Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, NirooHavayii Boulevard, 47416-95447 Babolsar, Iran.
Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, NirooHavayii Boulevard, 47416-95447 Babolsar, Iran.
Talanta. 2017 Oct 1;173:14-21. doi: 10.1016/j.talanta.2017.05.058. Epub 2017 May 22.
A new two-phase hollow fiber-liquid microextraction based on reverse micelle as sensitive and efficient method for the extraction of quercetin in human plasma, onion and tomato samples was developed for the first time. The extraction is based on the solubilization of analyte in the aqueous core of the reverse micelle of cationic cethyltrimethyl ammonium bromide surfactant, CTAB, which are present in the organic phase and are used as acceptor phase in hollow fiber-liquid phase microextraction. Experimental results show that the electrostatic interaction between the oppositely charged surfactant head group present in the reverse micelles and the analyte molecule has a key role in the extraction. Extraction parameters including the organic phase, pH, surfactant concentrations, stirring rate, extraction time, temperature and ionic strength were optimized. The optimum condition is obtained when the variables are set to: pH= 7.5, organic solvent= 1-octanol, CTAB concentration= 7mmolL, stirring rate= 900rpm at room temperature and extraction time= 30min. Under the mentioned condition, the calibration range was found to be linear over 0.5-1000ngmL with the limit of detection of 0.1ngmL. The extraction recovery of 97.4%, with relative standard deviation of 3.5%, was obtained via tree replicated measurements on a 15ngL quercetin standard solution. Finally, the newly developed method was successfully used for the preconcentration and determination of quercetin in plasma, onion and tomato samples.
一种基于反胶束的新型两相中空纤维-液相微萃取法，首次被开发用于灵敏高效地萃取人血浆、洋葱和番茄样品中的槲皮素。该萃取基于分析物在阳离子十六烷基三甲基溴化铵（CTAB）表面活性剂反胶束的水核中的溶解，这些反胶束存在于有机相中，并用作中空纤维-液相微萃取中的接受相。实验结果表明，反胶束中带相反电荷的表面活性剂头基与分析物分子之间的静电相互作用在萃取中起着关键作用。优化了包括有机相、pH 值、表面活性剂浓度、搅拌速度、萃取时间、温度和离子强度在内的萃取参数。当变量设置为 pH=7.5、有机溶剂=1-辛醇、CTAB 浓度=7mmol/L、搅拌速度=900rpm 室温下和萃取时间=30min 时，可获得最佳条件。在所述条件下，校准范围在 0.5-1000ng/mL 之间呈线性，检测限为 0.1ng/mL。通过对 15ng/L 槲皮素标准溶液进行三次重复测量，可获得 97.4%的萃取回收率，相对标准偏差为 3.5%。最后，该新方法成功地用于血浆、洋葱和番茄样品中槲皮素的预浓缩和测定。
