Determination of Organochlorine and Organophosphorus Pesticide Residues in Vegetables by Gas Chromatography Coupled with Solid phase Microextraction Fiber Based on Allyl-o-cucurbit£Û7£Ýuril

KeyWord:allyl-o-cucurbit£Û7£Ý uril  solid phase microextraction fiber  gas chromatography  organochlorine pesticide residues  organophosphorus pesticide residues  vegetable samples

Abstract:

      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£Û7£Ýuril(Q7-OCH2CH¡¬CH2) coated solid phase microextraction(SPME) fiber.The PDMS/Q7-OCH2CH¡¬CH2 coated SPME fiber was fabricated with Q7-OCH2CH¡¬CH2 and hydroxyl terminated polydimethylsiloxane(OH-PDMS) as stationary phases and ¦Ã-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 4ª±6%-9ª±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.