Silk fibroin-photothermal agent composites: Innovations in biomedicine

Silk fibroin (SF), as a naturally occurring polymer, has emerged as a highly appealing biomaterial within the field of biomedicine, attributed to its hierarchical architecture, exceptional mechanical characteristics, and adjustable biodegradability. Photothermal agents (PTAs) are distinguished by their high photothermal conversion efficiency, favorable biocompatibility, and ability to penetrate deeply into tissues. The integration of PTAs with SF presents significant potential for advanced biomedical applications. This review explores silk fibroin-photothermal agent composites (SF-PTAs), highlighting their photothermal conversion abilities, environmental responsiveness, and multifunctionality. SF-PTAs show promise in tumor therapy, wound healing, tissue engineering, and biosensing. In oncology, near-infrared-induced hyperthermia aids tumor ablation, while drug release, immune activation, and tumor microenvironment modulation help prevent metastasis and boost immunity. For wound healing, SF-PTAs enhance tissue regeneration through antibacterial effects, inflammation control, and angiogenesis, proving effective for diabetic ulcers and burns. In neural engineering, they improve electrical signaling and axonal growth, and they also enable sensitive biosensing. However, challenges remain in photothermal stability, targeting precision, and scalable production. Future research should aim to develop silk-regulated NIR-II biomaterials, smart targeting systems, and multimodal strategies to improve clinical applications in precision and regenerative medicine.