Single NIR laser-activated synergistic low-temperature photothermal therapy and self-oxygenated photodynamic therapy nano-platforms for bacteria infection

The emergence and spread of drug-resistant bacterias with new resistance mechanisms leads to antimicrobial resistance and continues to threaten our ability to treat common infections. Herein, a nano-platform (PB@MnO2@MB@HA) was provided to bring significant bacterial inhibition via win-win photo-combination therapy strategy mediated by a single wavelength. More importantly, with well photothermal conversion efficiency, the nano-platform enables effective low temperature photothermal therapy (below 42 degree celsius), where the heat generated is advantageous for the advancement of photodynamic therapy. Moreover, the addition of manganese dioxide promotes the supply of oxygen and addresses the limitations of low-oxygen environments on photodynamic therapy, further enhancing its therapeutic effect, which in turn compensates for the efficacy of low temperature photothermal. The nano-platform can effectively inhibit the growth of Gram-negative bacteria with an inhibition rate of 99%. In summary, the combined therapy of low-temperature photothermal therapy and selfoxygenated photodynamic therapy synergistically improves the efficacy of bacteria treatment while reducing the side effects associated with two therapy alone. The photo-combination nano-platform triggered by single wavelength near infrared irradiation has significant clinical application potential in overcoming the limitations of monotherapy for bacterial infection.