A simple and rapid ultra-high-performance liquid chromatography (UHPLC) method for determination of efavirenz (EFV) in plasma was developed and applied in a preclinical pharmacokinetic study. The method involves only addition of acetonitrile to precipitation of plasma proteins followed by solvent evaporation. The mobile phase consisted of methanol, acetonitrile and 0.1 M formic acid (20:50:30) at a flow rate of 0.3 mL/min with run time of 5 min. A CSH C18 column and a UHPLC-UV system operating at 245 nm were used. There was a linear response in the range of 0.078 to 10 μg/mL, and the equation was obtained by weighting (1/x2) with r2 = 0.9965. The pharmacokinetic disposition of EFV was investigated in rabbits (two groups, n = 7) following a single intravenous administration (IV group) at a dose of 2.7 mg/kg and a single oral administration (oral group) of EFV co-administered with lamivudine (3TC) and tenofovir (TNF) at a dose of 50, 25 and 25 mg, respectively. The study demonstrated the applicability of the method for determination of EFV in plasma without interference from other co-administered drugs, and the pharmacokinetic parameters were calculated. The method showed advantages over other methods in the literature, such as simplicity of sample processing and fast results.

中文翻译：

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超高效液相色谱法（UHPLC）结合紫外检测法测定血浆中依法韦仑的简单，快速方法：在临床药代动力学研究中的应用。

建立了测定血浆中依非韦伦（EFV）的简便快速的超高效液相色谱（UHPLC）方法，并将其应用于临床前药代动力学研究。该方法仅包括添加乙腈以沉淀血浆蛋白，然后蒸发溶剂。流动相由甲醇，乙腈和0.1 M甲酸（20:50:30）组成，流速为0.3 mL / min，运行时间为5分钟。使用CSH C18色谱柱和在245 nm下运行的UHPLC-UV系统。线性响应的范围为0.078至10μg/ mL，方程式通过对（1 / x2）进行加权r2 = 0.9965来获得。在以2剂量单次静脉内给药（IV组）后，在兔子（两组，n = 7）中研究了EFV的药代动力学特征。EFV与拉米夫定（3TC）和替诺福韦（TNF）分别以7 mg / kg和单次口服（口服组）联合给药，剂量分别为50、25和25 mg。该研究证明了该方法在血浆中测定EFV的适用性，不受其他共同给药药物的干扰，并计算了药代动力学参数。与文献中的其他方法相比，该方法具有优势，例如样品处理的简便性和快速的结果。