Department of Chemistry, Faculty of Science, University of Guilan, P.O. Box 1914, Rasht, Iran.
Scientific Research Center, University of Zakho, Zakho, Iraq.
Mikrochim Acta. 2022 Jan 5;189(1):45. doi: 10.1007/s00604-021-05101-8.
The synthesis and utilization of a high porous nanocomposite comprising MIL-53(Al) metal-organic framework (Al-MOF) and graphene nanopowder (GNP) is reported as a fiber coating for headspace solid-phase micro-extraction (HS-SPME) of selected organophosphorus pesticides (OPPs) from apple, potato, grape juice, tomato, and river water. The adsorbed OPPs on the coated fiber were subsequently determined using GC-MS. Several parameters affecting the efficiency of extraction including time and temperature of extraction, desorption condition of extracted analytes, pH and agitation of sample solution, and salt concentration were investigated. The optimum extraction condition was achieved at 70 °C with an extraction time of 40 min, pH = 4-8, and NaCl concentration of 6.0% (w/v). The best condition of desorption were observed at 280 °C for 2.0 min under a flow of helium gas in the GC inlet. Under optimal conditions, the detection limits ranged from 0.2 to 1.5 ng g and the linear ranges between 0.8 and 600 ng g. The proposed method showed very good repeatability with RSD values ranging from 4.5 to 7.3% (n = 5). The relative recoveries were between 88% and 109% at the spiked level of 25.0 ng g for the tomato sample. The fabricated fiber exhibited good enrichment factor (62-195) at optimum condition of HS-SPME. The applied HS-SPME technique is facile, fast, and inexpensive. The thermally stable GNP/Al-MOF exhibited a high sensitivity toward OPPs. So, this nanocomposite can be considered as a sorbent for the micro-extraction of other pesticides in food.
报道了一种高多孔纳米复合材料的合成与利用，该复合材料由 MIL-53(Al) 金属有机骨架（Al-MOF）和石墨烯纳米粉末（GNP）组成，作为一种纤维涂层，用于顶空固相微萃取（HS-SPME）苹果、土豆、葡萄汁、番茄和河水样品中选定的有机磷农药（OPPs）。用 GC-MS 测定涂覆纤维上吸附的 OPPs。考察了影响萃取效率的多个参数，包括萃取时间和温度、萃取物的解吸条件、样品溶液的 pH 和搅拌以及盐浓度。在 70°C 下，萃取时间为 40min，pH=4-8，NaCl 浓度为 6.0%（w/v），达到最佳萃取条件。在氦气流进入 GC 进样口的条件下，最佳解吸条件为 280°C 下 2.0min。在最佳条件下，检测限范围为 0.2-1.5ng·g，线性范围为 0.8-600ng·g。该方法在 25.0ng·g 番茄样品的加标水平下，具有很好的重复性，RSD 值在 4.5-7.3%（n=5）之间。在 25.0ng·g 加标水平下，番茄样品的相对回收率在 88%-109%之间。在 HS-SPME 的最佳条件下，制备的纤维具有良好的富集因子（62-195）。所应用的 HS-SPME 技术简单、快速且经济。热稳定的 GNP/Al-MOF 对 OPPs 具有高灵敏度。因此，这种纳米复合材料可以被认为是食品中其他农药的微萃取的吸附剂。
