公开(公告)号：JPH1144672A

公开(公告)日：1999-02-16

申请号：JP20318797

申请日：1997-07-29

Applicant: TOA ELECTRONICS

Inventor： KONNO SO ,  KATO EIJI ,  TSUKADA YUICHI ,  HAKETA YASUSHI ,  WADA YUKIHIRO

IPC: G01N33/82 ,  G01N27/42

Abstract: PROBLEM TO BE SOLVED: To obtain an analytical method in which vitamin C can be quantitatively determined precisely by removing the effect of reducing organic substances even when the reducing organic substances other than the vitamin C exist in a sample liquid by a method wherein the sample liquid is brought into contact with a functional group which comprises a distribution capability or an adsorption capability. SOLUTION: In an analytical method for vitamin C by coulometery, a sample liquid which contains the vitamin C is supplied to a detecting cell in which a detecting electrode composed of a conductive porous body and a counter electrode are arranged via a diaphragm, and the vitamin C is quantitatively determined by an electrolytic operation. Then, the sample liquid is brought into contact with a substance into which a functional group comprising a distribution capability or an adsorption capability is introduced, and it is supplied to the detecting cell so as to be quantitatively determined. That is to say, the sample liquid is brought into contact with the substance into which the functional group comprising the distribution capability or the adsorption capability is introduced so as to be pretreated, and reducing organic substances, other than the vitamin C, which are contained in the sample liquid can be removed mostly. A result which is obtained by the chlorometry agrees well with the concentration of vitamin C measured by an indophenol titration method as an official method.