Application of Polymethylphenylsiloxane-coated SPME Fiber for Pesticide Analysis in Vegetables

通过合成羟基聚甲基苯基硅氧烷(PMPS-OH)材料,制备固相微萃取(SPME)纤维涂层。通过与商品化聚二甲基硅氧烷(PdMS)、聚丙烯酸酯(PA)和PdMS/聚二乙烯基苯(dVb)纤维对六六六异构体(α,β,γ,δ-bHC)、ddT及其衍生物(P,P′-ddd,P,P′-ddE,O,P′-ddT,P,P′-ddT)、联苯菊酯、甲氰菊酯、高效氟氯氰菊酯、三氟氯氰菊酯、氯氰菊酯和氰戊菊酯等选定农药萃取效果的比较,所制备的PMPS-OH纤维具有更好的萃取效率。对SPME实验条件进行了研究和优化,测定方法对各种农药的线性范围多在0.01--2 ng/g之间,相应的检出限在0.001--0.05 ng/g范围,回收率在50.5%--103%。方法已被应用于蔬菜样品中农残的检测。Hydroxyl-terminated polymethylphenylsiloxane(PMPS-OH) was synthesized and successfully used as a novel coating for solid-phase microextraction(SPME).PMPS-OH coated fiber was applied to the analysis of pesticides including α,β,γ,δ-BHC,p,p′-DDD,p,p′-DDE,o,p′-DDT,p,p′-DDT,bifenthrin,fenpropathrin,β-cyfluthrin,cyhalothrin,cypermethrin and fenvalerate by SPME-GC-ECD.The extraction efficiencies of the PMPS-OH coated fiber for selected pesticides were found to be higher than those of commercial fibers,such as PDMS,PA and PDMS/DVB.The SPME experimental conditions including stirring rate,extraction temperature and time,were studied,and the optimal conditions were established.The linearity for the target pesticides was from 0.01 to 2 ng/g,and the detection limits were between 0.001 and 0.05 ng/g.The proposed approach was applied to the determination of pesticides in vegetable samples,and the recovery for the pesticides spiked in vegetables at 4 ng/g ranged from 50.5% to 103%.福建省自然科学基金(No.2006J0393);福建省科技计划重点项目(No.2007Y0032

Sol-gel coating for solid phase microextraction and its applications in pesticide residue analysis

利用溶胶-凝胶(SOl-gEl)技术制备固相微萃取(SPME)涂层材料。通过硅醇盐前驱体与涂层聚合物羟基硅油(OH-TSO)的水解共聚的方法,成功地制备了聚二甲基硅氧烷SOl-gEl涂层的SPME萃取头,并以农药的混合标准水溶液为研究对象,用直接-固相微萃取-气相色谱法(gC)对涂层的性能进行考察,制成的萃取头适用于多种农药残留的萃取分离分析。A sol-gel material was successfully applied to preparing a novel coating as a precursor for solid phase microextraction(SPME).A homemade fiber based on solgel polydimethylsiloxane(PDMS) SPME coating was prepared by hydrolysis of alkoxide precursors and subsequent polycondensation with OH-TSO.The characteristics of the new coating were investigated by the analysis of pesticide standard solution mixture in conjunction with gas chromatograph(GC).The proposed fiber presented a wide linear range for target analytes,and exhibited high sensitivity and high thermal stability in applications.福建省自然科学基金(2006J0393);福建省科技计划重点(2007Y0032)项目;福建省南平市科技计划(N2006Z01-1)项目资