A Rapid GC-MS Determination of Gamma-Hydroxybutyrate in Saliva

Abstract

IGHB and its related compounds have been known for years in forensic toxicology because of their illicit use in drug-facilitated sexual assault, and to a lesser extent, as party drugs. A sensitive and specific method for the identification and quantification of gamma-hydroxybutyric acid (GHB) in saliva has been developed using gas chromatography-mass spectrometry with selective ion monitoring mode. One microliter of synthetic saliva was spiked with 1.0 pt of GHB-d6 as the internal standard and 1.0 pL of 1,7-heptanediol as a surrogate spike to all samples. After a silylderivatization, the sample was injected at a split ratio of 10:1. The following ions were monitoring: 233 and 234 for GHB; 239, 240, and 241 for GHB-d6; and 55, 73, and 97 for 1,7-heptanediol. The limit of quantitation was determined to be 0.5 mg/L with a linear dynamic range of 0.5-50.0 mg/L. Quality control samples (5.0, 20.0, and 30.0 rag/L) were prepared for the evaluation of precision. Analytical precision measured by coefficients of variation ranged from 2.1% to 12.50% in both intraday and dayto-day experiments. Surrogate recovery from saliva samples fell in the range of 94.6% to 100% with an average of 98.37% and a corresponding percent relative standard deviation of 1.2%.

Trends in bioanalytical methods for the determination and quantification of club drugs: 2000–2010

“…In addition, there is evidence to suggest that saliva sampling is well reflective of plasma concentrations of some drugs, including amphetamines and GHB. Saliva sampling also shows evidence of drug use quickly after administration (Navarro et al ., 2001; Drummer, 2005; De Paoli and Bell, 2008). Club drug analysis has also attracted the desire to examine some unique matrices including sweat, cerebrospinal fluid, vitreous humor, meconium, placenta, fingernails, bile, brain tissue and bone.…”

“…Several laboratories report quantification of GHB at levels of 0.1 µg/mL or less with matrices such as blood, brain tissue or urine using sample preparations that involve derivatization steps for GC‐MS (Richard et al ., 2005; Brown et al ., 2007; Meng, 2008). A 2008 method for GHB quantification in saliva reports an LOQ of 0.5 µg/mL, while a 2007 GC‐MS method in several matrices (blood, urine, saliva and sweat) reports 0.2 µg/mL LOQ (De Paoli and Bell, 2008; Abanades et al ., 2007). Both of these methods utilize similar derivatization schemes involving 1% trimethylchlorosilane (TCMS).…”

Comparative Toxicity of C60 Aggregates toward Mammalian Cells: Role of Tetrahydrofuran (THF) Decomposition

“…Gas chromatography−mass spectrometry GC/MS (Shimadzu QP5050A, U.S.A.) was used to identify organic residues present in the THF/ n C 60 suspension according to refs and . Acquisition was done in a selected ion-monitoring (SIM) mode (detector voltage, 1.2 kV; solvent cut time, 3 min).…”

Determination of γ‐hydroxybutyric acid in saliva by capillary electrophoresis coupled with contactless conductivity and indirect UV absorbance detectors

“…Different hyphenated techniques with different methodologies are proposed for the determination and quantification of GHB in urine , blood , and saliva . Certainly, one of the suitable methods for the detection of weakly or nonabsorbing small organic and inorganic molecules is CE coupled with a C 4 D. The main advantage of CE‐C 4 D is the miniaturization possibility of the instrument and, therefore, the possibility to conduct measurements on the scene of the crime.…”