| Calcium phosphate cement (CPC) is a bioceramic which can set in room temperature and be molded. After setting, it forms a certain porosity Hydroxyapatite (HA) or Brushite (DCPD) with low crystallinity, which has excellent biocompatibility and bioactivity. Therefore, CPC has been widely used in clinic for bone substitute and for carrier in drug delivery system to treat various skeletal diseases.In our previous study, we prepared and characterized CPC containing SMB (Salvia Miltiorrhiza Bunge). But the hydrolytic mechanism of the CPC with SMB or without SMB and the drug releasing in vitro have not been investigated. Furthermore, the mechanics strength of the CPC was too low to be applied in clinic. In this study, the aim are to investigate the setting behavior and hydrolytic mechanism, improve its mechanics strength and study the releasing beviour of SMB for CPC containing the SMB via in vitro releasing, finally develop the magnetic CPC primarily.The SMB injection was added in the synthesis of calcium hydrophosphate (DCP). Solid phases of the CPC were HA 8.5wt%, a-tricalcium phosphate (α-TCP) 58.0wt%, DCP 25.0wt% and CaCO3 8.5wt% according to literature. A solution (PBS) was mixture of Na2HPO4 and NaH2PO4. There were four different groups as blank (BCPC), containing SMB (SCPC), containing Fe3O4 (FCPC) and containing both of them (MCPC) in this study. PBS and distilled water were mixed with the solid phases to form a paste and fill the molded. Vicat needle was used to determine the initial and final setting times. X-ray diffraction was used to characterize the phase composition of the solid phases, CPC paste in setting process and hardened CPC. The CPC morphology in typicaly setting process was observed by scanning electronic microscope (SEM). In order to investigate the mechanics strength of the CPC, an orthogonal array, considering content and particle size of Fe3O4, L/S (liquid/solid) ratio, concentration of the liquid and incubated humidity of CPC, was...
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