abstract |
The invention relates to a method for the colorimetric determination of NADH by means of enzymatic oxidation using benzyl-alcohol dehydrogenase with reduction of an aromatic nitroso compound of the formula I to a coloured quinonediimine <IMAGE> in which R<1> is hydrogen, halogen, hydroxyl, alkoxy, aryloxy, alkylthio, arylthio, alkyl or alkylene optionally substituted by carboxyl, PO3H2, dialkylphosphinyl or SO3H, amino, optionally substituted once or twice by alkyl which in turn can optionally be substituted by hydroxyl, PO3H2, SO3H or carboxyl, and R is a radical which generates a colour by electron conjugation with a quinonediimine system. The invention furthermore relates to a corresponding agent and to a chromogenic nitroso compound of the formula I and to the use thereof for the enzymatic colorimetric determination of an analyte. |