A fast and simple high-performance liquid chromatographic assay for aryl hydrocarbon hydroxylase

A simple high-performance liquid chromatographic method using fluorescence detection of the remaining substrate is described for the determination of benzo[alpha]pyrene hydroxylase activity. This assay is far simpler than the previous ones, as it does not require extraction or centrifugation and the measurement occurs directly after dilution of the total incubation medium. The aryl hydrocarbon hydroxylase (AHH) activities in rat liver microsomes are in agreement with those obtained by radioactive assays. Moreover, this assay allows the routine determination of the AHH activity in animal tissues.