GC/MS Profiling of γ-Hydroxybutyrate and Precursors in Various Animal Tissues Using Automatic Solid-Phase Extraction. Preliminary Investigations of Its Potential Interest in Postmortem Interval Determination

• Published in: Analytical chemistry (Washington) 2005-03, Vol.77 (5), p.1354-1360
• Main Authors: Richard, Damien, Ling, Bing, Authier, Nicolas, Faict, Thierry W, Eschalier, Alain, Coudoré, François
• Format: Article
• Language: English
• Subjects: 4-Butyrolactone - analysis; Analytical chemistry; Animal Structures - chemistry; Animals; Butylene Glycols - analysis; Butylene Glycols - blood; Butylene Glycols - metabolism; Calibration; Central Nervous System - chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; gamma-Aminobutyric Acid - analysis; gamma-Aminobutyric Acid - blood; gamma-Aminobutyric Acid - metabolism; Gas chromatographic methods; Gas Chromatography-Mass Spectrometry - methods; Male; Postmortem Changes; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Sensitivity and Specificity; Sodium Oxybate - analysis; Sodium Oxybate - metabolism; Solid Phase Extraction - instrumentation; Solid Phase Extraction - methods; Spectrometric and optical methods; Temperature; Time Factors
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac048471h

To quantify γ-hydroxybutyrate (GHB) and its physiological metabolites, γ-aminobutyric acid (GABA), 1,4-butanediol (1,4-BD), and γ-butyrolactone (GBL) in various animal tissues (kidney, muscle, heart, liver, blood, brain cortex, thalamus, hypothalamus, hippocampus, or pons), an original gas chromatographic/mass spectrometric method with a automated solid-phase extraction by Oasis MCX cartridges on a Gilson Aspec Xli was developed. Using such apparatus allowed the limit of detection (LOD) of target compounds to be significantly lowered (LOD: 0.027, 0.025, and 5.7 μg/mL for GHB, 1,4-BD, and GABA, respectively, in 200 μL or μg of sample). After validation of each analytical step, the satisfactory performances of the apparatus in conjunction with the rapidity and ease of the extraction step make it suitable for simultaneous assay of GHB, 1,4-BD, GBL, and GABA. The method was used to test the correlation between GHB levels in tissues obtained at different times after death of male Sprague−Dawley rats and the postmortem interval. Preliminary results show a linear increase of GHB levels in relation to time of death in thoracic blood and central nervous system of animals kept at 15 and 20 °C.