Aloe-Emodin/Carbon Nanoparticle Hybrid Gels with Light-Induced and Long-Term Antibacterial Activity

Development of effective antimicrobial wound dressings has drawn wide attention in the wound care market. Here, we synthesized a natural antibiotic (aloe-emodin, AE) and a carbon nanoparticle coembedded polymer hybrid hydrogel as a novel wound dressing in the fight against potent skin infections. We systematically evaluated the properties of the obtained hydrogels, including physico-chemical characteristics, photothermal conversion efficiency, reactive oxygen species (ROS) generation, AE-released profile, antibacterial activity, and wound-healing capability. The hybrid gels can initially reduce the number of bacteria in a short time through the near-infrared-light (NIR) triggered photothermal/ROS route and continuously kill the remaining live cells by releasing AE from gels after turning off the NIR source with a long-term antibacterial effect. These two antibacterial mechanisms that complement each other lead to excellent antibacterial performance toward various bacterial strains including multidrug-resistant bacteria. Moreover, in vivo Staphylcoccus aureus-infected animal experiments indicate that the hybrid gels upon NIR irradiation have a striking ability toward wound infection. These studies demonstrate that the AE and carbon nanoparticle coembedded hybrid polymer hydrogels with NIR exposure may have applications in wound combined care for bacterial infections.