sensor of claim 41, wherein the first electrode of the second sensor system is on the first side of the substrate and the second electrode of the second sensor system is on the second side of the substrate.

44. 42. The sensor of claim 41, wherein the first sensor system is on the first side of the substrate and the second sensor system is on the second side of the substrate.

45. 42. The sensor of claim 41, wherein the first sensor system and the second sensor system are both on the first side of the substrate.

46. The sensor of any one of claims 38 to 45, further comprising a third sensor system.

47. 47. The sensor of claim 46, wherein the third sensor system is configured to collect a third type of measurement different from the first and second types of measurements.

48. 47. The sensor of claim 46, wherein the first sensor system and the third sensor system are amperometric sensors.

49. 47. The sensor of claim 46, wherein the second sensor system and the third sensor system are potentiometric sensors.

50. The sensor of any one of claims 38 to 49, wherein the first sensor system comprises at least two working electrodes.

51. The sensor of any one of claims 38 to 50, wherein the first sensor system comprises at least three working electrodes.

52. The sensor of any one of claims 38 to 51, wherein the first sensor system further comprises a counter electrode.

53. The sensor of any one of claims 38 to 52, wherein the first sensor system further comprises two counter electrodes.

54. The sensor of any one of claims 38 to 53, wherein the first sensor system further comprises a second reference electrode.

55. 55. The sensor of any one of claims 38-54, further comprising at least one interconnect extending between the first side of the substrate and the second side of the substrate, the at least one interconnect in electrical communication with one of the reference electrode or working electrode.

56. The sensor of any one of claims 38 to 55, wherein the working electrode and the reference electrode are coplanar with each other.

57. The sensor of any one of claims 38 to 56, wherein the working electrode is on the first side of the substrate and the reference electrode is on the second side of the substrate.

58. The sensor of any one of claims 38 to 57, wherein the working electrode and the reference electrode are on the first side of the substrate.

59. 1. A continuous analyte sensor comprising: a planar substrate having a distal portion and a proximal portion connected by an interface, the distal portion and the proximal portion being connected via the interface at an angle between 70 and 110 degrees; a first electrode on the distal portion and a first connection pad on the proximal portion of the substrate, the first electrode and the first connection pad being electrically coupled through a first trace routed through the interface portion; a second electrode on the distal portion and a second connection pad on the proximal portion of the substrate, the second electrode and the second connection pad being electrically coupled through a second trace routed through the interface portion; at least one analyte sensing membrane extending over one or more of the first electrode and the second electrode.

60. 60. The continuous analyte sensor of claim 59, wherein the proximal portion has a width that is greater than a width of the distal portion.

61. 61. The continuous analyte sensor of claim 59 or 60, wherein the proximal portion and the distal portion are approximately the same length.

62. 62. The continuous analyte sensor of any one of claims 59 to 61, wherein the proximal portion comprises a folded portion having a first planar portion and a second planar portion folded on top of the first planar portion.

63. 63. The continuous analyte sensor of claim 62, wherein the first connection pad and the second connection pad are on the folded portion.

64. 63. The continuous analyte sensor of claim 62, wherein the folded portion comprises an interconnect extending between each side of the folded portion, the interconnect being in electrical communication with one of the first connection pad or the second connection pad.

65. The continuous analyte sensor of any one of claims 59 to 64, wherein the proximal portion further comprises a stiffening material.

66. The continuous analyte sensor of any one of claims 59 to 65, further comprising one or more additional electrical elements on the distal portion.

67. The continuous analyte sensor of any one of claims 59 to 66, wherein the first trace and the second trace are routed through the interface.

68. 68. The continuous analyte sensor of any one of claims 59 to 67, wherein the first electrode and the second electrode are planar electrodes.

69. The continuous analyte sensor of any one of claims 59 to 68, wherein one of the first electrode or the second electrode is a working electrode.

70. 70. The continuous analyte sensor of any one of claims 59 to 69, wherein one of the first electrode or the second electrode is a reference electrode.

71. The continuous analyte sensor of any one of claims 59 to 70, further comprising a third electrode on the distal portion.

72. 72. The continuous analyte sensor of claim 71, wherein the third electrode comprises a working electrode, a reference electrode, or a counter electrode.

73. 73. The continuous analyte sensor of any one of claims 59 to 72, wherein the first electrode is on a first side of the distal portion and the second electrode is on a second side of the distal portion opposite the first side.

74. 74. The continuous analyte sensor of any one of claims 59 to 73, wherein the first electrode and the second electrode are coplanar with each other.

75. 75. The continuous analyte sensor of any one of claims 59 to 74, wherein the at least one analyte sensing membrane comprises an enzyme layer configured to sense glucose.

76. 76. The continuous analyte sensor of any one of claims 59 to 75, wherein the at least one analyte sensing membrane comprises an enzyme layer configured to sense lactate.

77. a third electrode, the first electrode and the third electrode being working electrodes; 77. The analyte sensing system of any one of claims 59 to 76, wherein the at least one analyte sensing membrane comprises one or more enzyme layers configured to sense two or more analytes.

78. 78. The continuous analyte sensor of any one of claims 59 to 77, wherein the planar substrate comprises a tip portion distal to the first electrode and the second electrode.

79. 1. A method of making a planar analyte sensor, the method comprising: layering a first insulating material, a first conductive material, and a second conductive material on a first side of a substrate; selectively removing portions of the first insulating material to expose portions of a first conductive material to form a first electrode; selectively removing portions of the first insulating material to expose portions of the second conductive material to form a second electrode; layering a second insulating material and a third conductive material on a second side of the substrate opposite the first side; selectively removing portions of the third insulating material to expose portions of the third conductive material to form a third electrode; and depositing an analyte sensing membrane on two of the first electrode, the second electrode, or the third electrode.

80. 80. The method of claim 79, wherein depositing the analyte sensing membrane comprises jet valve dispensing the analyte sensing membrane.

81. 81. The method of claim 79 or 80, wherein depositing the analyte sensing membrane comprises slot die coating.

82. A method according to any one of claims 79 to 81, wherein depositing the analyte sensing membrane comprises screen printing.

83. 83. The method of any one of claims 79 to 82, wherein depositing the analyte sensing membrane comprises depositing a multi-layer membrane having an enzyme layer containing one or more analyte sensitive enzymes.

84. 84. The method of claim 83, further comprising an additional enzyme layer containing one or more analyte-sensitive enzymes.

85. 84. The method of claim 83, wherein the enzyme layer is configured to detect glucose.

86. 84. The method of claim 83, wherein the intermediate layer is configured to detect lactate.

87. 87. The method of any one of claims 79 to 86, further comprising creating an interconnect through the substrate from the first side to the second side, the interconnect in electrical communication with one of the first electrode, the second electrode, or the third electrode.

88. 1. A method of making a plurality of analyte sensors, the method comprising: producing a plurality of sensor substrates from a sheet of substrate material, each of the plurality of sensor substrates being aligned on the sheet of substrate material; forming a working electrode and a reference electrode on each of the plurality of sensor substrates; and applying an analyte sensing membrane over each of the working electrodes on each of the plurality of sensor substrates.

89. 90. The method of claim 88, wherein applying the analyte sensing membrane comprises jet valve dispensing.

90. 90. The method of claim 88 or 89, wherein applying the analyte sensing membrane comprises slot die coating.

91. A method according to any one of claims 88 to 90, wherein applying the analyte sensing membrane comprises screen printing.

92. 92. The method of any one of claims 88-91, further comprising singulating the analyte sensors from the sheet of substrate material.

93. 1. A method of making an analyte sensor, the method comprising: aligning a plurality of insulating layers and a plurality of conductive layers in an alternating manner; laminating the insulating layers and the conductive layers together; and exposing at least two electrodes by selectively removing portions of the plurality of insulating layers.

94. 94. The method of claim 93, further comprising electroplating the at least two electrodes.

95. 95. The method of claim 93 or 94, further comprising rotogravure printing one of the at least two electrodes to form a reference electrode.

96. 96. The method of any one of claims 93 to 95, wherein exposing the at least two electrodes comprises laser skiving.

97. 97. The method of any one of claims 93-96, further comprising singulating the analyte sensor from the plurality of insulating layers and the plurality of conductive layers.

98. The method according to any one of claims 93 to 97, wherein the method is a roll-to-roll method.

99. 1. An analyte sensor comprising: A sensor substrate; a first electrode mechanically coupled to the sensor substrate; a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode; a second electrode mechanically coupled to the sensor substrate; a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode; an analog front-end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode trace, and electrically coupled to the second electrode trace.

100. 100. The analyte sensor of claim 99, wherein the AFE circuitry comprises an AFE substrate, the AFE substrate being mechanically coupled to the sensor substrate.

101. 101. The analyte sensor of claim 99 or 100, wherein the AFE circuitry comprises an analog-to-digital converter electrically coupled to convert an analog electrical signal generated by the first electrode and the second electrode into a digital signal.

102. an output connector for coupling the analyte sensor to a sensor electronics assembly, the AFE circuit further comprising: a first analog input electrically coupled to the first electrode trace; a second analog input electrically coupled to the second electrode trace; 102. The analyte sensor of claim 101, comprising: at least one digital output electrically coupled to the output connector.

103. 103. The analyte sensor of claim 102, wherein the first analog input and the second analog input are positioned on a first side of the AFE circuitry, and the first side of the AFE circuitry is bonded to the sensor substrate.

104. 104. The analyte sensor of any one of claims 99 to 103, wherein the AFE circuit comprises a power input, and the analyte sensor further comprises a first power conditioning capacitor coupled to the sensor substrate and electrically connected to the power input.

105. The analyte sensor of any one of claims 99 to 104, further comprising a housing mechanically coupled to the sensor substrate, the AFE circuitry being positioned within the housing.

106. 106. The analyte sensor of claim 105, wherein the housing is bonded to the sensor substrate using a bonding agent.

107. 106. The analyte sensor of claim 105, wherein the housing is molded onto the sensor substrate.

108. 1. An analyte sensor system comprising:

1. An analyte sensor, comprising: A sensor substrate; a first electrode mechanically coupled to the sensor substrate; a first electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode; a second electrode mechanically coupled to the sensor substrate; a second electrode trace mechanically coupled to the sensor substrate and electrically coupled to the first electrode; an analyte sensor comprising: an analog front-end (AFE) circuit mechanically coupled to the sensor substrate, electrically coupled to the first electrode traces, and electrically coupled to the second electrode traces; a sensor electronics assembly; a connector electrically coupling the analog front end circuitry to the sensor electronics assembly.

109. 109. The analyte sensor system of claim 108, wherein the connector is a zero insertion force (ZIF) connector.

110. 110. The analyte sensor system of claim 108 or 109, wherein the sensor electronics assembly receives at least one digital signal from the AFE across the connector.

111. The analyte sensor system of any one of claims 108 to 110, wherein the AFE circuitry comprises an AFE substrate, the AFE substrate being mechanically coupled to the sensor substrate.

112. 112. The analyte sensor system of any one of claims 108 to 111, wherein the AFE circuitry comprises an analog-to-digital converter electrically coupled to convert an analog electrical signal generated by the first electrode and the second electrode into a digital signal.

113. an output connector for coupling the analyte sensor to a sensor electronics assembly, the AFE circuit further comprising: a first analog input electrically coupled to the first electrode trace; a second analog input electrically coupled to the second electrode trace; 113. The analyte sensor system of claim 112, comprising: at least one digital output electrically coupled to the output connector.

114. 114. The analyte sensor system of claim 113, wherein the first analog input and the second analog input are positioned on a first side of the AFE circuit, and the first side of the AFE circuit is bonded to the sensor substrate.

115. 115. The analyte sensor system of any one of claims 108 to 114, wherein the AFE circuit comprises a power input, and the analyte sensor further comprises a first power conditioning capacitor coupled to the sensor substrate and electrically connected to the power input.

116. The analyte sensor system of any one of claims 108 to 115, further comprising a housing mechanically coupled to the sensor substrate, the AFE circuitry being positioned within the housing.

117. 117. The analyte sensor system of claim 116, wherein the housing is bonded to the sensor substrate using a bonding agent.

118. 117. The analyte sensor system of claim 116, wherein the housing is molded onto the sensor substrate.

119. 119. The analyte sensor system of any one of claims 108 to 118, wherein the connector comprises a sensor contact and an electronics contact, the sensor contact and the electronics contact being in physical contact with each other so as to electrically couple the analog front end circuitry to the sensor electronics assembly.

120. The analyte sensor system of any one of claims 108 to 119, wherein the connector is a contactless connector.

121. 121. The analyte sensor system of claim 120, wherein the connector comprises a sensor side element and an electronics side element, the sensor side element and the electronics side element being positioned to inductively couple the sensor side element and the electronics side element.

122. 121. The analyte sensor system of claim 120, wherein the analyte sensor is configured to receive power from the sensor electronics via the contactless connector.

123. 1. A method for providing data from an analyte sensor to sensor electronics, comprising: Positioning a sensor-side element of a contactless connector and an electronics-side element of the contactless connector to create a wireless connection between the sensor-side element and the electronics-side element; transmitting power from the sensor electronics to the analyte sensor via the wireless connection; transmitting a data signal from the analyte sensor to the sensor electronics via the wireless connection.

124. The sensor electronics are positioned within an electronics unit housing, and the method comprises:

124. The method of claim 123, further comprising mechanically coupling the electronics unit housing to the analyte sensor, wherein the transmission of power from the sensor electronics to the analyte sensor is responsive to the mechanical coupling.

125. The sensor electronics are positioned within an electronics unit housing, and the method comprises:

124. The method of claim 123, further comprising mechanically coupling the electronics unit housing to the analyte sensor, wherein the transmission of the data signal from the sensor electronics to the analyte sensor is responsive to the mechanical coupling.

126. 124. The method of claim 123, wherein the data signal is a digital signal.

127. 124. The method of claim 123, wherein the data signal is an analog signal.

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