Enzymatic Detection of Gamma-Hydroxybutyrate Using Aldo-Keto Reductase 7A2

• NCJ Number: 234673
• Journal: Journal of Forensic Sciences Volume: 56 Issue: 3 Dated: May 2011 Pages: 783-787
• Author(s): Kestutis Bendinskas, Ph.D.; Patricia Sattelberg, B.S.; Daniel Crossett, B.S.; Andrew Banyikwa, M.S.; Daniel Dempsey, M.S.; James A. MacKenzie, Ph.D.
• Date Published: May 2011
• Length: 5 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America
• Note: Presented in part at the North East Regional Undergraduate and Graduate Student Sigma Xi Poster Conference at SUNY-Oswego, April 18, 2009 in Oswego, NY.

Annotation

This paper discusses the development of an assay that uses aldo-keto reductase 7A2 (AKR7A2) for the specific determination of gamma-hydroxybutyrate (GHB) in various drinks.

Abstract

Gamma-hydroxybutyrate (GHB) is a prescribed medication as well as a drug of abuse. Its detection in various matrices for in-field forensic scientists remains a challenge. In the current study, AKR7A2 was purified using Ni-affinity chromatography. The Michaelis-Menten constant for the GHB oxidation reaction was 10 mM, and the minimum detection limit was 4 mM. Ethanol was not a substrate for AKR7A2. In a coupled reaction with NADP(+), phenazine methosulfate (PMS), and 2,6-dichlorophenolindophenol, various beverages (orange juice, milk, soda, and numerous alcoholic drinks) containing GHB turned from blue to light yellow. In a second coupled reaction where diaphorase replaced PMS, the presence of GHB also caused the expected change of color in various beers. (Published Abstract)