title: Apatite formation on the surface of wollastonite/tricalcium phosphate composite immersed in simulated body fluid.
abstract: Wollastonite/tricalcium phosphate composites were prepared and immersed in SBF for various periods to investigate the apatite-formation mechanism on their surfaces. Surface morphologies and composition before and after immersion were analyzed by SEM and EDS technologies. The concentration changes of calcium, silicon, and phosphorus in SBF due to the immersion of the samples were measured with inductively coupled plasma atomic emission spectroscopy, and the corresponding pH values in SBF were recorded. XRD and IR were used to examine the changes in crystalline phases and functional groups. It was found that, after immersion for 1 day, the samples were covered by pom-pom-like apatite granules, resulting from the dissolution of wollastonite and the simultaneous transformation of TCP. This quickly led to the subsequent precipitation of another apatite layer, which covered the earlier-formed surface completely. These results indicate that the wollastonite/tricalcium phosphate composite is a potential biomaterial candidate because of its high bioactivity and in situ porous structure.
authors.affiliation: Institute of Materials Sciences and Engineering, Ocean University of China, Qingdao 266003, People's Republic of China. hx929@hotmail.com
authors.forename: Xiang
authors.initials: X
authors.lastname: Huang
authors.forename: Dongliang
authors.initials: D
authors.lastname: Jiang
authors.forename: Shouhong
authors.initials: S
authors.lastname: Tan
mesh_terms: D001031:Apatites / Q000737:chemistry*; D001826:Body Fluids / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D006863:Hydrogen-Ion Concentration; D007101:Immersion; D008855:Microscopy, Electron, Scanning; D017640:Silicates / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D017610:Calcium Compounds; D002130:Calcium Phosphates; D017640:Silicates; C018392:tricalcium phosphate; C031293:calcium silicate