Molecularly Imprinted Polymer Based on Carboxymethylcellulose/Graphene Oxide Composites for Selective Adsorption of Hydroxycamptothecin

Molecularly imprinted polymers based on carboxymethylcellulose/graphene oxide composites (CMC/GO@MIPs) were prepared using surface molecular imprinting technology for the adsorption of hydroxycamptothecin (HCPT). Using molecular simulations, methacrylic acid was selected as a suitable monomer via a preliminary green scheme. The structure and adsorption properties of CMC/GO@MIPs were investigated through various characterization methods and adsorption experiments. The adsorption mechanism was examined using an adsorption model. The Langmuir isotherm model and pseudo-second-order kinetic model matched well with the adsorption results, with a maximum adsorption capacity of 62.92 mg/g. Adsorption equilibrium was achieved within 30 min. Further, CMC/GO@MIPs exhibited excellent selectivity for HCPT (imprinting factor of 2.60) and good recyclability; the adsorption capacity decreased by only 10.50% after seven adsorption–desorption cycles. The purity of HCPT was 50.94% after separation in the actual sample. CMC/GO@MIPs prepared in this study are simple and convenient to use and display high specificity, extraction efficiency, stability, and reusability for the separation and enrichment of HCPT. This study provides a method for the separation and purification of HCPT in Camptotheca acuminata Decne and is an important reference for the separation, enrichment, and purification of natural components present in complex plant matrices.