El-Wekil Mohamed M, Ali Hassan Refat H, Marzouk Adel A, Ali Ramadan
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University Assiut Egypt
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al Azhar University Assiut Egypt.
RSC Adv. 2018 Apr 10;8(24):13292-13300. doi: 10.1039/c7ra13719b. eCollection 2018 Apr 9.
An innovative spectrofluorometric method was developed for the analysis of a recently FDA approved anti-hepatitis C velpatasvir (VELP). The developed method was relied on dispersive solid phase extraction (dSPE) using synergistic effect of reduced graphene oxide (RGO) and cobalt hydroxide nanoparticles (CHNPs) in addition to cloud point extraction (CPE) using polyethylene glycol 6000 (PEG 6000) as non-ionic surfactant. This method combines the merits of preconcentration and interferences elimination achieved by dSPE and CPE, respectively. All relevant parameters such as surfactant concentration, ionic strength, pH, incubation time and others were thoroughly investigated and optimized. Fluorometric detection of VELP was carried out at excitation wavelength of 350 nm and emission wavelength of 415 nm. Under the optimum conditions, a linear calibration curve was achieved in the range of 0.5-45 ng mL. Limits of detection (LOD) and quantification (LOQ) based on three and ten times the standard deviation of the blank were 0.040 and 0.112 ng mL, respectively. This method was successfully applied for determination of VELP in real samples such as tablets, human plasma and urine samples with good recoveries.
开发了一种创新的荧光分光光度法，用于分析最近获得美国食品药品监督管理局（FDA）批准的抗丙型肝炎药物维帕他韦（VELP）。所开发的方法依赖于利用氧化石墨烯（RGO）和氢氧化钴纳米颗粒（CHNPs）的协同效应进行分散固相萃取（dSPE），以及使用聚乙二醇6000（PEG 6000）作为非离子表面活性剂进行浊点萃取（CPE）。该方法结合了分别通过dSPE和CPE实现的预浓缩和干扰消除的优点。对所有相关参数，如表面活性剂浓度、离子强度、pH值、孵育时间等进行了全面研究和优化。VELP的荧光检测在激发波长350 nm和发射波长415 nm下进行。在最佳条件下，在0.5 - 45 ng mL范围内获得了线性校准曲线。基于空白标准偏差的三倍和十倍的检测限（LOD）和定量限（LOQ）分别为0.040和0.112 ng mL。该方法成功应用于片剂、人血浆和尿液等实际样品中VELP的测定，回收率良好。
