Department of Chemistry, Lorestan University, Khoramabad 6815144316, Iran.
Molecules. 2020 Feb 3;25(3):644. doi: 10.3390/molecules25030644.
The performance of headspace solid-phase microextraction (HS-SPME) was upgraded by easy and low-cost preparation of a new nanocomposite fiber. A polypyrrole/chromium-based metal-organic framework, PPy@MIL-101(Cr), nanocomposite was electrochemically synthesized and simultaneously coated on a steel wire as a microextraction sorbent. The morphology and chemical structure of the prepared nanocomposite was characterized by Fourier-transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) techniques. The microsorbent was used for sampling of methyl--butyl ether (MTBE) in solid samples, through an HS-SPME sampling strategy, followed by GC-FID measurement. The optimal experimental conditions, including extraction temperature, extraction time, and GC desorption conditions, were evaluated and optimized. The proposed procedure showed good sensitivity (limit of detection was 0.01 ng·g) and precision (relative standard deviation was 8.4% for six replicated analyses). The calibration curve was linear over the range of 5-40,000 ng·g, with a correlation coefficient of 0.994. The limit of quantification was 0.4 ng·g. The fabricated fiber exhibited good repeatability and reproducibility for the sampling of MTBE, with average recovery values of 88-114%. The intra-fiber and inter-fiber precisions were found to be 8.4% and 19%, respectively. The results demonstrated the superiority of the PPy@MIL-101(Cr)-coated fiber in comparison with handmade (polypyrrole, PPY) and commercial fibers (polyacrylate, PA; polydimethylsiloxane, PDMS; and divinylbenzene/carboxen/polydimethylsiloxane, DVB/CAR/PDMS) for the analysis of solid samples. The developed method was successfully employed for the analysis of MTBE in different soil samples contaminated by oil products.
通过简便、低成本的方法制备了一种新型纳米复合纤维，从而改进了顶空固相微萃取（HS-SPME）的性能。用电化学合成的方法将聚吡咯/基于铬的金属-有机骨架，PPy@MIL-101（Cr）纳米复合材料同时涂覆在钢丝上作为微萃取吸附剂。通过傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）和能量色散 X 射线分析（EDX）技术对制备的纳米复合材料的形貌和化学结构进行了表征。该微吸附剂通过 HS-SPME 采样策略用于固体样品中甲基叔丁基醚（MTBE）的采样，然后通过 GC-FID 进行测量。评估和优化了最佳实验条件，包括萃取温度、萃取时间和 GC 解吸条件。该方法具有良好的灵敏度（检测限为 0.01ng·g）和精密度（6 次重复分析的相对标准偏差为 8.4%）。校准曲线在 5-40,000ng·g 的范围内呈线性，相关系数为 0.994。定量限为 0.4ng·g。所制备的纤维在 MTBE 的采样中表现出良好的重复性和重现性，MTBE 的平均回收率为 88-114%。纤维内和纤维间的精密度分别为 8.4%和 19%。结果表明，与手工制备的（聚吡咯，PPY）和商业纤维（聚丙烯酸酯，PA；聚二甲基硅氧烷，PDMS；和二乙烯基苯/羧基/聚二甲基硅氧烷，DVB/CAR/PDMS）相比，PPy@MIL-101（Cr）涂层纤维在分析固体样品方面具有优越性。该方法成功用于分析不同受油产品污染的土壤样品中的 MTBE。
