Bioactive fusion: The evolution of metal-organic framework/keratin composites in unveiling the biomedical...

Metal-organic frameworks (MOFs), with their high porosity, tunable architectures, and multifunctionality, have become a major area of research in the biomedical sciences. Keratin, a natural biopolymer rich in sulfur-containing amino acids, exhibits mechanical stability, intrinsic bioactivity, and excellent biocompatibility. The integration of MOFs with keratin leads to hybrid materials that combine the structural tunability of MOFs with the biological functionality of keratin, offering significant potential for biomedical and analytical applications. This review systematically analyzes the design principles, structural characteristics, and synthesis strategies, including in situ and ex situ approaches, employed in the fabrication of MOF/keratin composites. Key physicochemical properties such as surface chemistry, porosity, stability, and biodegradability in relation to their influence on biological performance are discussed. The applications of these composites in cancer therapy, regenerative medicine, and the analytical detection of bioactive compounds are summarized. Despite notable progress, challenges such as scalable fabrication, ensuring long-term stability, and comprehensive toxicity assessment remain barriers to clinical translation. Future research should focus on environmentally friendly and cost-effective synthesis methods, advanced multi-functional designs, and systematic in vivo evaluations to facilitate the transition of MOF/keratin composites from laboratory research to practical biomedical use.