[A study of bone-like apatite formation on porous calcium phosphate ceramics in dynamic SBF]

This study aimed at investigating the influence of the flow rate of simulated body fluid (SBF) (2 ml/100 ml.min) of body fluid in skeletal muscle upon the formation of bone-like apatite on porous calcium phosphate ceramics. The in vitro immersion experiment in SBF flowing at normal physiological rate is referred to as dynamic SBF. The results showed that bone-like apatite could only formed in the pores of porous calcium phosphate when SBF flow at physiological rate (2 ml/100 ml.min) of body fluid in skeletal muscle. At the same time, bone-like apatite could form both in the pores and on the surface of the samples if the flowing physiological solution is 1.5 SBF. When the flowing speed of SBF is higher than normal physiological speed (10 ml/100 ml.min), no bone-like apatite could be detected both on the surface and in the pores of the materials. This result is in concordance with animal experiments. The dynamic SBF simulates the biological environment of bone-like apatite formation in body better than static SBF (SBF does not flow). This method is very useful for the research of the mechanism of bonelike apatite formation, which is the key step of bone growth on biomaterials, and can be used as an effective approach to investigate mechanism of the osteoinduction of calcium phosphate in nonosseous tissues in vivo.