Serum Amyläse and Isoamylase Assay on the Hitachi 705 Automatic Clinical Chemical Analyzer

The precision varied from 1.0 to 2.5% (CV) within-day and from 1.1 to 5.6% (CV) day-to-day. The substrate, /?-nitrophenyl-a-D-maltoheptaoside, was also applied to an automated isoamylase assay. The amylase inhibitor from wheat was used to determine the ratio of pancreatic and salivary amylase activities of serum. About 80% of salivary type amylase was inhibited up to an activity level of 1000 U/l, while Inhibition of pancreatic type amylase activity was only 10—15%. Ratios of pancreatic to salivary amylase from 0.1 to 10 can be evaluated in serum with wheat inhibitor. The precision of the isoamylase determination by the Boehringer amylase method was acceptable.