壳聚糖/SiO_2/CdS纳米复合物作为固相萃取膜测定环境水样中的有机磷农药残留

Determination of Organophosphorus Pesticide Residue in Water Sample Using Chitosan/SiO_2/CdS Nanocomposite as SPME Film

采用溶胶——凝胶技术制备了壳聚糖/SiO2/CdS纳米复合材料作为固相微萃取膜,用该萃取膜与气相色谱联用测定环境水样中喹硫磷、甲基对硫磷、对硫磷、二嗪磷等有机磷农药残留。对固相微萃取条件,如萃取温度,萃取时间、萃取的pH值以及萃取时溶液中离子强度等因素进行了优化。在优化的实验条件下,各目标农药样品的检测线性范围为2.0-1000 ng/mL,检出限为1.0-1.7 ng/mL。样品加标回收率为81.13%-105.31%,相对标准偏差（RSD）为2.09%-3.71%。方法具有快速、简便、准确、重现性好的特点。

Chitosan/SiO2/CdS nanocomposite was prepared using a sol-gel technique and used as solid-phase microextraction（SPME） film.A method based on SPME coupled to gas chromatography（GC） for the determination of organophosphorus pesticide（OP） residue including quinalphos,methyl parathion,parathion,diazinon in water sample was developed.The conditions for determination,such as the influence of temperature,time of extraction,pH and ionic strength etc.,were discussed.Under the optimum conditions,the linear range of OP is from 2.0 to 1000 ng/mL and the limit of detection is 1.06~1.73 ng/mL.The average recoveries and relative standard deviation of the pesticides were 81.13%～105.31% and 2.09%~3.71%,respectively.It is concluded that this method is rapid,easy,accurate and reproducible for determining trace OP in water sample.