| Sulfonyrea is one of the most widely used herbicide because of its high herbicidal activity, broad-spectrum and low toxicity. Sulfonyreas have over 20 species in our country which are usually applied in different areas such as rice, oat, rape, soybean, maize and other types of fields. With the increasing using amount of sulfonyrea herbicides, people focus more attention on the residues in foods, environmental pollution and health hazard. The EU has defined a minimum required performance limits (MRPLs) for sulfonyrea herbicide in drinking water. Japan, USA and EU have defined the MRPLs for sulfonyrea herbicides in the agriculture products in international trade. Pretreatment become the bottle neck of analysis of sulfonyreas because the residues are very low and the sample matrixs are very complex. We have established the methodology of bensulfuron-methyl (BSM), (metsulfuron-methy ) MSM, (nicosulfuron) NS and (tribenuron-methyl)TBM with HPLC and HPLC-MS. A molecularly imprinted polymer (MIP) was prepared with BSM as template molecule and the molecularly imprinted solid phase extract (MISPE) was made using the MIP as sorbent which can selectivity to BSM. A pretreatment methodology based on the MISPE procedure was developed for the determination of BSM, MSM, NS and TBM in the soybean samples and rice samples using HPLC and HPLC-ESI-MS. The study results as follow:The methodology of analysis of herbicides, such as BSM, MSM, NS and TBM was developed using HPLC. This analysis was suitable for BSM, MSM, NS and TBM, the calibration curves were linear in the concentration range from 0.1-7μg.mL-1and the correlation coefficients were well between 0.9997-0.9999. The recoveries were between 70.3-85.6 % in rice sample. The methodology of analysis BSM, MSM, NS and TBM were developed using HPLC-ESI-MS. The MS conditions were as follows: in the positive ionization mode, detecting mass between 200-800 u, capillary voltage 3.93 kV, zone voltage 20 V, drying gas temperature 250 oC, the vaccum 2.6×10-5 mBar, gas flow 4 L/h, the calibration curves were linear in the concentration range from 0.01-0.7μg.mL-1and the correlation coefficients were well between 0.9999-1. The recoveries were between 68.4-88.1 % in the soybean sample and 72.7～88.6 % in the rice samples based on the HPLC-ESI-MS.The soft of Hyperchem 7.0, UV scan and 1H NMR were used to choice the suitable functional monomer of BSM. Optimization for preparation MIP was achieved using the response surface analysis after single-factors test.The results as follow: porogen is 35.14 mL, the ratio of template molecular to function monomer is 0.24, the ratio of function monomer to cross-linker is 0.547. The maximum adsorptions of MIP to BSM are 130.79μmol.g-1 by predicting of response surface analysis, and the actual adsorptions are 129.52μmol.g-1. The adsorption (128.6μmol.g-1) of MIP4 initiated by UV was higher than the adsorption (35.8μmol.g-1) of MIP3 initiated by bath heat(60 oC), which both were prepared using the BSM as template molecule, the MAA as functional monomer, TRIM as the cross-linker, dichloromethane as porogen. The particle size of MIP5 prepared using DVB: TRIM (1:1, mol.L-1 ) as cross-linker more uniformly than MIP4 prepared using only TRIM as cross-linker, and the adsorption (145.3μmol.g-1) of MIP5 higher than the adsorption (128.6μmol.g-1) of MIP4. But the selectivity to BSM of MIP5 were low than MIP4. The reason maybe the structure of DVB can provideπ-πinteractions with the phenyl of BSM, MSM, NS, and TBM. It is important interactions that the double hydrogen bonds of complementary functional groups in the polymer with the template exhibited by the selective study of MIP4 and MIP5. However the shape-selective of four templates with cavity of MIP is less important.The MISPE cartridge was prepared using the MIP as the sorbent. The MIP was prepared using the BSM as template molecule, TRIM: DVB (1:1, mol.L-1) as the cross-linker, dichloromethane (20 mL) as porogen. The MISPE extraction procedure has been optimized. The maximum recoveries of BSM were achieved when 25 mL dichloromethane as percolation solvent, washing solvent is acetonitrile-acetone (1:2, v/v), elution solvent is methanol-water (8:2, v/v). The recoveries of BSM are 99.4 %.The methodology of analysis BSM, MSM, NS and TBM was developed using MISPE-HPLC. The recoveries of BSM using MIP are up to 98.8-100.6 % which higher than ENVITM18-SPE cartridge, and the MSM and NS is higher than ENVITM18-SPE cartridge, too. But the recoveries of TBM are lower than ENVITM18-SPE cartridge. The results of recoveries demonstrate the MIP has the excellent recognition to BSM, MSM and NS than TBM. So this work demonstrates that the MIP can be used successful as adsorbent materials for SPE in soybean and rice samples purification and enrichment.
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