Type-I Photosensitizer-Triggered Controllable Carbon Monoxide Release for Effective Treatment of Staph Skin Infection.

Abstract

<i>Staphylococcus aureus</i> (<i>S. aureus</i>) infection is a major infectious skin disease that is highly resistant to conventional antibiotic treatment and host immune defense, leading to recurrence and exacerbation of bacterial infection. Herein, we developed a photoresponsive carbon monoxide (CO)-releasing nanocomposite by integrating anion-π⁺ type-I photosensitizer (<b>OMeTBP</b>) and organometallic complex (<b>FeCO</b>) for the treatment of planktonic <i>S. aureus</i> and biofilm-associated infections. After optimizing the molar ratio of <b>FeCO</b> and <b>OMeTBP</b>, the prepared nanoparticles, <b>OMeTBP@FeCONPs</b>, not only ensured sufficient loading of CO donors and efficient CO generation but also showed negligible free ROS leakage under light irradiation, which helped to avoid tissue damage caused by excessive ROS. Both <i>in vitro</i> and <i>in vivo</i> results demonstrated that <b>OMeTBP@FeCONPs</b> could effectively inhibit <i>S. aureus</i> methicillin-resistant <i>S. aureus</i> (<i>MRSA</i>), and bacterial biofilm. Our design has the potential to overcome the resistance of conventional antibiotic treatment and provide a more effective option for bacterial infections.