Camptothecin-imprinted polymer microspheres with rosin-based cross-linker for separation of camptothecin from Camptotheca acuminata fruit

In this work, camptothecin (CPT) molecularly imprinted polymer (MIP) microspheres were prepared via membrane emulsification-suspension polymerization using ethylene glycol maleic rosinate acrylate as a crosslinker, acrylic acid as a functional monomer, and CPT as a template molecule. The MIPs were characterized by scanning electron microscopy, laser granulometry, nitrogen sorption porosimetry, and thermogravimetric analysis. The results indicated that the MIPs had a regular spherical shape with porous surfaces and particle sizes mainly ranging from 3 to 5 μm. The surface areas of the MIPs and non-molecularly imprinted polymer (NIP) microspheres were 89.44 and 86.91 m2 g−1, respectively, and their respective average pore sizes were 11.42 and 10.84 nm. Furthermore, the MIPs and NIPs exhibited excellent thermal stabilities. The HPLC columns prepared with the MIPs and NIPs as the chromatographic stationary phase showed good fluidity. The effect of the MIP column on CPT was evaluated with HPLC, and the selectivity and separation performance of the MIP and NIP columns for CPT and 10-hydroxycamptothecin were evaluated. The chromatographic thermodynamics and separation mechanism were also studied. Finally, the MIP column was successfully applied to the separation and purification of CPT from an extract of Camptotheca acuminata fruit, and the reusability of the MIP column was also investigated.