纳米纤维在分析菊酯类农药残留中的应用

以电纺聚苯乙烯纳米纤维作固相萃取材料,对茶叶样品中的拟除虫菊酯农药进行分离富集,用气相色谱-电子捕获器进行检测,并对影响纤维萃取效率的因素进行优化,联苯菊酯、氯菊酯、氰戊菊酯、溴氰菊酯和甲氰菊酯在纳米纤维柱上的最大吸附量分别为7.8、7.5、7.2、6.6、7.0μg/mg,5种农药的3种标准混合液通过纳米纤维小柱后回收率为65.5%～89.0%,RSD为1.2%～3.0%。测定喷洒5种农药后的茶叶样品添加回收率为61.3%～87.1%,RSD为0.9%～2.8%,方法的测定下限为1.0×10-4～1.0×10-2mg/kg。该方法可以满足茶叶中拟除虫菊酯类农药残留检测的要求。

The application of electrospunpolymer nanofibers in determination of five pyrethroid pesticides by gas chromatography

An electrospunpolymer nanofiber was used for materials of solid phase extraction. The pyrethroid pesticides in tea samples were directly extracted with the fiber, and the target compounds were monitored by a gas chromatography with an electron capture detector. Parameters of influencing the performance of the fiber were investigated. Under the optimized conditions, the maximun absorption capacities of the fiber for bifenthrin, permethrin, fenvalerate, deltamethrin, and fenpropathrin were 7.8、7.5、7.2、6.6、7.0 μg/mg, respectively. The five pyrethroids in three mixed standard solutions were extracted by nanofibers. The extraction recoveries were 65.5%～89.0%, RSD 1.2%～3.0%. Tea samples sprayed five pesticides were determined with above method, The extraction recoveries were 61.3%～87.1%,RSD 0.9%～2.8%. The limits of detection (LODs) were in the range of 1.0×10~(-4)～1.0×10~(-2)mg/kg.Compared to C_18sorbent, this method has been used for detection of multiple pyrethroid pesticides in tea samples, and proved to be cheap, simple and consuming less organic solvent.