Method for measuring color change of oxidation-reduction indicator

Patent metadata

Field	Value
Publication number	US-9598715-B2
Application number	US-201214348199-A
Country	US
Kind code	B2
Filing date	Aug 17, 2012
Priority date	Sep 30, 2011
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

Provided is a method for measuring a color change of an oxidation-reduction indicator, which method is applicable to measurement of the cariogenic bacterial count and the like. A color change of an oxidation-reduction indicator is measured by a method for measuring a color change of an oxidation-reduction indicator, the method comprising reacting a test reagent with a test sample and measuring a color change, wherein the test reagent contains an oxidation-reduction indicator, an oxidation-reduction promoter, and a halogen salt.

First claim

The invention claimed is:

1. A method for measuring cariogenic bacterial count in a test sample comprising cariogenic bacteria using a color change of an oxidation-reduction indicator, the method comprising the steps of:
reacting a test reagent with the test sample and measuring the resulting color change by a reflectometer, wherein the test reagent comprises:
resazurin as an oxidation-reduction indicator;
an oxidation-reduction promoter selected from the group consisting of 1-methoxy-5-methylphenazinium methyl sulfate, phenazinium methyl sulfate and phenazine ethosulfate; and
a halogen salt selected from the group consisting of sodium chloride, potassium chloride, sodium bromide and potassium bromide present at a concentration range of from 50 to 200 mM, wherein the method measures the cariogenic bacterial count based on the degree of the color change of said oxidation-reduction indicator.

2. The method according to claim 1 , wherein the measurement is carried out on a test piece comprising a support carrier and an absorption carrier carried by the support carrier, wherein the absorption carrier holds the test reagent.

Assignees

• Nishinaga Eiji
• Suzuki Naho
• Hama Takashi
• Fukuta Isao
• Arkray Inc

Inventors

• Nishinaga Eiji
• Suzuki Naho
• Hama Takashi
• Fukuta Isao

Classifications

• C12Q1/14 Primary

  Streptococcus; Staphylococcus · CPC title

• C12Q1/32

  involving dehydrogenase · CPC title

• G01N2333/9029

  acting on -CH2- groups (1.17) · CPC title

• C12Q1/06 Primary

  Quantitative determination · CPC title

• G01N33/52

  Use of compounds or compositions for colorimetric, spectrophotometric or fluorometric investigation, e.g. use of reagent paper {and including single- and multilayer analytical elements (immunological elements G01N33/54386; involving labelled immunochemicals G01N33/58; for haemoglobin or occult blood G01N33/72)} · CPC title