Kaempferol molecularly imprinted polymers: preparation, characterization and application to the separation of kaempferol from ginkgo leaves

In this work, kaempferol molecularly imprinted polymers (MIPs) were screened in detail and were applied to the separation of kaempferol from real complex systems. Kaempferol-MIPs with high affinity and selectivity for kaempferol could be prepared successfully by using kaempferol as the template molecule, 4-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate or divinylbenzene as the crosslinker, acetone or acetonitrile as the solvent. Scanning electron microscopy observation and Brunauer–Emmett–Teller measurement showed that the prepared MIPs had a heterogeneous pore structure and large specific surface area. Static and dynamic adsorption experiments and solid-phase extraction application were performed to evaluate the performance of the prepared MIPs. Only the MIPs with both higher distribution coefficient and higher imprinting factor in the dynamic experiments had better ability to retain kaempferol. Using the screened MIPs as solid-phase extraction sorbents, kaempferol and quercetin were extracted directly from the crude ginkgo leaves hydrolysate with high recovery and purity. Control experiments also showed that the screened MIPs were superior to commercially available adsorbents in terms of the separation of kaempferol from crude extracts. © 2023 Society of Industrial Chemistry.