An ideal substrate for the measurement of pancreatic amylase?

The advanced knowledge on substrate cleavage by human alpha-amylases promotes the development of chromogenic maltotriosides exclusively cleaved at the aglycone bond. Three essentials are required for this type of binding at the active site of the enzyme: (i) A minimal hydrophobic modification at the ultimate glucose unit to exclude the condensation of reaction products, (ii) a non-ionic substituent in the 2-position of the phenolic chromophore, and (iii) pertinent effectors to accomodate the aglycone at subsite +1. The novel substrate 2-chloro-4-nitrophenyl-alpha-D-maltotrioside (acG3-CNP) is presented as an example together with measurement conditions which allow a direct, sensitive and specific measurement of pancreatic amylase without stoichiometric calculations.