Photoresponsive itaconate based bioadhesive reinforced with hydroxyapatite for potential bone repair application

Bone adhesives emerge as essential biomaterials in orthopedic and trauma surgery, particularly for the fixation of complex bone fractures. The design of bone adhesives that combine strong adhesion, biodegradability, mechanical reliability, and osteoconductivity has garnered increasing research interest. Inspired by the compositional similarity to natural bone, hydroxyapatite (HA) was selected as an ideal reinforcing filler. In this study, a fully bio-based, photocurable itaconate-based bioadhesive poly(1,3-propanediol-co-citrate-co-itaconate-co-1,12-dodecanedioate) incorporated with HA (PCIDHA) was developed. The influence of varying HA content on the physicochemical and mechanical properties of PCIDHA composites was systematically evaluated. HA incorporation improved the composite’s mechanical strength and adhesion performance, primarily through physical interactions between polymer chains and HA particles. In vitro biomineralization testing in simulated body fluid confirmed the formation of calcium phosphate layers on the composite surface, supporting its osteoconductive potential for bone regeneration. Furthermore, the composites exhibited non-cytotoxic behavior, indicating their suitability for biomedical applications. These results highlight the potential of PCIDHA as a photoresponsive, bioactive adhesive system for use in bone repair.