摘要 |
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 <IMAGE> (I) in which R1 is a hydrogen atom, a carboxyl group or an alkyl, phenyl, nitrophenyl, dinitrophenyl, carboxyl-substituted phenyl or trialkylammoniumphenyl radical, R2 is a phenyl, nitrophenyl, biphenylyl or naphthyl radical, R3 is a phenyl, carboxyl-substituted phenyl, carboxyl-substituted hydroxyphenyl or dimethylthiazolyl radical, and A(-) 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 formula are those in which R1 is carboxy, phenyl, 2-carboxy, phenyl, 2-carboxyphenyl, 4-carboxyphenyl, 2,4-dinitrophenyl or 4-trimethylammoniumphenyl, R2 is phenyl, and R3 is phenyl or 2-carboxyphenyl; with the proviso that, when R3 is unsubstituted phenyl or 2-carboxyphenyl, R1 may not be unsubstituted phenyl.
|