Fan Wenying, He Man, Wu Xiaoran, Chen Beibei, Hu Bin
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, China.
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, China.
J Chromatogr A. 2015 Oct 30;1418:36-44. doi: 10.1016/j.chroma.2015.09.052. Epub 2015 Sep 24.
Graphene oxide (GO) is an ideal adsorbent for polar and less polar compounds due to its hexagonal carbon network structure with oxygen-containing groups, while its strong hydrophilicity and water solubility limited its application in sample pretreatment techniques. Herein, GO was composited with polyethyleneglycol (PEG) or polyaniline (PAN) through intermolecular interactions to improve its stability, and the GO/PEG and GO/PAN composite coated stir bars were prepared by sol-gel technique. Compared with GO/PAN composite and polydimethylsiloxane (PDMS) coated stir bar, the prepared GO/PEG composite coated stir bar exhibited higher extraction efficiency for five fluoroquinolones (FQs). Based on it, a method of GO/PEG composite coated stir bar sorptive extraction (SBSE) combined with high-performance liquid chromatography-fluorescence detector (HPLC-FLD) was proposed. The factors influencing SBSE, such as sample pH, salt effect, stirring rate, extraction time, desorption solvent and desorption time, were optimized, and the analytical performance of the developed SBSE-HPLC-FLD method was evaluated. The limits of detection (LODs) for five FQs were in the range of 0.0045-0.0079μgL(-1), and the enrichment factors (EFs) were in the range of 41.5-65.5-fold (theoretical enrichment factor was 100-fold). The reproducibility was also investigated at concentrations of 0.05μgL(-1) and the relative standard deviations (RSDs, n=6) were found to be in the range of 4.6-12.1%. The proposed method was successfully applied for the determination of FQs in chicken muscle and chicken liver samples.
氧化石墨烯（GO）由于其具有含氧基的六边形碳网络结构，是极性和低极性化合物的理想吸附剂，但其强亲水性和水溶性限制了其在样品预处理技术中的应用。在此，通过分子间相互作用将GO与聚乙二醇（PEG）或聚苯胺（PAN）复合以提高其稳定性，并采用溶胶-凝胶技术制备了GO/PEG和GO/PAN复合涂层搅拌棒。与GO/PAN复合材料和聚二甲基硅氧烷（PDMS）涂层搅拌棒相比，所制备的GO/PEG复合涂层搅拌棒对五种氟喹诺酮类药物（FQs）表现出更高的萃取效率。基于此，提出了一种GO/PEG复合涂层搅拌棒吸附萃取（SBSE）结合高效液相色谱-荧光检测器（HPLC-FLD）的方法。对影响SBSE的因素，如样品pH值、盐效应、搅拌速率、萃取时间、解吸溶剂和解吸时间进行了优化，并评估了所建立的SBSE-HPLC-FLD方法的分析性能。五种FQs的检测限（LODs）在0.0045-0.0079μg L⁻¹范围内，富集因子（EFs）在41.5-65.5倍之间（理论富集因子为100倍）。还在0.05μg L⁻¹浓度下研究了重现性，发现相对标准偏差（RSDs，n = 6）在4.6-12.1%范围内。所提出的方法成功应用于鸡肉和鸡肝样品中FQs的测定。
