Objective: The overall objective of our study is to develop an Mg-substituted BCP (MCMP or Mg-BCP) as potential scaffolds for bone regeneration. The objective of the present study is to determine the effect of preparation methods on the toxicity of the calcium phosphates.
Method: Calcium deficient apatites (CDA) were prepared by hydrolysis methods. The CDA’s were filtered and washed using different volumes of double distilled water: group A, with 2L and group B with 6L. The CDAs were calcined at 950oC for 11h. The identification and compositions of the different CDAs before and after calcinations were confirmed using x-ray diffraction, FTIR and inductive coupled plasma. A colorimetric cell viability assay (MTT) was performed using a mouse osteoblastic cell line (MC3T3-E1) to determine the toxicity of the CDA preparations.
Result: β-TCMP or BCMP were obtained after calcining Mg-substituted CDAs, depending on the Mg/Ca molar ratio of the CDA. β-TCP was obtained after calcining Mg-free CDA. The MTT assay indicated a reduction in cell viability for β-TCP and β-TCMP obtained from CDAs from group A indicating toxicity for these compounds. β-TCP, β-TCMP and BCMP obtained from CDAs from group B promoted cell proliferation indicating non-toxicity.
Conclusion: Calcium phosphate materials are generally considered biocompatible. However, the results from this study demonstrated that processing methods (e.g., washing) of the calcium phosphate preparations can affect the biocompatibility (toxicity) of the calcined products.