Surface structural biomimetics and the osteoinduction of calcium phosphate biomaterials.

From the point of view of materials, many natural tissues could be regarded as materials with certain nanostructure thus have special biological function. These natural nanostructures are generally formed under soft biological condition and show excellent biocompatibility and biological functions. To get materials with certain biological function, it is expectable to construct some nanostructure by mimicking the natural soft process. In this study, the porous biphasic calcium phosphate (BCP) ceramic was used to study the relationship of surface micro/nano structure and the biological function of osteoinductivity. Surface structural biomimetic was achieved by a soft technology of surface treating with simulated body fluid (SBF) or SBF containing protein molecules (BSA-SBF). The biological function of osteoinduction was tested by studying the bone formation in the samples implanted in dog nonosseous sites. The results showed that by the soft biomimetic process, the surface was re-constructed and the surface characteristics varied with the biomimetic process. The biological function of osteoinductivity depended on the surface characteristics. The present of protein molecules was likely to construct a surface structure which was different from that without the protein molecules and showed higher osteoinductivity. The study gave the evidence of material surface structural biomimetic to promote biological function as well as the possibility of the application of soft-nano technology to construct a micro/nano structural surface/interface of biomaterials with certain biological function.