Characterization and Evaluation of Binding Properties of Salvianolic Acid a Imprinted Polymers Prepared by Precipitation Polymerization

Abstract

Molecularly imprinted polymers (MIPs) were synthesized by precipitation polymerization using salvianolic acid A (Sal A), acrylamide (AA), ethylene glycol dimethacrylate (EGDMA) and acetonitrile as template molecule, functional monomer, cross-linker and solvent, respectively. The morphology of the obtained polymers was characterized by scanning electron microscopy (SEM). The effect of different polymerization conditions (solvent volume, solvent and template amount) on the size and shape of particles was investigated. The binding properties of the imprinted polymers were evaluated through the equilibrium rebinding experiments. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymers with equilibrium dissociation constants of 0.33 μmol·mL-1and 0.07 μmol·mL-1, respectively. Besides Sal A, two structurally related compounds, protocatechuic aldehyde (Pra) and salvianolic acid B (Sal B), were employed for molecular selectivity tests. The results indicated that the imprinted polymers exhibited good selectivity and specificity toward Sal A.