We demonstrate the suitability of a fast, green, easy-to-perform, and modified sample extraction procedure, i.e., dispersive liquid–liquid microextraction (DLLME) for the determination of efavirenz (EFV) in human plasma. Data acquisition was done by gas chromatography–mass spectrometry (GC–MS) in the selected ion monitoring (SIM) mode. The simplicity of the method lies in, among others, the avoidance of the use of large organic solvent volumes as mobile phases and non-volatile buffers that tend to block the plumbing in high-performance liquid chromatography (HPLC). Chromatographic and mass spectral parameters were optimized using bovine whole blood for matrix matching due to insufficient human plasma. Method validation was accomplished using the United States Food and Drug Administration (USFDA) 2018 guidelines. The calibration curve was linear with a dynamic range of 0.10–2.0 μg/mL and an R² value of 0.9998. The within-run accuracy and precision were both less than 20% at the lower limit of quantification (LLOQ) spike level. The LLOQ was 0.027 μg/mL which compared well with some values but was also orders of magnitude better than others reported in the literature. The percent recovery was 91.5% at the LLOQ spike level. The DLLME technique was applied in human plasma samples from patients who were on treatment with EFV. The human plasma samples gave concentrations of EFV ranging between 0.14–1.00 μg/mL with three samples out of seven showing concentrations that fell within or close to the recommended therapeutic range.

Graphical abstract

中文翻译：

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一种快速筛选分散液-液微萃取-气相色谱-质谱法用于测定人血浆样品中的依法韦仑

我们证明了快速、绿色、易于执行和改进的样品提取程序的适用性，即分散液-液微萃取 (DLLME) 用于测定人血浆中的依法韦仑 (EFV)。数据采集​​在选择离子监测 (SIM) 模式下通过气相色谱-质谱 (GC-MS) 完成。该方法的简单性在于避免使用大体积有机溶剂作为流动相和非挥发性缓冲液，它们往往会阻塞高效液相色谱 (HPLC) 的管道。由于人血浆不足，使用牛全血进行基质匹配优化色谱和质谱参数。方法验证是使用美国食品和药物管理局 (USFDA) 2018 年指南完成的。R ²值为0.9998。在定量下限 (LLOQ) 加标水平下，批内准确度和精密度均小于 20%。LLOQ 为 0.027 μg/mL，与某些值比较好，但也比文献中报道的其他值好几个数量级。LLOQ 加标水平的回收率为 91.5%。DLLME 技术应用于接受 EFV 治疗的患者的人血浆样本。人血浆样品的 EFV 浓度范围在 0.14-1.00 μg/mL 之间，七个样品中的三个样品显示浓度处于或接近推荐的治疗范围。

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