UNIT 4.27 Measurement of In Vitro Cytochrome P450 2B6 Activity

  1. Robert L. Walsky,
  2. R. Scott Obach

Published Online: 1 FEB 2009

DOI: 10.1002/0471140856.tx0427s39

Current Protocols in Toxicology

Current Protocols in Toxicology

How to Cite

Walsky, R. L. and Obach, R. S. 2009. Measurement of In Vitro Cytochrome P450 2B6 Activity. Current Protocols in Toxicology. 39:4.27:4.27.1–4.27.11.

Author Information

  1. Pfizer Global Research and Development, Groton, Connecticut

Publication History

  1. Published Online: 1 FEB 2009
  2. Published Print: FEB 2009


Cytochrome P450 2B6 (CYP2B6) is responsible for the metabolism of a number of therapeutically relevant drugs and environmental chemicals. While not as frequently involved in xenobiotic metabolism as other more commonly studied P450 enzymes such as CYP3A, CYP2D6, or CYP2C9, its importance is becoming increasingly realized. Bupropion hydroxylase activity is an excellent indicator of in vitro CYP2B6 activity, and the metabolite formed is easily measured by HPLC/MS/MS. This assay allows the use of very low concentrations of human liver microsomes or recombinant enzyme, and it represents a selective, sensitive approach to assessing in vitro CYP2B6 activity, with minimal sample preparation. Curr. Protoc. Toxicol. 39:4.27.1-4.27.11. © 2009 by John Wiley & Sons, Inc.


  • CYP2B6;
  • P450