Validation of determination of human α-amylase activity for patients with pancreatic diseas

Blood α-amylase activity is a key laboratory marker of pancreatic diseases. At the same time, some of the common laboratory methods of its measurement have a number of limitations. Therefore new more effective laboratory methods are currently being developed over those methods that have been already available. The aim of this work was to compare two methods of determination of the activity of total and pancreatic α-amylase in human blood based on using 4,6-ethylidene-(G7)-p-nitrophenyl-(G1)-α,D-maltoheptaoside (EPS-G7) and 2-chloro-4-nitrophenyl-4-O-β-D-galactopyranosylmaltoside (GalG2CNP) as substrates. Blood serum samples from patients with different levels of α-amylase activity were analyzed. The main analytical characteristics of the method with the GalG2CNP substrate were determined using purified α-amylase specimens. A high-sized correlation and high accuracy of the α-amylase isoenzymes activity were observed for the both methods. Therefore, the method for determining the activity of α-amylase using GalG2CNP as a substrate has analytical characteristics similar to the common laboratory method with EPS-G7, but at the same time, the existing advantages allow it to be recommended for wider application in clinical laboratory diagnostics and scientific research