A sensitive automated colorimetric method for the determination of serum gamma-glutamyl transpeptidase.
A highly sensitive and accurate automated method using a Technicon Autoanalyzer AAII was developed for the determination of human serum gamma-glutamyl transpeptidase. gamma-L-Glutamyl-p-nitroanilide added as substrate was split to p-nitroaniline and the gamma-glutamyl group was trapped by glycylglycine in Ammediol/HC1 buffer solution. Liberated p-nitroaniline was diazotized and converted by Tsuda Reagent (N,N-(diethyl)-N'-(1-naphthyl) ethylendiamine) to an azo-dye possessing an absorbance maximum at 550 nm. This new method of determination, using the conversion of p-nitroaniline to azo-dye, was found to be 7 times more sensitive as compared to the conventional direct p-nitroaniline determination method [1]. This method requires only 0.1 ml lerum and permits 60 determinations per hour.
D001322:Autoanalysis; D003124:Colorimetry / Q000379:methods; D005069:Evaluation Studies as Topic; D006801:Humans; D007202:Indicators and Reagents; D007700:Kinetics; D008832:Microchemistry; D013997:Time Factors; D005723:gamma-Glutamyltransferase / Q000097:blood* / Q000378:metabolism
D007202:Indicators and Reagents; D005723:gamma-Glutamyltransferase