Synthesis of magnetic bifunctional monomer molecularly imprinted polymers for highly selective separation of paclitaxel from Taxus cuspidata

Paclitaxel (PTX), an active anticancer compound derived from Taxus cuspidata, possesses considerable economic value. Given the abundance of structural analogs, the selective separation of PTX from T. cuspidata presents a formidable challenge. In this study, the bifunctional monomers magnetic molecular imprinted polymers (MMIPs) with multiple active sites were synthesized using Fe3O4 as the magnetic carrier, PTX as the template, 4-vinylpyridine (4-VP) and methacrylic acid (MAA) as the first-stage and the second-stage pre-assembly functional monomer, respectively. The results indicated that MMIPs exhibited excellent magnetic recovery capability and high adsorption capacity for PTX. Furthermore, the adsorption behaviors were more consistent with Langmuir isotherm model and pseudo-second-order kinetic model. The MMIPs possessed significantly higher selectivity for PTX than five structural analogs (Docetaxel, Baccatin III, 10-Deacetylbaccatin III, and Glucose) and recyclability for up to six cycles. Additionally, the adsorption mechanism analysis indicated that the excellent performance of MMIPs primarily arises from the multiple active binding sites involving hydrogen bonding and pi-pi stacking. Finally, MMIPs were used for PTX recognition and separation in T. cuspidata extracts. This study provides an efficient method and valuable theoretical basis for the highly selective separation of PTX from T. cuspidata.