... presence of peroxidase and enzyme substrate such as tetramethylbenzidine (TMB) as shown in the following: The distinct ... does not indicate or measure intoxication. There is a possibility that technical or procedure error as well other substances ... 1994, pp 22382-90 2. Bergemeyer, H.U., et.al, Methods of Enzyme Analysis, 3rd ed. Vol. II, ... pp 53-59 4. McCall K.E.L., et.al, Clin. Sce. Vol. 56, 1979, pp 283 ...