Miles Inc.

Ibrahim A Ismail

Wen H Wu

Carmine Greene

David W Michaels

Teresa Yip

The invention provides a nonenzymatic method useful for the semiquantitative determination of glucose, a test composition and test device. Glucose concentration in an aqueous test sample can be determined by preparing a test solution by contacting an aqueous test sample and a dihydroxide component, at an initial pH above 6.5, capable of forming a complex with glucose which complex formation releases a proton, and determining the final pH of the test solution. The invention also provides a self-indicating device format which allows the determination of glucose concentration by merely counting the number of pads which have changed color. No comparison to a color chart is required. The glucose test of the present invention is free of the interferences found in enzymatic glucose tests.

Nonenzymatic glucose test

A method and composition for the enzymatic assay of a liquid test sample, such as urine or serum, for a specific analyte, such as glucose. The method utilizes a dry phase test strip comprising a carrier matrix impregnated with a stabilized enzyme reagent composition including an oxidase enzyme, such as glucose oxidase, that is capable of interacting with the analyte of interest; a chromogen that changes color in response to the analyte-oxidase enzyme interaction to reveal the presence and/or concentration of the analyte in the test sample; and a stabilizer, such as a hydrazide, like GIRARD'S Reagent T, or an amino acid, like arginine, or an amino acid derivative, like the tris(hydroxymethyl)aminomethane sale of glutamic acid, to improve the heat stability and shelf life of the dry phase test strip.

Stabilization of oxidase enzyme-based test strips

A method and composition for the enzymatic assay of liquid test sample, such as urine or serum, for a specific analyte, such as glucose. The method utilizes a dry phase test strip comprising a carrier matrix impregnated with a stabilized enzyme reagent composition including an oxidase enzyme, such as glucose oxidase, that is capable of interacting with the analyte of interest; a chromogen that changes color in response to the analyte-oxidase enzyme interaction to reveal the presence and/or concentration of the analyte in the test sample; and a stabilizer, such as a hydrazide, like GIRARD'S Reagent T, or an amino acid, like arginine, or an amino acid derivative, like the tris(hydroxymethyl)aminomethane salt of glutamic acid, to improve the heat stability and shelf life of the dry phase test strip.

A new and improved test device and method of determining the presence and concentration of fructosamines in a test sample. The test device includes a test pad comprising a carrier matrix incorporating an indicator reagent composition capable of interacting with fructosamines to produce a detectable or measurable response. The carrier matrix of the device includes a bibulous matrix, such as filter paper, or a nonbibulous matrix, such as a polymeric film. In addition, a new and improved indicator reagent composition comprising a dye, such as tetrazolium violet; a suitable buffer; and an accelerator compound is incorporated into the carrier matrix to provide a test pad demonstrating sufficient color resolution and having sufficient sensitivity to fructosamines in a test sample. Therefore, a fast, more accurate and trustworthy fructosamine assay of a liquid test sample, such as whole blood or serum, is achieved. The improved method of determining the presence or concentration of fructosamines in a liquid test sample is especially useful in the diagnosis and treatment of diabetes mellitus.

Test device and method of assaying for fructosamines

A stable test device for the determination of a peroxidatively active substance comprising a carrier containing 1,4-diisopropylbenzene dihydroperoxide and a benzidine indicator in a molar ratio of from 0.9 to 3.0. The composition can be incorporated in a carrier matrix along with a ferric chelate to provide ascorbate resistance thereto, which is important in a urine test for occult blood. The test device is stable under storage and heat stress and can be used to prepare a multitest strip containing a glucose test based on a peroxidase/potassium iodide indicator system.

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South Bend, IN, United States of America

Ibrahim A Ismail