Abstract: The surface-initiated graft-polymerization of glycidyl methacrylate(GMA) on micron-sized silica gel particles was first conducted with a surface-initiating system of thiol group/azodiisobutyronitrile(AIBN) to obtain PGMA-grafted SiO2 particles. Sulfonate groups were bonded onto the side chains of PGMA by ring-opening reaction between the epoxy groups of PGMA and sodium 2,4-diaminobenzene sulfonate(SAS), resulting in the formation of SAS-PGMA/SiO2 particles. The interaction between SAS-PGMA/SiO2 and matrine was examined. Surface-imprinting of the matrine molecule was performed with glutaraldehyde as the crosslinking agent to yield the matrine molecule surface-imprinted material MIP-SASP/SiO2. The experiment results show that in the nearly neutral solution, there is strong host-guest interaction between the functional grafted particles SAS-PGMA/SiO2 and matrine. The surface-imprinted MIP-SASP/SiO2 particles, have specific recognition selectivity and excellent binding affinity for matrine. Relative to the cytosine control, the coefficient of recognition selectivity of the imprinted material MIP-SASP/SiO2 for matrine reaches 10.7.

Key words: poly(glycidyl methacrylate), silica gel, molecular surface-imprinting, matrine, molecular-recognition