A simple automated colorimetric method for determination of N-acetyl- beta-D-glucosaminidase

An automated method for the determination of N-acetyl-beta-D-glucosaminidase in serum or plasma using p-nitrophenol (pNP) N-acetyl-beta-D-glucosamine as substrate and a Pye Unicam AURA system is described. Normal samples had activities of 853 +/- 146 (SD) nmol pNP liberated/ml/h, with intra-assay coefficient of variation 1.2% and inter-assay coefficient of variation 1.6%. Inhibition of enzyme activity by heparin in plasma samples can be reversed by the addition of calcium chloride to the buffer.