A biosensor (10) has a hydrogel (30) in a rigid and referably biocompatible enclosure (20). The hydrogel (30) includes an immobilized glucose-binding molecule such as concanavalin A (Con A) and an immobilized hexose saccharide such as a-D-mannopyranoside. The immobilized hexose saccharide competitively binds with free glucose to the glucose-binding molecules, thus changing the number of crosslinks in the hydrogel (30), which changes hydrogel swelling tendency and the pressure of the hydrogel in ...

A sensor that is capable of accurately measuring glucose and other analytes in low oxygen environments is provided. The sensor employs an enzyme-containing membrane comprising a semi-interpenetrating polymer network which is infiltrated by an enzyme. The enzyme-containing membrane increases oxygen transport to the enzyme such that oxygen is not a limiting factor in the oxidation taking place at the enzyme.

Modified water-soluble glucose dehydrogenases having pyrrolo-quinoline quinone as a coenzyme are provided wherein at least one amino acid residue is replaced by another amino acid residue in a specific region. Modified water-soluble PQQGDHs of the present invention have improved affinity for glucose.

The present invention provides a high-performance glucose sensor having excellent storage stability and an improved response characteristic. This sensor comprises: an electrically insulating base plate; an electrode system including at least a working electrode and a counter electrode formed on the base plate; and a reaction layer containing at least pyrrolo-quinoline quinone dependent glucose dehydrogenase, formed in contact with or in the vicinity of the electrode system, and the reaction laye...

Modified water-soluble glucose dehydrogenase having pyrrolo-quinoline quinone as a coenzyme are provided wherein at least one amino acid residue is replaced by another amino acid residue in a specific region. Modified water-soluble PQQGDHs of the present invention have improved thermal stability.

Glucose sensing apparatus for use in biological fluids comprising an electrode and a voltage source connected to the electrode to cause a current to flow therethrough, in which the voltage applied to the electrode is varied in a sweep ranging from a first limit to a second limit and back toward the first limit, and the current at the electrode is integrated with respect to time during at least a portion of the voltage variation selected to produce a total charge sensitive to glucose concentratio...

Glucose identification and determination test. A test strip contains a metering zone, a reaction zone with glucose oxidase, and an indicator zone having at least one indicator signal zone of peroxidase and indicator applied in the form of stripes alternating with untreated intermediate spaces. The metering zone may be impregnated with a colorant, oxidizing, precipitating or buffering agent. The glucose oxidase is applied in an acid solution below the isoelectric point to prevent substrate inhibi...

Glucose in a glucose syrup is transformed into fructose, in high yields, by reaction with glucose isomerizing enzyme derived from micro-organisms which are characterized as having the ability to assimilate xylan to produce a glucose isomerizing enzyme.

An electrochemical apparatus especially applicable for clinical use in determining glucose concentrations in solutions thereof comprising (1) a sample reservoir, (2) a glucose oxidase cell consisting essentially of a well closed at the bottom by a dialysis membrane and containing an anode, glucose oxidase and a buffer solution, (3) a reference cell consisting essentially of a well closed at the bottom by a dialysis membrane and containing an anode and buffer solution, (4) a cathode, (5) means fo...

A reagent and method for the fast (under 5 minutes) determination of glucose in biological fluids by the peroxidase catalyzed oxidation of sulfonated phenyl amines or sulfonated benzidines by hydrogen peroxide formed from the action of glucose oxidase on glucose.