The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 1993
Filed:
Feb. 26, 1991
Michael-Harold Town, Oberhausen, DE;
Joachim Siedel, Bernried, DE;
Joachim Ziegenhorn, Starnberg, DE;
Boehringer Mannheim GmbH, Mannheim, DE;
Abstract
A process for the determination of substrate or enzyme activities by the use of a redox reaction as a measurement reaction is carried out in the presence of one or more additionally added tetrazolium salts to remove disturbing substances. The tetrazolium salts have the formula ##STR1## in which R.sup.1 is a hydrogen atom, a carboxyl group or an alkyl, phenyl, nitrophenyl, dinitrophenyl, carboxyl-substituted phenyl or trialkylammoniumphenyl radical, R.sup.2 is a phenyl, nitrophenyl, biphenylyl or naphthyl radical, R.sup.3 is a phenyl, carboxyl-substituted phenyl, carboxyl-substituted hydroxyphenyl or dimethylthiazolyl radical, and A.sup..crclbar. is a monovalent anion. The formazanes formed by reaction with reducing substances do not absorb light at all, or absorb light only to a negligible extent, at the measurement wavelength of the redox reaction. New compounds included within the structural formula are those in which R.sup.1 is carboxy, phenyl, 2-carboxyphenyl, 4-carboxyphenyl, 2,4-dinitrophenyl or 4-trimethylammoniumphenyl, R.sup.2 is phenyl, and R.sup.3 is phenyl or 2-carboxyphenyl; with the proviso that, when R.sup.3 is unsubstituted phenyl or 2-carboxyphenyl, R.sup.1 may not be unsubstituted phenyl.