Determination of gamma-hydroxybutyrate (GHB) and its precursors in blood and urine samples: a salting-out approach.
Gamma-hydroxybutyrate (GHB) is an increasingly popular drug of abuse that causes stimulation, euphoria, anxiolysis or hypnosis, depending on the dose used. Low doses of the drug are used recreationally, and also implicated in drug-facilitated sexual assaults. Because of the unusually steep dose-response curves, accidental GHB overdosing, leading to coma, seizures or death can occur. Being a controlled substance, GHB is often substituted with its non-scheduled precursors gamma-butyrolactone (GBL) and 1,4-butanediol (BD), which are rapidly metabolized into GHB in the body. Here we describe an assay for GHB, GBL and BD in blood and/or urine samples. GHB and BD were extracted from diluted 200 microL aliquots of samples with t-butylmethylether (plus internal standard benzyl alcohol) in test tubes preloaded with NaCl. After acidification and centrifugation the solvent phase was transferred to a test tube preloaded with Na(2)SO(4), incubated for 30 min, centrifuged again, and evaporated in vacuum. The residue was mixed with N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) in acetonitrile, and injected into a GC-MS. When analyzing GBL, the salting-out step was omitted, and analysis was performed with a GC-FID apparatus. As revealed by the validation data this procedure is suitable for quantitative determination of GHB and its precursors in blood and/or urine samples.
Drug Research Unit, Department of Mental Health and Alcohol Research, National Public Health Institute, Mannerheimintie 166, Helsinki, Finland. aino.kankaanpaa@ktl.fi <aino.kankaanpaa@ktl.fi>
Aino
A
Kankaanpää
Raija
R
Liukkonen
Kari
K
Ariniemi
D015107:4-Butyrolactone / Q000097:blood / Q000652:urine; D053000:Analytic Sample Preparation Methods; D002072:Butylene Glycols / Q000097:blood / Q000652:urine; D002492:Central Nervous System Depressants / Q000097:blood* / Q000652:urine*; D053593:Forensic Toxicology / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D015203:Reproducibility of Results; D012965:Sodium Chloride / Q000737:chemistry*; D012978:Sodium Oxybate / Q000097:blood* / Q000652:urine*; D021241:Spectrometry, Mass, Electrospray Ionization; D015813:Substance Abuse Detection / Q000379:methods
D002072:Butylene Glycols; D002492:Central Nervous System Depressants; D012965:Sodium Chloride; D012978:Sodium Oxybate; C039681:1,4-butanediol; D015107:4-Butyrolactone