Immunomodulatory hydrogel patches loaded with curcumin and tannic acid assembled nanoparticles for radiation dermatitis repair and radioprotection

•The curcumin@tannic acid nanoparticles exhibit high-efficiency antioxidant properties and immunomodulatory functions.•The high-water content characteristic of the gelatin methacryloyl hydrogel enables efficient absorption of low-energy X-rays.•The nanohybrid hydrogel patches display excellent efficacy in the radiation dermatitis model. Radiation dermatitis, as a major side effect of radiotherapy, is a form of skin injury linked to the production of reactive oxygen species (ROS). Development of functional patches with excellent ROS scavenging ability and biosafety is crucial for radioactive dermatitis repair. Herein, we present a nanohybrid hydrogel patch composed with natural-derived substances. The patch possesses dual functionalities of chemically scavenging ROS and physically absorbing radiation, thereby alleviating radiation damage. Curcumin@tannic acid (Cur@TA) nanoparticles are synthesized through spontaneous coordination of TA and iron ions (Fe3+), enabling the encapsulation of Cur. The nanoparticles are then loaded into gelatin methacryloyl (GelMA) hydrogel patches, which endow the hydrogel with tissue adhesion as well as photothermal properties. Simultaneously, the patch exhibits powerful ROS scavenging capability and promotes M2 polarization of macrophages. Additionally, the high-water content of the GelMA hydrogel enables physical absorption of low-energy X-rays, providing radiation shielding. Based on these characteristics, we have demonstrated the augmented therapeutic efficacy of the hydrogel patch loaded with Cur@TA nanoparticles in the mouse model of radiation dermatitis. Our findings introduce a novel therapeutic approach for radiation protection and treatment, with potential clinical applications.