Department of Chemistry, Faculty of Physics and Chemistry, Alzahra University, P.O. Box 1993891176, Tehran, Iran.
Department of Chemistry, Faculty of Physics and Chemistry, Alzahra University, P.O. Box 1993891176, Tehran, Iran.
J Chromatogr A. 2019 Oct 25;1604:460478. doi: 10.1016/j.chroma.2019.460478. Epub 2019 Aug 23.
In this study, fabrication of a stir bar sorbent is presented by electropolymerization of pyrrole via cyclic voltametry for the first time. The fabricated stir bar was applied as an efficient sorbent for extraction and pre-concentration of trace amounts of estradiol in urine samples through stir bar sorptive extraction (SBSE) method followed by gas chromatography-flame ionization detector. For this purpose, first the surface of stainless steel rod was modified by hyroxide functional group. Then electropolymerization of pyrrole monomers took place on the surface of functionalized steel rod under the optimized conditions including pyrrole concentration of 0.03 mol L, equal concentration ratio of pyrrole to sodium dodecyl sulfate, 10 cycles of cyclic voltammetry and potential scan rate of 10 mV s. Characterization of the produced sorbent was confirmed by scanning electron microscope imaging and energy-dispersive X-ray and infrared spectroscopy. Evantually, under the optimized conditions, the stir bar sorbent was used for extraction of estradiol from human urine samples. The presented SBSE method showed a good linearity range of 50-700 ng mL with coefficient of determination 0.9910, limit of detection 10 ng mL and theoretical limit of quantification 33 ng mL. Moreover, better enrichment factor (87) and extraction recovery (43%) were obtained using the fabricated stir bar compared with two commercial stir bars for estradiol. The intra- and inter-bar relative recoveries were obtained 92.0% and their coefficient of variations were less than 5.4%.
本研究首次通过循环伏安法电聚合吡咯制备了搅拌棒吸附剂。制备的搅拌棒通过搅拌棒吸附萃取（SBSE）方法作为有效吸附剂，用于萃取和预浓缩尿液样品中的痕量雌二醇，然后通过气相色谱-火焰离子化检测器进行分析。为此，首先通过羟基官能团对不锈钢棒的表面进行改性。然后在优化条件下，在功能化钢棒表面上发生吡咯单体的电聚合，优化条件包括 0.03 mol L 的吡咯浓度、吡咯与十二烷基硫酸钠的等浓度比、10 个循环的循环伏安法和 10 mV s 的电位扫描速率。通过扫描电子显微镜成像、能谱和红外光谱对所制备的吸附剂进行了表征。最终，在优化条件下，搅拌棒吸附剂用于从人尿液样品中萃取雌二醇。所提出的 SBSE 方法具有良好的线性范围，50-700 ng mL，相关系数为 0.9910，检测限为 10 ng mL，理论定量限为 33 ng mL。此外，与两种用于雌二醇的商业搅拌棒相比，所制备的搅拌棒具有更好的富集因子（87）和萃取回收率（43%）。内标和内标之间的相对回收率分别为 92.0%，其变异系数小于 5.4%。
