UNIT 4.24 Enzymatic Activity of Human Carboxylesterases

  1. Matthew K. Ross,
  2. Abdolsamad Borazjani

Published Online: 1 AUG 2007

DOI: 10.1002/0471140856.tx0424s33

Current Protocols in Toxicology

Current Protocols in Toxicology

How to Cite

Ross, M. K. and Borazjani, A. 2007. Enzymatic Activity of Human Carboxylesterases. Current Protocols in Toxicology. 33:4.24:4.24.1–4.24.14.

Author Information

  1. Mississippi State University, Mississippi State, Mississippi

Publication History

  1. Published Online: 1 AUG 2007
  2. Published Print: AUG 2007


The carboxylesterases (CEs) are hydrolytic enzymes that metabolize xenobiotics that contain ester, thioester, or amide bonds. CEs are ubiquitously expressed but are found in highest concentration in membrane-enriched fractions of the liver. This unit describes assays used to measure the enzymatic activity and tissue distribution of human CEs. Both spectrophotometric and HPLC-based assays are described in detail. Several of these methods are rapid and easy to perform. These methods will be useful to investigators who are interested in studying the metabolism and disposition of esterified drugs and environmental chemicals. Curr. Protoc. Toxicol. 33:4.24.1-4.24.14. © 2007 by John Wiley & Sons, Inc.


  • carboxylesterases;
  • hydrolysis;
  • pesticides;
  • xenobiotic metabolism;
  • liver