烯丙基氧七元瓜环固相微萃取纤维联用气相色谱同时检测蔬菜中的有机氯与有机磷农药残留

Determination of Organochlorine and Organophosphorus Pesticide Residues in Vegetables by Gas Chromatography Coupled with Solid-phase Microextraction Fiber Based on Allyl-o-cucurbit[7]uril

以烯丙基氧七元瓜环(Q7-OCH 2CH‖CH 2)和端羟基聚二甲基硅氧烷(OH-PDMS)为固定相,γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)为偶联试剂,利用溶胶-凝胶方法和自由基交联技术首次制备了PDMS/Q7-OCH 2CH‖CH 2涂层的固相微萃取纤维,建立了PDMS/Q7-OCH 2CH‖CH 2 SPME纤维-气相色谱(GC)/氢火焰离子化检测器(FID)对蔬菜中10种有机氯、有机磷农药残留同时检测的分析方法。结果显示,10种农药的检出限(LOD)为0.01~0.08 mg/kg,定量下限(LOQ)为0.03~0.26 mg/kg,富集倍数为14~67倍。低、中、高3个水平下的平均回收率(n=3)为61.3%~120%,日内及日间精密度(RSD)为4.6%~9.9%(n=5,50 mg/kg)。方法灵敏、简便,可满足蔬菜中有机氯、有机磷农残同时测定的要求。

A gas chromatography with flame ionization detector(GC/FID)was developed for the determination of ten organochlorine and organophosphorus pesticide residues in vegetable samples based on a polydimethylsiloxane(PDMS)/allyl-o-cucurbit[7]uril(Q7-OCH 2CH‖CH 2)coated solid-phase microextraction(SPME)fiber.The PDMS/Q7-OCH 2CH‖CH 2 coated SPME fiber was fabricated with Q7-OCH 2CH‖CH 2 and hydroxyl-terminated polydimethylsiloxane(OH-PDMS)as stationary phases and γ-methacryloxypropyltrimethoxylsilane(KH570)as bridge reagent by sol-gel method and cross-linking technique.The limits of detection of the developed method were in the range of 0.01-0.08 mg/kg for the target pesticide residues,and the limits of quantitation ranged from 0.03 mg/kg to 0.26 mg/kg with an enrichment factor of 14-67 fold.The mean recoveries(n=3)at low,medium and high three spiked levels ranged from 61.3%to 120%,with intra-percision and inter-precision both in the range of 4.6%-9.9%(n=5,spiked 50 mg/kg).The proposed method was simple and sensitive,and was suitable for the simultaneous analysis of organochlorine and organophosphorus pesticide residues in vegetables.