A new molecularly imprinted polymer prepared by surface imprinting technique for selective adsorption towards kaempferol

A new molecularly imprinted polymer (KAE-MPS/SiO₂) with high performance for recognizing kaempferol (KAE) was prepared by adopting the surface molecular imprinting technique with silica nanoparticles modified with 3-methacryloxypropyltrimethoxysilane (MPS) as a carrier material, 2-vinylpridine as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. The static adsorption experiments indicated that KAE-MPS/SiO₂ had significantly higher adsorption capacity for KAE than its non-imprinted polymers. Scatchard analysis revealed that two classes of binding sites were formed in KAE-MPS/SiO₂ with dissociation constants of 0.26 and 2.34 μmol/mL, and the maximum apparent binding capacity was 3.33 and 16.16 μmol/g, respectively. The selectivity coefficients of KAE-MPS/SiO₂ for KAE in relation to competition species myricetin and chlorogenic acid were 2.51 and 4.24, respectively, which suggested that KAE-MPS/SiO₂ had high recognition selectivity and binding affinity for the template KAE. Dynamic binding study showed that the KAE-MPS/SiO₂ had good site accessibility and mass transport for KAE. The KAE-MPS/SiO₂ can be reused many times without decreasing their adsorption capacities significantly.