ISSN: 0022-1198
CODEN: JFSCA
Published Online: 17 December 2003
Page Count: 8

The Extraction and Infrared Identification of Gamma-Hydroxybutyric Acid (GHB) from Aqueous Solutions
Meyn, AW
Drug Enforcement Administration, Western Laboratory, CA

Chappell, JS
Drug Enforcement Administration, Western Laboratory, CA

Ngim, KK
Drug Enforcement Administration, Western Laboratory, CA

(Received 19 May 2003; accepted 24 August 2003)

Abstract

The chemical analysis of gamma-hydroxybutyric acid (GHB) in most forensic laboratories is complicated by the highly polar nature of the GHB molecule, which makes it unsuitable for direct analysis by gas chromatography (GC). Consequently, a popular analytical approach is to convert GHB into the corresponding lactone or a derivative compound that is then identified by mass spectrometry employed in conjunction with GC (GC/MS). An alternative approach is presented here where GHB may be isolated as a free acid specie from complex aqueous solutions employing a liquid-liquid extraction technique. This approach can yield a relatively pure residue of GHB that presents an infrared transmission spectrum that is sufficiently distinct for identification purposes. Infrared spectroscopy (IR) is a very popular technique that is available to most crime laboratories. The liquid-liquid extraction behavior of GHB is examined in detail and the uniqueness of the infrared spectrum is discussed.

Keywords:
forensic science, gamma-hydroxybutyric acid, gamma-hydroxybutyrate, gamma-butyrolactone, GHB, GBL, infrared spectroscopy, liquid-liquid extraction

Paper ID: JFS2003175
DOI: 10.1520/JFS2003175
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