No abstract

The purpose of this paper was to investigate the effect of various Chinese medicine adding methods on their contents in calcium phosphate (CaP) and the crystal structure of the CaP comparatively. In the present study, CaP was synthesized by the wet chemistry method, in which starting reagent grades calcium nitrate and diammonium phosphate were used as the molar ratio Ca/P=1.5. Chinese medicine parenteral solution, Salvia Miltirrhiza Bunge (SMB), was added into the Ca2+ and PO43- reactive solutions before, during or after synthesis process. CaP was synthesized without adding SMB as the control. UV-VIS spectrophotometer was used to measure the supernatant absorbency. Zeta potential was used to characterize the various CaP slurries. Thermogravimetry, X-ray diffraction and transmission electron microscope were used to characterize the various powders, respectively. The presented results showed that adding SMB during the reaction can obtain the maximal medicine content among the four different adding methods. There was a slight effect on the crystal structure of CaP by adding SMB.

In this study, biodegradable poly-lactic-acid (PLA) microspheres encapsulated with Salvia Miltiorrhiza Bunge (SMB), ranged from 100µm to 300µm, were prepared by a solvent evaporation method. Those PLA microspheres mixed with CPC powder, at a mass fraction of 0.2 to 0.8, to yield a self-emerged porous CPC. The surface morphology of PLA microspheres and CPC were observed by optical microscopy and scanning electron microscopy (SEM), respectively. The function groups of PLA microspheres and the phase composition of CPC were analyzed by Fourier transform infrared spectrometer (FTIR) and X-ray diffraction (XRD) , respectively. A preliminary study of drug release was performed by immersing PLA microspheres and CPC into simulated body fluid (SBF) for a various interval points. And the concentrations of SMB in SBF were measured by UV-VIS spectroscopy. The present results showed that the self-emerged porous CPC containing Chinese medicine could be prepared by adding biodegradable PLA microspheres. PLA microspheres can promote the CPC aqueous reaction to form final product, hydroxyapatite (HA).

The purpose of this study was to investigate the in vitro degradation and release behaviors of calcium phosphate powders (Ca/P) containing Chinese Medicine for bone graft. Two kinds of Ca/P powders, one with the Chinese Medicine, Salvia Miltiorrhiza Bunge (SMB) and the other with Polyacrylic Acid (PAA) and SMB, were soaked in simulated body fluid (SBF) for up to 150h. The in vitro release of SMB was measured by UV-VIS spectroscopy. The Ca2+ concentrations and pH of SBF soaked Ca/P powders were measured by AAS and pH meter. TA and XRD were employed to analyze various Ca/P powders before and after soaked in SBF, respectively. The results demonstrated that a faster SMB release occurred during the first 24 hours, while a slow release was sustained up to150h. Furthermore, the released of SMB in Ca/P-PAA-SMB was faster than that of Ca/P-SMB. It was concluded that a controllable release of Chinese Medicine from Calcium phosphate may be carried out by the addition of suitable surfactant. Accordingly, calcium ions were released into SBF, which was benefit for bone tissue repairing and reconstructing. Additionally, the TA results showed that there was 1.66% SMB released from Ca/P-SMB-PAA powders. XRD confirmed that various Ca/P powders possessed poorer crystallinity and smaller grain size.