Abstract: Embodiments described herein relate generally to compositions that include a synthetic redox-active receptor, and in particular to compositions that include a boronic acid based synthetic redox-active receptor which can electrochemically sense a target analyte in a sample solution. A synthetic redox-active receptor can have a salt selected from the group consisting of: wherein the variables L, L?, R, R?, n and X are described herein.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises a biointerface layer which interfaces with a biological fluid containing the analyte to be measured. The biointerface layer can comprises a biointerface polymer, wherein the biointerface polymer comprises polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise a diffusion-resistance layer, which can comprise a base polymer having a lowest Tg of greater than ?50 C.

Abstract: In some embodiments, an electrochemical sensing system includes a working electrode and a reference electrode. At least a portion of the working electrode includes rhodium. An electrical circuit is electronically coupled to the working electrode and the reference electrode. The electrical circuit is configured to bias the working electrode at voltage of less than about 0.4 V which is sufficient to electrochemically decompose a target analyte, and to measure a current corresponding to the concentration of the target analyte. In some embodiments, a biosensing molecule can be disposed on the working electrode and is operative to catalytically decompose a non-electroactive target analyte to yield and an electroactive by-product. In some embodiment, the reference electrode can include rhodium and its oxides.

Abstract: The invention disclosed herein is a device having an analyte sensor, having a working electrode and a membrane disposed over the electrode and methods of making the device. The multilayered membrane is formed by chemically fusing an inner layer of a polyelectrolyte with an outer layer of an ethylenically unsaturated prepolymer through a chain-growth polymerization reaction of an ethylenically unsaturated silicone prepolymer, a hydride silicone prepolymer, a non-silicone ethylenically unsaturated hydrophilic monomer, a filler and a metal catalyst. The silicone composition formed from the reaction mixture restricts diffusion of an analyte through the membrane. More specifically, the membrane formed comprises a restrictive domain that controls the flux of oxygen and glucose through the membrane to the working electrode.

Abstract: In some embodiments, an electrochemical sensing system includes a working electrode and a reference electrode. At least a portion of the working electrode includes rhodium. An electrical circuit is electronically coupled to the working electrode and the reference electrode. The electrical circuit is configured to bias the working electrode at voltage of less than about 0.4 V which is sufficient to electrochemically decompose a target analyte, and to measure a current corresponding to the concentration of the target analyte. In some embodiments, a biosensing molecule can be disposed on the working electrode and is operative to catalytically decompose a non-electroactive target analyte to yield and an electroactive by-product. In some embodiment, the reference electrode can include rhodium and its oxides.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises a biointerface layer which interfaces with a biological fluid containing the analyte to be measured. The biointerface layer can comprises a biointerface polymer, wherein the biointerface polymer comprises polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise a diffusion-resistance layer, which can comprise a base polymer having a lowest Tg of greater than ?50 C.

Abstract: The invention disclosed herein is a device having an analyte sensor, having a working electrode and a membrane disposed over the electrode and methods of using the device. The multilayered membrane is formed by chemically fusing an inner layer of a polyelectrolyte with an outer layer of an ethylenically unsaturated prepolymer through a chain-growth polymerization reaction.

Abstract: Embodiments described herein relate generally to compositions that include a synthetic redox-active receptor, and in particular to compositions that include a boronic acid based synthetic redox-active receptor which can electrochemically sense a target analyte in a sample solution. In some embodiments, a synthetic redox-active receptor can have a composition of formula I: wherein the variables L, R, R?, n and X? are described herein.

Abstract: Embodiments described herein relate generally to compositions that include a synthetic redox-active receptor, and in particular to compositions that include a boronic acid based synthetic redox-active receptor which can electrochemically sense a target analyte in a sample solution. In some embodiments, a synthetic redox-active receptor can have a composition of formula I: wherein the variables L, L?, R, R?, n and X? are described herein.

Abstract: Methods of covalently attaching heparin to a membrane comprising plasma treating the membrane to produce an amino-functionalized membrane; and reacting the amino-functionalized membrane with heparin under conditions in which heparin becomes covalently attached to the amino-functionalized membrane, wherein said heparin is indirectly attached via a spacer to said amino-functionalized membrane and/or said heparin is attached from a single site in said heparin to a single site on said amino-functionalized membrane or to said spacer. Also disclosed are analyte sensors.

Abstract: In some embodiments, an electrochemical sensing system includes a working electrode and a reference electrode. At least a portion of the working electrode includes rhodium. An electrical circuit is electronically coupled to the working electrode and the reference electrode. The electrical circuit is configured to bias the working electrode at voltage of less than about 0.4 V which is sufficient to electrochemically decompose a target analyte, and to measure a current corresponding to the concentration of the target analyte. In some embodiments, a biosensing molecule can be disposed on the working electrode and is operative to catalytically decompose a non-electroactive target analyte to yield and an electroactive by-product. In some embodiment, the reference electrode can include rhodium and its oxides.

Abstract: An electrochemical sensing system includes a working electrode and a reference electrode, which can at least partially be disposed in a housing. At least a portion of the working electrode includes rhodium metal. An electrical circuit is disposed in the housing and configured to be electronically coupled to the electrodes. The electrical circuit is operative to: (a) bias the working electrode at a voltage of less than about 0.4 V, and (b) measure a current corresponding to the concentration of the target analyte. A communications module is electrically coupled to the electrical circuit and configured to display a concentration of the target analyte, and/or communicate data between the electrical circuit and an external device. The electrodes are movable between a first configuration in which the electrodes are substantially disposed inside the housing, and a second configuration in which at least a portion of the electrodes is disposed outside the housing.

Abstract: Embodiments described herein relate generally to compositions that include a synthetic redox-active receptor, and in particular to compositions that include a boronic acid based synthetic redox-active receptor which can electrochemically sense a target analyte in a sample solution. In some embodiments, a synthetic redox-active receptor can have a composition of formula I: wherein the variables L, L?, R, R? n and X are described herein.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises a biointerface layer which interfaces with a biological fluid containing the analyte to be measured. The biointerface layer can comprises a biointerface polymer, wherein the biointerface polymer comprises polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The sensing membrane can also comprise a diffusion-resistance layer, which can comprise a base polymer having a lowest Tg of greater than ?50 C.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.

Abstract: Embodiments of the present invention are directed to an optical sensor capable of measuring two analytes simultaneously with a single indicator system. In preferred embodiments, the sensor comprises a fluorescent dye having acid and base forms that facilitate ratiometric pH sensing, wherein the dye is further associated with a glucose binding moiety and configured to generate a signal that varies in intensity with the concentration of glucose.

Abstract: Analyte sensors having antioxidant protection are disclosed. By combining antioxidant and/or scavenger agents into polymer matrices that contain sensor moieties, the sensor moieties are protected from reactive oxygen species. Also disclosed are methods of making analyte sensors and methods of inhibiting oxidative degradation of sensing components in hydrated, polymerized analyte sensor systems.