Preparation of Isoprocarb Surface Molecular-Imprinted Materials and Its Recognition Character

The silylating agent 3-methacryloxypropyl trimethoxysilane (MPS) was grafted on the surface of silica gel particles, then the molecular imprinting was carried out by using isoprocarb as template, methylacrylic acid (MAA) as functional monomer and ethylene glycol diglycidyl ether (EGDE) as crosslinker in the ethanol solution, and then the surface-molecular imprinted materials of isoprocarb (MIP-PMAA-MPS-SiO2) was obtained. The binding properties of MIP-PMAA-MPS-SiO2 for isoprocarb were studied with both static and dynamic methods. The experiment results showed that MIP-PMAA-MPS-SiO2 had specific recognition selectivity and excellent binding selectivity for the template molecule. In respect to the reference substance tsumacide and carbaryl, its selectivity coefficient for isoprocarb was 6.73 and 8.95, respectively. The relative selectivity coefficient was 4.43. After the Scatchard analysis, Qmax (the apparent maximum binding amount) values were calculated to be 229.6 and 116.7 mg g−1, respectively, and the dissociation constant (Kd) values were calculated to be 1428.6 and 476.2 mg L−1, respectively. Besides, the spiked recovery in rape samples experiment showed that imprinted material of MIP-PMAA-MPS-SiO2 can enrich and separate for trace amounts of isoprocarb, and it was also easy to be used repeatedly.

MIP-PMAA-MPS-SiO2 had specific recognition selectivity and excellent binding selectivity for the template molecule, the binding capacity of the MIP-PMAA-MPS-SiO2 to isoprocarb was 2–3 times that of NIP-PMAA-MPS-SiO2. In respect to the reference substance tsumacide and carbaryl, its selectivity coefficient for isoprocarb was 6.73 and 8.95, respectively. The relative selectivity coefficient was 4.43.Figure optionsDownload as PowerPoint slide