title: Anion exchange SPE and liquid chromatography-tandem mass spectrometry in GHB analysis.
abstract: In this study, the extraction of γ-hydroxybutyrate (GHB) from urine using solid-phase extraction (SPE) is described. SPE was performed on anion exchange columns after samples of urine had been diluted with de-ionized water. After application of the diluted samples containing GHB-d(6) as an internal standard, the sorbent was washed with deionized water and methanol and dried. The GHB was eluted from the SPE column with a solvent consisting of methanol containing 6% glacial acetic acid. The eluent was collected, evaporated to dryness, and dissolved in mobile phase (100 μL) for analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in negative multiple reaction monitoring (MRM) mode. Liquid chromatography was performed in gradient mode employing a biphenyl column and a mobile phase consisting of acetontitrile (containing 0.1% formic acid) and 0.1% aqueous formic acid. The total run time for each analysis was less than 5 min. The limits of detection/quantification for this method were determined to be 50 and 100 ng/mL, respectively. The method was found to be linear from 500 ng/mL to 10,000 ng/mL (r(2)>0.995). The recovery of GHB was found to be greater than 75%. In this report, results of authentic urine samples analyzed for GHB by this method are presented. GHB concentrations in these samples were found to be range from less than 500 ng/mL to 5110 ng/mL.
authors: Massachussetts State Police Crime Laboratory, Sudbury, 01776, USA.
authors: Albert A
authors: AA
authors: Elian
authors: Jeffery
authors: J
authors: Hackett
mesh_terms: D019342:Acetic Acid; D000838:Anions / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D053593:Forensic Toxicology; D006801:Humans; D057230:Limit of Detection; D000432:Methanol; D015203:Reproducibility of Results; D012978:Sodium Oxybate / Q000302:isolation & purification / Q000652:urine*; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000838:Anions; D012978:Sodium Oxybate; D019342:Acetic Acid; D000432:Methanol