Assay of carboxypeptidase N activity in serum by liquid-chromatographic determination of hippuric acid.

We describe conditions for determining carboxypeptidase N (EC 3.4.17.3) activity by liquid chromatography. Serum (10 microL) is mixed with the artificial substrates hippuryl-L-arginine (30 mmol/L) and hippuryl-L-lysine (100 mmol/L) in 50 mmol/L 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer solution at pH 8.2 and 7.8, respectively. The… CONTINUE READING