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Enzymatic Detection of Gamma ‐Hydroxybutyrate Using Aldo‐keto Reductase 7A2 * ,†
Author(s) -
Bendinskas Kestutis,
Sattelberg Patricia,
Crossett Daniel,
Banyikwa Andrew,
Dempsey Daniel,
MacKenzie James A.
Publication year - 2011
Publication title -
journal of forensic sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.715
H-Index - 96
eISSN - 1556-4029
pISSN - 0022-1198
DOI - 10.1111/j.1556-4029.2010.01694.x
Subject(s) - gamma hydroxybutyrate , reductase , chemistry , chromatography , orange juice , aldo keto reductase , detection limit , phenethylamine , substrate (aquarium) , enzyme , stereochemistry , biochemistry , food science , biology , pharmacology , ecology
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. We have developed an assay that uses aldo‐keto reductase 7A2 (AKR7A2) for the specific determination of GHB in various drinks. 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.