Phase-Transited Lysozyme as a Universal Route to Bioactive Hydroxyapatite Crystalline Film

A key factor for successful design of bioactive complex, organic-inorganic hybrid biomaterials is the facilitation and control of adhesion at interfaces, as many current synthetic biomaterials are inert, lacking interfacial bio-activity. In this regard, the development of a simple, unified way to bio-functionalize diverse organic and inorganic materials toward biominer-alization remains a critical challenge. In this report, a universal biomimetic mineralization route that can be applied to virtually any type and morphology of scaffold materials is provided to induce nucleation and growth of hydroxyapatite (HAp) crystals based on phase-transited lysozyme (PTL) coating. Surface-anchored abundant functional groups in the PTL enrich the interface with strongly bonded calcium ions, facilitating the formation of HAp crystals in simulated body fluid with the morphology and alignment being similar to that observed in natural HAp in mineralized tissues. By the adhesion of amyloid contained in the PTL, such protein assembly could readily integrate HAp on ceramics, metals, semiconductors, and synthetic polymers irrespective of their size and morphology, with robust bonding stability and corresponding ultralow wear extent under normal bone pressure. This strategy successfully improves the in vivo osteoconductivity of Ti-based implant, underpinning the expectation for such biomaterial in future bio-interface and tissue engineering.