Preparation of molecularly imprinted solid phase extraction using bensulfuron-methyl imprinted polymer and clean-up for the sulfonylurea-herbicides in soybean

摘要

A pre-treatment methodology based on the molecularly imprinted solid phase extraction (MI-SPE) procedure was developed for the determination of bensulfuron-methyl (BSM),tribenuron-methyl (TBM),metsulfuron-methyl (MSM) and nicosulfuron (NS) in soybean samples.A molecular imprinted polymer (MIP) was prepared by precipitation polymerization using BSM as the template molecule,alpha-methacrylic acid (MAA) as the functional monomer,trimethylolpropane trimethacrylate (TRIM) as the cross-linker and dichloromethane as the porogen.The binding behaviors of the template BSM and its analogues on the MIP were evaluated by high performance liquid chromatography (HPLC).Then,solid phase extraction (SPE) with a BSM molecularly imprinted polymer (BSM-MIP) as adsorbent was investigated and the optimum loading,washing,and eluting conditions for MI-SPE of the selected BSM,MSM,TBM,and NS were established.The optimized MI-SPE procedure was used to extract the sulfonylureas and a high recovery was obtained in the soybean samples.