Injectable natural hydrogel-loaded Ta4C3 quantum dots self-assembled with Phillyrin-mediated NIR-II anti-infection for acute sinusitis

Acute sinusitis, common across populations, worsens seasonally due to pollution and improper medication, increasing the risk of chronic disease and impairing quality of life. To improve treatment and limit antimicrobial resistance in acute sinusitis, we developed a natural injectable QACS/SA@Py@Ta 4 C 3 hydrogel. It integrates the traditional Chinese medicine phillyrin with Ta 4 C 3 quantum dots and natural polymers—quaternary chitosan and sodium alginate. The hydrogel is designed for NIR II–mediated treatment of acute sinusitis via combined photothermal and photodynamic therapy. It exhibited a photothermal conversion efficiency of 22.6% and generated transient ROS, as demonstrated in vitro. Bacteriostatic experiments revealed that the hydrogel inhibited S. aureus with an efficiency of 99.7%. Furthermore, cell studies showed that the hydrogel was minimally cytotoxic, modulated macrophage cytokine expression, and displayed anti-inflammatory and antioxidant activities. Finally, in a rabbit sinusitis model, hydrogel implantation at the treatment site significantly reduced bacterial burden and decreased inflammation after NIR II laser treatment, demonstrating promising therapeutic potential.