Eastman-Kodak Company

Richard M Schubert

Charles T Goodhue

John Bruce Findlay

Theodore W Esders

Shirley Y Lynn

Theordore W Esders

An enzymatic method for the analytical determination of creatine kinase in an aqueous liquid such as blood serum is described. The determination is made by measuring an optical density change using the reagents creatine phosphate, adenosine diphosphate, glycerol, glycerol kinase, .alpha.-glycerophosphate oxidase, a chromagen and a mercapto-containing creatine kinase activator. The mercapto-containing creatine kinase activator is added in encapsulated form or in low concentrations so as to preserve the activity of the chromagen.

Composition, analytical element and method for the quantification of

Novel elements for the analysis of aqueous liquids which may contain gentisic acid as an interferent are described. Interference of gentisic acid with the analytical test reactions is reduced by using an organic solvent that dissolves the indicator composition but does not preferentially partition gentisic acid into itself from aqueous liquids.

Reduction of gentisic acid interference in analytical elements

Compositons and multilayer analytical elements comprising lactate oxidase which is substantially free of catalase and preferably produced by Streptococcus faecalis ATCC 12755 are provided for the quantitative analysis of lactic acid or lactate, especially in serum. The lactate oxidase catalyzes the reduction of lactic acid or lactate to pyruvate and hydrogen peroxide and the quantity of lactic acid or lactate is determined by detecting the amount of hydrogen peroxide produced. Preferably, the hydrogen peroxide is detected colorimetrically using a peroxidase-catalyzed detection system.

Growing community of inventors

Spencerport, NY, United States of America

Richard M Schubert