Intelligent bacteria‐targeting ZIF‐8 composite for fluorescence imaging‐guided photodynamic therapy of drug‐resistant superbug infections and burn wound healing

Abstract

Infected burn wounds are characterized by persistent drug‐resistant bacterial infection coupled with an inflammatory response, impeding the wound‐healing process. In this study, an intelligent nanoparticle system (CCM+TTD@ZIF‐8 NPs) was prepared using curcumin (CCM), an aggregation‐induced emission luminogens (TTD), and ZIF‐8 for infection‐induced wound healing. The CCM+TTD@ZIF‐8 NPs showed multiple functions, including bacteria targeting, fluorescence imaging and pH response‐guided photodynamic therapy (PDT), and anti‐inflammatory. The positive charges of ZIF‐8 NPs allowed the targeting of drug‐resistant bacteria in infected wounds, thereby realizing fluorescence imaging of bacteria by emitting red fluorescence at the infected site upon blue light irradiation. The pH‐responsive characteristics of the CCM+TTD@ZIF‐8 NPs also enabled controllable CCM release onto the infected wound site, thereby promoting the specific accumulation of ROS at the infected site, with outstanding bactericidal efficacy against drug‐resistant Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) strains in vitro/in vivo. Additionally, due to the excellent bactericidal effect and anti‐inflammatory properties of CCM+TTD@ZIF‐8 NPs combined with blue light irradiation, the regeneration of epidermal tissue, angiogenesis, and collagen deposition was achieved, accelerating the healing process of infected burn wounds. Therefore, this CCM+TTD@ZIF‐8 NPs with multifunctional properties provides great potential for infected burn wound healing.

Harnessing the Potential of a Nitroreductase-Responsive Fluorescent Probe for the Diagnosis of Bacterial Keratitis

“…Fluorescence imaging has been extensively studied in the detection of bacterial infections due to its operational simplicity, high sensitivity, real-time imaging capability, and noninvasiveness. − However, there are only a limited number of fluorescent probes developed for in vivo diagnosis of bacterial keratitis. For instance, fluorescent silicon nanoparticles and boron-dipyrromethene (BODIPY) were modified with recognition elements such as vancomycin and boric acid to construct bacteria-targeted probes.…”