Abstract:

Molecularly imprinted polymer (MIP) using quercetin as template molecules, methacrylic acid as functional monomers, ethylene glycol dimethacrylate as crosslinking agent were prepared, and the binding sites of MIP were selectively modified with diazomethane.The effects of template molecule concentration, solvent and diazomethane usage on modification were discussed.The recognition capability and adsorption rate of MIP can be significantly enhanced by selective modification.Separation factor could be increased from 1.60 to 3.06 after modification when naringenin was chosen as competitive molecules, and the time needed for adsorption equilibrium could be reduced from 100 min to 60 min.Within a certain range, increasing template molecule concentration or diazomethane dosage, or adopting solvent which had weaker hydrogen bond action with template molecules could all improve the modification effect.The change of enthalpy, entropy and free energy of the different binding sites of initial MIP and modified MIP in adsorption process were estimated.From the point of view of thermodynamics, the modification effect and modification mechanism were further analyzed.