Preparation of silica nanoparticles based multifunctional therapeutic systems via one-step mussel inspired modification

Silica nanoparticles (SiO2 NPs) have currently drawn great attention for various biomedical applications because of their outstanding physicochemical properties such as desirable biocompatibility, chemical inert and multifunctional potential. However, to achieve the optimal performance, surface modification of SiO2 NPs with other components is generally required. In this work, we reported a facile one-step biomimetic strategy for surface modification of SiO2 NPs with synthetic polymers. The hydrophilic polymers (poly(PEGMA-IA-DA)) were synthesized based on free radical polymerization of polyethylene glycol methyl ether methacrylate (PEGMA) and itaconic anhydride (IA). Then dopamine hydrochloride (DA) was reacted with the pendant IA of poly(PEGMA-IA-DA) by ring opening reaction. Taken advantage of the adhesion of DA, these synthetic polymers can effectively coat on SiO2 NPs in aqueous solution at room temperature and without using any toxic agents. On the other hand, therapeutic agents such as cisplatin (DDP) can be loaded on SiO2-poly(PEGMA-IA-DA) with high efficiency and showed controlled release kinetics because a large number of carboxyl groups were generated during the ring opening reaction. The results showed that SiO2-poly(PEGMA-IA-DA) displayed high water dispersibility, low cytotoxicity and controllable drug loading and release behavior, making them promising for multifunctional biomedical applications.