Wako Pure Chemical Industries, Inc.

Kuniaki Tokuda

Kazuhiko Yamanishi

Kazuhito Tanimoto

Fujio Yamazato

Toshiro Hanada

Hiroshi Ogata

Masami Ishihara

Hiroyoshi Nawa

Naoki Teno

Shinzo Kobatake

Taeko Soma

Shizuka Kasahara

Kazuhiko Yamanisi

Tosiro Hanada

Toshihiko Oda

Seiji Morii

Direct bilirubin can be measured stably with high reliability by using bilirubin oxidase or a chemical oxidizing agent of manganese (III) ions, ferricyanide ions or copper ions, or direct bilirubin can also be measured by using as a reaction inhibitor a water-soluble high polymer or a nonionic surfactant having a HLB value of 15 or more.

Method for measuring bilirubin

Total or direct bilirubin can be measured stably with high reliability by using as an oxidizing agent vanadic acid ions or manganese (III) ions, or direct bilirubin can also be measured by using as a reaction inhibitor a water-soluble high polymer or a nonionic surfactant having a HLB value of 15 or more.

A phenol derivative obtained by reacting a carboxylic acid anhydride with a phenol compound, followed by condensation with iminodiacetic acid and formaldehyde, or a salt thereof is effective as an agent for adjusting color forming sensitivity in a colorimetric analysis of metal ions in a fluid such as a living body fluid.

Use of phenol derivative in colorimetric analysis of metal ions

A method for the colorimetic determination of zinc including the steps of:

Colorimetrically measuring method of zinc

.gamma.-GTP activity can be determined easily by using a stabilized substrate solution comprising .gamma.-L-glutamyl-p-nitroanilide and a modified cyclodextrin, together with an acceptor solution containing an acceptor for glutamic acid and measuring p-nitroaniline generated.

Process for determination of .gamma.-GTP activity

A .gamma.-L-glutamyl-4-nitroanilide derivative of the formula: ##STR1## wherein R is a lower hydroxyalkyl group, is suitable as a substrate for determining .gamma.-GTP activity.

.gamma.-L-glutamyl-4-nitroanilide derivatives and process for

A reagent mixture for measuring magnesium comprising Xylylazo Violet I or II as a color producing agent and at least one of sulfide compounds and thioureide compounds, and if necessary one or more surface active agents, can be stored for a long period of time stably and can give a stable color development.

Reagent mixture for measuring magnesium

Peroxidic substances in a sample, e.g. one or more peroxidic substances in fats and oils or in an organic material, lipoperoxides in a living sample, etc. can be determined, directly in a sample or after extracting the lipoperoxides from a living sample with a solvent, by contacting the peroxidic substances with an oxidizable color reagent in the presence of a metallic compound produced from a metal which is able to have two or more valences to produce color, and measuring degree of coloring colorimetrically.

Method for measuring peroxidic substances

Colorimetrical determination of hydrogen peroxide in clinical examinations, food additives analyses and general analyses can be carried out accurately, rapidly and economically by using a composition for producing color producing reagents comprising 4-aminoantipyrine, a N-substituted-3-alkylaniline and a hydrogen peroxide activating agent such as peroxidase, said composition forming a coloring material having excellent sensitivity and color stability in contact with hydrogen peroxide.

Growing community of inventors

Kawagoe, Japan

Kuniaki Tokuda