Deep Red-Light-Mediated Nitric Oxide and Photodynamic Synergistic Antibacterial Therapy for the Treatment of Drug-Resistant Bacterial Infections.

Infections caused by persistent, drug-resistant bacteria pose significant challenges in inflammation treatment, often leading to severe morbidity and mortality. Herein, the photosensitizer rhodamine derivatives are selected as the light-trapping dye and the electron-rich substituent N-nitrosoaminophen as the nitric oxide (NO)-releasing component to develop a multifunctional (deep) red-light activatable NO photocage/photodynamic prodrug for efficient treatment of wounds and diabetic foot infections. The prodrug, RhB-NO-2 integrates antimicrobial photodynamic therapy (aPDT), NO sterilization, and NO-mediated anti-inflammatory properties within a small organic molecule and is capable of releasing NO and generating Reactive oxygen species (ROS) when exposed to (deep) red laser (660 nm).