Rapid determination of enzyme activities of recombinant human cytochromes P450, human liver microsomes and hepatocytes.

Cytochrome P450 (CYP) substrates that yield fluorescent metabolites were used for rapid screening of drug metabolism activities of 13 recombinant human cytochromes P450, human liver microsomes and human hepatocytes. Reproducible results were obtained using a fluorescent plate reader (CytoFluor) more expediently than those generated using conventional HPLC methods. Typically, results for 96 samples were obtained with the plate reader in less than 10 min as opposed to 15-35 min/sample required by conventional HPLC.