Using ionic liquid monomer to improve the selective recognition performance of surface imprinted polymer for sulfamonomethoxine in strong polar medium.

Molecularly imprinted polymers (MIPs) synthesized by conventional functional monomers have poor specific recognition ability in strong polar solvent, which is not favorable to their applications in separation and analysis. In this work, an ionic liquid functional monomer, 1-allyl-3-vinylimidazolium chloridize, is introduced to prepare sulfamonomethoxine imprinted polymer on the surface of silica carriers in methanol. 1H NMR and 35Cl NMR spectroscopy is performed to discuss the interactions between template and the functional monomer. The rebinding experiments show that the MIP has excellent selectivity towards sulfonamide antibiotic (sulfamonomethoxine, sulfamethoxazole and sulfadiazine) in methanol. From 1H NMR and 35Cl NMR analysis and selective adsorption results, it was inferred that hydrogen bond, electrostatic and π-π interactions are the driving force for the selective recognition of MIP in methanol. Combined solid phase extraction (SPE) with HPLC detection, 98.0-108.0% of sulfamonomethoxine have been extracted by MIP-SPE cartridge from the mixture of sulfamonomethoxine, diphenylamine and N-butylpyridinium chloride. Under optimal condition, the proposed MIP-SPE column can response sulfamonomethoxine linearly in the concentration range from 3.0-1.0×104 μg L-1, and the established MIP-SPE-HPLC system has been successfully applied for extraction and analysis of sulfamonomethoxine in soil and sediment with recoveries ranging from 95.0% to 105.0%.