Self-Oxygenating Nano-Thermosensitive Hydrogel System Integrated with Photothermal/Photodynamic Therapy for...

The treatment of multidrug-resistant (MDR) infections remains a major challenge faced by humans. Effective phototherapy, such as photothermal and photodynamic therapies, can inhibit drug-resistant bacteria and is considered an innovative treatment approach that can replace antibiotics. In this study, molybdenum disulfide (MoS₂) nanoflowers, photosensitizer chlorin-e6 (Ce6), autogenic oxygen nanocalcium oxide (CaO₂), and MOF material (ZIF-8) were used to construct MoS₂-Ce6-CaO₂@ZIF-8 (MCC@ZIF-8), an autogenic oxygen multifunctional nanosystem. This system exhibited photothermal and photodynamic antibacterial activities in the active near-infrared (808 nm) and visible (660 nm) regions of the spectrum. The experimental results indicated that the nanosystem was hexahedral, its zeta potential was +38 ± 1.1 mV, particle size was approximately 310 nm, and photothermal conversion efficiency was 47%. In the experiment, this nanosystem showed >95% antibacterial effect against MDR Escherichia coli and Staphylococcus aureus. Furthermore, it could inhibit the expression of bacterial base excision repair, tyrosine metabolism, glutathione metabolism, and other genes. The hydrogel system MCC@ZIF-8@BBR/CS/β-GP (MCC@ZIF-8@BCβ) further promoted wound healing in the infected mice. These findings confirm the significant antibacterial effect of the autogenic oxygen multifunctional nanocomposite and lay the foundation for the practical application of this nanosystem in clinical practice.