GC-MS determination of gamma-hydroxybutyric acid (GHB) in blood

A sensitive and specific gas chromatography-mass spectrometer (GC-MS) method using selective ion monitoring (SIM) has been developed for the quantification of gamma-hydroxybutyric acid (GHB) in blood. This method uses liquid-liquid extraction and disilyl-derivatization, without conversion to the gamma-butyrolactone (GBL), followed by GC-MS analysis using GHB-d(6) as the internal standard. The method was linear from 0.1 to 20 mg/dl, and the limit of quantification using 50 mul of blood was determined to be 0.1 mg/dl. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.