Dopamine-triggered one-step functionalization of hollow silica nanospheres for simultaneous lubrication and drug release

Osteoarthritis (OA) has been regarded as a lubrication deficiency related joint disease. Combination of both joint lubrication and drug intervention may provide a promising nonsurgical strategy for treatment of OA. Developing novel and simple approaches to fabricate superlubricating nanoparticles with drug release property is highly required. Herein, dopamine triggered one-step polymerization method was employed to fabricate polydopamine/poly(3-sulfopropyl methacrylate potassium salt) (PDA—PSPMA) conjugate coating on hollow silica (h-SiO 2 ) nanosphere surfaces to engineer functional nanoparticles (h-SiO 2 /PDA—PSPMA). The as-prepared h-SiO 2 /PDA—PSPMA exhibits excellent aqueous lubrication performance on biomaterial substrates as well as natural bovine articular cartilage based on hydration effect of negatively charged PDA—PSPMA coating and “rolling” effect of h-SiO 2 nanospheres. In vitro drug loading-release experiments demonstrate that PDA—PSPMA coating functionalized h-SiO 2 nanospheres show high drug-loading and sustained-release capability of an anti-inflammatory drug, diclofenac sodium (DS). Such h-SiO 2 /PDA—PSPMA nanospheres can be potentially used as a synergistic therapy agent for OA treatment combining by simultaneous joint lubrication and drug release.