Analytical element for measurements of enzyme activity
AssigneeFuji Photo Film Co., Ltd.
InventorsYoshikazu Amano, Kazuya Kawasaki, Harumi Katsuyama
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Abstract
A multilayer analytical element for measuring enzyme activity in a liquid sample such as a body fluid which is less affected by intrinsic pyruvic acid contained in the liquid sample is disclosed. The analytical element comprises a support, a reagent layer, an optionally provided other layer, and a porous spreading layer. The reagent layer and/or the optionally provided other layer contain pyruvic acid oxidase. The characteristic feature of the analytical element lies in that the spreading layer has a specific void volume in the range of 3-15 .mu.l/cm.sup.2.
Claims10
A method for quantitatively measuring alanine aminotransferase in a liquid sample selected from the group consisting of serum, plasma and whole blood, said liquid sample containing intrinsic pyruvic acid in an amount of not less than 2 mg/dl which comprises the steps of:
- spotting the liquid sample onto a multilayer analytical element comprising a water-impermeable and light-transmissive support, a reagent layer arranged on the support and a porous spreading layer arranged on the reagent layer, said reagent layer containing pyruvic acid oxidase, peroxidase, and a reagent composition which produces a colored substance by the action of hydrogen peroxide in the presence of peroxidase, said spreading layer having a void volume in the range of 3-15 .mu.l/cm.sup.2, and said reagent layer or said spreading layer containing an alpha-ketoglutaric acid and L-alanine;
- incubating the multilayer analytical element on which the liquid sample has been spotted to produce the colored substance;
- and photometrically measuring the colored substance in the analytical element.
A method for quantitatively measuring aspartic acid aminotransferase in a liquid sample selected from the group consisting of serum, plasma and whole blood, said liquid sample containing intrinsic pyruvic acid in an amount of not less than 2 mg/dl which comprises the steps of:
- spotting the liquid sample onto a multilayer analytical element comprising a water-impermeable and light-transmissive support, a reagent layer arranged on the support and a porous spreading layer arranged on the reagent layer, said reagent layer containing pyruvic acid oxidase, peroxidase, and a reagent composition which produces a colored substance by the action of hydrogen peroxide in the presence of peroxidase, said spreading layer having a void volume in the range of 3-15 .mu.l/cm.sup.2, and said reagent layer or said spreading layer containing an alpha-ketoglutaric acid, L-aspartic acid, and oxaloacetic acid decarboxylate;
- incubating the multilayer analytical element on which the liquid sample has been spotted to produce the colored substance;
- and photometrically measuring the colored substance in the analytical element.
Dependencies are inferred from the claim text.