Injectable Violet Phosphorus-Based Hydrogel for Synergistic Photothermal/Photodynamic and Anti-Inflammatory Therapy of Acute Sinusitis

Traditional Chinese medicine (TCM) with minor side effects for treating acute sinusitis was developed by constructing an injectable multifunctional hydrogel (CS/SA@VP@SZ), which was self-assembled by sangzhi alkaloid (SZ) with violet phosphorus (VP) nanosheets for antibacterial and anti-inflammatory purposes and then compounded with chitosan (CS) and sodium alginate (SA). The hydrogel demonstrated significant synergistic photothermal and photodynamic therapeutic effects, exhibiting a photothermal conversion efficiency of 49.2%. Critical findings included a potent antibacterial inhibition rate of 99.1% against bacteria, excellent biocompatibility, and regulation of the secretion of macrophage-related inflammatory cytokines. In a rabbit sinusitis model, the hydrogel combined with 808 nm laser irradiation significantly suppressed bacterial proliferation, reduced inflammation, and alleviated mucosal tissue damage. This study not only provides a multifunctional hydrogel material for the treatment of acute sinusitis but also paves the way for the modern application of TCM.