The disclosure relates to electrochemical sensors for measuring creatinine and creatine in a patient's blood. More particularly, the disclosure relates to compositions and methods for improving measurement accuracy of electrochemical sensors used for measuring creatinine and creatine.

A device (1) for sensing an analyte, the device (1) comprises at least a sample inlet (10) for receiving a sample, affinity probes (111) selected to have a preferential binding to the analyte, a transducer (11) sensitive to a characteristic of the analyte and/or a label attached to the analyte, the transducer not being a FET transducer, and a desalting unit (13) for desalting the received sample.

Disclosed are multi-enzyme biosensors that are stable at ambient temperature, and methods of making thereof.

Briefly, a carbon working electrode is described that has a plastic substrate of polyethylene, polypropylene, polystyrene, polyvinyl chloride, or polylactic acid, and may be formed into an elongated wire. The carbon material coats the plastic substrate, and may be, for example, graphene, diamagnetic graphite, pyrolytic graphite, pyrolytic carbon, carbon black, carbon paste, or carbon ink, which is aqueously dispersed in an elastomeric material such as polyurethane, silicone, acrylates or acrylics. Optionally, selected additives may be added to the carbon compound prior to it being layered onto the plastic substrate. These additives may, for example, improve electrical conductivity or sensitivity, or act as a catalyst for target analyte molecules.

A method of producing a device includes providing a substrate which has a recess. A multitude of loose particles is introduced into the recess. A first portion of the particles is coated by using a coating process having a depth of penetration which extends from an opening of the recess, along a direction of depth, and into the recess, so that the first portion is connected to form a solidified porous structure. The depth of penetration of the coating process which extends into the recess is set such that a second portion of the particles is not connected by means of the coating, and such that the solidified first portion of the particles is arranged between the second portion of the particles and surroundings of the recess. According to the invention, the second portion of the particles is at least partly removed from the recess.

In various embodiments a molecular circuit is disclosed. The circuit comprises a negative electrode, a positive electrode spaced apart from the negative electrode, and an enzyme molecule conductively attached to both the positive and negative electrodes to form a circuit having a conduction pathway through the enzyme. In various examples, the enzyme is a polymerase. The circuit may further comprise molecular arms used to wire the enzyme to the electrodes. In various embodiments, the circuit functions as a sensor, wherein electrical signals, such as changes to voltage, current, impedance, conductance, or resistance in the circuit, are measured as substrates interact with the enzyme.

A sensor device for determining the concentration of an analyte under in-vivo conditions that includes an electrode system having an electrode with immobilized enzyme molecules and a diffusion barrier that controls diffusion from the exterior of the electrode system to the immobilized enzyme molecules. The diffusion barrier may include an aliphatic polyurethane. A process of manufacturing such a sensor device is also disclosed.

Briefly, a sensor for a continuous biological monitor is provided that has a working electrode with an enhanced carbon-enzyme layer that in one embodiment is made by mixing an aqueous polyurethane emulsion with an acrylic polyol emulsion to make a base emulsion. An enzyme and carbon materials are added to the base emulsion, which is applied to the working electrode and cured. The carbon materials may include carbon and graphite to provide strength, as well as graphene or pyrolytic graphite to provide a desirable electrical resistance for the carbon-enzyme layer. Optionally, other additives can be added to the base emulsion prior to application, such as hydophiles, cross linkers, adding imodeoesters, hydroxysuccimide, carboldilite, melamines, epoxies, benzoyl peroxide or dicumyl peroxide.

A method for fabricating a throughput-scalable sensing system is disclosed. The method includes receiving a first semiconductor wafer and a second semiconductor wafer. The first semiconductor wafer includes a semiconductor substrate and a plurality of sensors disposed in the semiconductor substrate. Each sensor of the plurality of sensors is disposed in a separate semiconductor die of the first semiconductor wafer. The method further includes bonding the first semiconductor wafer to the second semiconductor wafer and preparing the bonded first semiconductor wafer and the second semiconductor wafer for conductive path redistribution. The method further includes forming one or more redistribution paths and dicing an array of semiconductor dies as a group from the plurality of semiconductor dies. The array of semiconductor dies includes a group of sensors associated with the throughput-scalable sensing system.

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.