A new fluorimetric method for the determination of gamma-glutamyltransferase activity in blood serum.

Using 7-(gamma-L-glutamyl)-4-methyl-coumarylamide as the fluorogenic substrate a simple and sensitive method for the assay of transferase activity of gamma-glutamyl-transferase in human blood serum and some other biological fluids is described. The substrate was synthesized with a good yield by the King and Kidd method. Close correlation and good agreement was noted between activities measured by the fluorimetric method and by the old colorimetric one in which gamma-L-glutamyl-p-nitroanilide was used.