Monitoring of the interconversion of gamma‐butyrolactone (GBL) to gamma hydroxybutyric acid (GHB) by Raman spectroscopy

Abstract

Gamma-hydroxybutyric acid (GHB) is a drug-of-abuse that has recently become associated with drug-facilitated sexual assault, known as date rape. For this reason the drug is commonly found 'spiked' in alcoholic beverages. When GHB is in solution it may undergo conversion into the corresponding lactone, Gamma-butyrolactone (GBL). Studies have been carried out to determine the detection limits of GHB and GBL in various solutions by Raman spectroscopy and to monitor the interconversion of GHB and GBL in solution with different pH conditions and temperature. In this study, a portable Raman spectrometer was used to study the interconversion of GHB and GBL in water and ethanol solutions as a function of pH, time, and temperature. The aim of this was to determine the optimum pH range for conversion in order to relate this to the pH ranges that the drug is likely to be subjected to, first in spiked beverages and secondly after ingestion in the digestive system. The aim was also to identify a timescale for this conversion in relation to possible scenarios, for example if GHB takes a number of hours to convert to GBL, it is likely for the beverage to be ingested before esterification can take place. GHB and GBL were then spiked into a selection of beverages of known pH in order to study the stability of GHB and GBL in real systems.

Mechanism for rapid growth of organic–inorganic halide perovskite crystals

“…Because the solvents used were specific, the same for all reports, and in all but one report exclude dimethylsulfoxide (DMSO), we reviewed the typical decomposition products for DMF, GBL and DMSO. DMF can decompose into formic acid (FAH) and dimethylamine and GBL can decompose to γ-hydroxybutyric acid (GHB)1314; in contrast, DMSO produces no acidic component upon decomposition. To determine whether this change in solvent composition (and acidity), independent of temperature, could induce the spontaneous crystallization of organic–inorganic halide perovskites, we test the crystallization in both DMF, with the addition of FAH and GBL, with the addition of GHB (the decomposition products).…”

A nitrogen-doped mesopore-dominated carbon electrode allied with anti-freezing EMIBF4–GBL electrolyte for superior low-temperature supercapacitors

“…3b). 33 The peaks at 1070-1110 cm À1 represent the bending vibration of C-4H or C-5H (Fig. 3c), and the signals at 3090-3210 cm À1 stem from the stretching vibrations of C-2H and C-4(5)H on the imidazole ring of the EMI + cation (Fig.…”

Mechanisms for the Specific Properties of γ‐Hydroxybutyrate in Brain

“…Gamma‐butyrolactone (GBL) and 1,4 butanediol have also been identified as endogenous analogues that may serve as precursors for GHB . While 1,4‐butanediol may be oxidized by an alcohol dehydrogenase to produce GHB in the brain, GBL needs to be modified by a peripheral lactonase into GHB before penetrating the brain …”

“…24 While 1,4-butanediol may be oxidized by an alcohol dehydrogenase to produce GHB in the brain, GBL needs to be modified by a peripheral lactonase into GHB before penetrating the brain. [25][26][27] Degradation of GHB may be catalyzed by a GHB dehydrogenase 28,29 coupled to NADP that recycles GHB to SSA. This compound could give either GABA via GABA-T or succinic acid via SSADH.…”