Dual antibacterial behavior of a curcumin–upconversion photodynamic nanosystem for efficient eradication of drug-resistant bacteria in a deep joint infection

Abstract

A periprosthetic joint infection (PJI) with methicillin-resistant Staphylococcus aureus (MRSA) is a catastrophic deep joint infection for patients who have had joint replacement surgery. To efficiently eradicate the MRSA, curcumin–upconversion nanoparticles (curcumin–UCNPs) were synthesized by binding the curcumin onto UCNPs, which could produce singlet oxygen under near infrared (NIR) irradiation. Dual antibacterial behavior induced by the curcumin–UCNP itself and induced by photodynamic therapy were demonstrated. Nearly 100% MRSA was eradicated using curcumin–UCNPs under the NIR irradiation because of the dual antibacterial behavior in vitro. Furthermore, a MRSA-induced PJI model was constructed using Sprague Dawley rats. The NIR could penetrate the rats’ knee joint tissue well and activated the curcumin–UCNPs to perform photodynamic therapy, which exhibited a good antibacterial effect in the deep joint tissue (1 cm) and about 80% of MRSA was eradicated in vivo. Blood tests and histopathological examinations revealed that the inflammation was also significantly relieved because of the eradication of MRSA in the curcumin–UCNPs-NIR group. Compared with traditional treatments, this research may provide a new therapy for PJI.