Determination of Serum and Urine Amylase with Use of Procion Brilliant Red M-2BS Amylopectin

Abstract

We describe a sensitive, precise assay of serum or urine amylase activity, with use of a new substrate, Procion Brilliant Red M-2BS—Amylopectin. After 0.2 ml of serum or urine is incubated with substrate for 10 min at 37°C, ethylene glycol monomethyl ether is added to precipitate proteins and larger substrate particles. Clarity and chromogenicity of the final solution are not sensitive to small changes in temperature or concentrations of the various reagents. No interferences necessitating preparation of specimen blanks have been encountered. Human salivary amylase, assayed by a reference saccharogenic method, is used for calibration. When read against the resulting curve, normal sera and urines give activities comparable to those obtained with the reference method. Human pancreatic extract, sera and urines from pancreatitis patients, and macroamylasemia serum show higher activities by the proposed method.