In vitro transformation of OCP into carbonated HA under physiological conditions

The effect of mineral coating morphology on mesenchymal stem cell attachment and expansion

“…It has been reported that several precursor phases such as dicalcium phosphate dihydrate (DCPD), and octacalcium phosphate (OCP) can convert to hydroxyapatite (HA) in physiological conditions, as HA phase is the most stable mineral phase in physiological conditions. 35 Studies have indicated that OCP transformation to carbonated apatite resulted from an interfacial dissolution-reprecipitation mechanism in the presence of Ca 2+ , PO 4 3− , and CO 3 2− ions in MEM cell culture medium. For example, Barrère et al demonstrated that OCP coatings on Ti surfaces transformed to a carbonated apatite phase after a 2 week incubation in MEM medium.…”

In situ time-resolved X-ray diffraction study of octacalcium phosphate transformations under physiological conditions

“…Some literature references [12][13][14][15][16][17] reported the results of OCP transformation into HA; however, detailed in situ investigation of the processes taking place upon this transformation is lacking, this, in part, due to the limitations of existing experimental methods. The advantage of the applied energy dispersive X-ray diffraction (EDXRD) technique, compared to its conventional angular dispersive counterpart (ADXRD), is that it allows rapid collection of diffraction patterns, and therefore, the phase transformations occurring in the system can be easily monitored in situ.…”

Bioactive Microarc Oxidized TiO2-based Coatings for Biomedical Implication

“…Lu et al [Lu et al, 2007] found that amorphous CaP coatings were formed on the surfaces by immersing the nitric acid treated Ti specimens in SBF, while OCP coatings were formed in the supersaturated calcium phosphate solution after 3 days of immersion. And, OCP could further transfer into carbonated-HA in SBF [Horváthová et al, 2008]. Based on the this investigation, compared to HA and carbonated-HA, the formation of OCP is highly dependent on f(θ), σ and local ions concentration near substrate surfaces.…”

“…In fact, the formation of apatite on the surface of substrates is a very complex process, since various factors have effect on the apatite nucleation and growth such as supersaturation or the solution compositions, interface energy and contacting angle of apatites and substrates, etc.. The precipitation of apatite from SBF or the supersaturated calcium phosphate solution (differing from SBF in composition containing higher Ca and P concentrations) has been widely investigated in the past [Feng et al, 1999;Li et al, 2002;Barrère et al, 1999;Lu et al, 2004;Lu et al, 2007;Horváthová et al, 2008;Xie et al, 2006]. Experimental observation indicated that some important characteristics of the initial behaviors of apatite formation.…”