Sol-gel molecularly imprinted polymer for selective solid phase microextraction of organophosphorous pesticides.
A sol-gel technique was applied for the preparation of water-compatible molecularly imprinted polymer (MIP) for solid phase microextraction (SPME) using diazinon as template and polyethylene glycol as functional monomer. The MIP-coated fiber demonstrated much better selectivity to diazinon and its structural analogs in aqueous cucumber sample than in distilled water, indicating its potential in real samples. Thanks to its specific adsorption as well as rough and porous surface, the coating revealed rather larger extraction capability than the non-imprinted polymer and commercial fibers. In addition, the fiber exhibited excellent thermal (about 350°C) and chemical stability (organic and inorganic). After optimization of several parameters affecting extraction efficiency, a method based on MIP-SPME combined with gas chromatography was developed for the determination of organophosphorus pesticides (OPPs) in vegetable samples. The limits of detection for the tested OPPs were in the range of 0.017-0.77 μg kg(-1). The proposed method was applied to evaluate OPPs in spiked cucumber, green pepper, Chinese cabbage, eggplant and lettuce samples, and recoveries of 81.2-113.5% were obtained by the standard addition method with three spiking levels in each kind of vegetable.
Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science & Technology, Huazhong Agricultural University, Wuhan 430070, China.
Yu-Long
YL
Wang
Yuan-Li
YL
Gao
Pei-Pei
PP
Wang
Huan
H
Shang
Si-Yi
SY
Pan
Xiu-Juan
XJ
Li
D000327:Adsorption; D002849:Chromatography, Gas; D003976:Diazinon / Q000737:chemistry / Q000302:isolation & purification*; D004785:Environmental Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D057230:Limit of Detection; D054802:Molecular Imprinting; D010575:Pesticides / Q000737:chemistry / Q000302:isolation & purification*; D044367:Phase Transition; D011092:Polyethylene Glycols / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry; D016062:Porosity; D052617:Solid Phase Microextraction / Q000379:methods; D014675:Vegetables / Q000737:chemistry*
D004785:Environmental Pollutants; D010575:Pesticides; D011092:Polyethylene Glycols; D019904:Polymethyl Methacrylate; D003976:Diazinon
Molecularly imprinted polymer; Organophosphorous pesticides; Solid phase microextraction; Sol–gel; Vegetable