Dual-responsive dithio-polydopamine coated porous CeO2 nanorods for targeted and synergistic drug delivery

Objective The aim was to produce the first report of assembling degradable stimuli-responsive dithio-polydopamine coating with a cancer target unit for synergistic and targeted drug delivery.Methods A multifunctional drug delivery system was constructed by coating a dual-responsive dithio-polydopamine (PDS) on porous CeO2 nanorods and subsequent conjugation of lactose derivative, where the PDS was formed by self-polymerization of dithio-dopamine (DOPASS).Results The multifunctional drug delivery system displayed excellent cancer targeted ability resulting from the conjugation of lactose derivative, which could specifically recognize the overexpressed asialoglycoprotein receptors on the surface of HepG2 cells. It also showed a dual-responsive property of glutathione and pH, achieving controllable drug release from the cleavage of disulfide bond and subsequent degradation of PDS in cancer cells. Moreover, the degradation of PDS led to the exposure of CeO2 nanorods, which has a synergistic anticancer effect due to its cytotoxicity to cancer cells.Conclusion This work presents a good example of a rational design towards synergistic and targeted DDS for cancer chemotherapies.