College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
College of Earth and Environmental Science, Lanzhou University, Lanzhou 730000, China.
J Chromatogr A. 2022 Jul 19;1675:463191. doi: 10.1016/j.chroma.2022.463191. Epub 2022 Jun 1.
γ-Hydroxybutyric acid (GHB), a neurotransmitter or neuromodulator in the human central nervous system, is often abused in drug-facilitated sexual assaults due to its euphoric and sedative effects. While the analysis of GHB has received continuous attention, its inherent characteristics pose challenges. In the current study, capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (CD) was built, and Good's buffers were evaluated as the background electrolytes for CE separation and CD detection. On this basis, a simple and efficient CE-CD method was developed for GHB analysis. Through theoretical discussion and experimental optimization, the separation of GHB and related positional isomers α-hydroxybutyric acid (AHB) and β-hydroxybutyric acid (BHB) was achieved within 4 min using 150 mM 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as the running buffer. Under the optimized condition, the relative standard deviations of migration time and peak area were less than 1.1% and 4.5%, indicating good precision. The CD signal of GHB showed a good linear relationship with GHB concentration in the range of 3-300 µM with a determination coefficient of 0.9997, and the detection limit was calculated to be 0.37 µM based on the signal-to-noise ratio of three. Furthermore, liquid-liquid extraction (LLE) and solid-phase extraction (SPE) were comparatively studied for sample matrix purification. Combined with the optimized SPE procedure, the developed CE-CD method has been successfully applied for the determination of exogenous GHB in spiked beverages and endogenous GHB in human urine.
γ-羟基丁酸（GHB）是一种存在于人类中枢神经系统的神经递质或神经调质，由于其欣快和镇静作用，常被滥用于药物辅助性性侵犯案件中。虽然 GHB 的分析一直受到关注，但由于其固有特性，分析仍具有一定的挑战性。本研究构建了毛细管电泳（CE）与电容耦合非接触式电导检测（CD）联用系统，并评估了 Good 缓冲液作为 CE 分离和 CD 检测的背景电解质。在此基础上，建立了一种简单高效的 CE-CD 方法用于 GHB 分析。通过理论探讨和实验优化，在 150 mM 4-（2-羟乙基）-1-哌嗪乙磺酸（HEPES）作为运行缓冲液的条件下，实现了 GHB 及其相关位置异构体α-羟基丁酸（AHB）和β-羟基丁酸（BHB）在 4 min 内的分离。在优化条件下，GHB 的迁移时间和峰面积的相对标准偏差均小于 1.1%和 4.5%，表明具有良好的精密度。GHB 的 CD 信号在 3-300 µM 范围内与 GHB 浓度呈良好的线性关系，决定系数为 0.9997，根据信噪比计算得到的检测限为 0.37 µM。此外，还比较研究了液液萃取（LLE）和固相萃取（SPE）用于样品基质净化。结合优化的 SPE 程序，所建立的 CE-CD 方法已成功应用于加标饮料中外源性 GHB 和人尿液中内源性 GHB 的测定。
