Abstract:

The novel self-setting calcium phosphate microspheres were prepared by the employment of a reversed emulsion method. The diameter of the microspheres distributed from 100 μm to 1000 μm with a median diameter between 388~605μm, with a porosity between 43.4%~66.7%. The processing parameters for preparation of the microspheres were optimized to be: an agitating speed of 200r/min, a gelatin concentration of 8%w/v, an oil to water ratio of 5:1, and a liquid to powder ratio of 2.0. The angle of repose of the microspheres was measured to be 28.4°~31.6°, indicating good flowability. The compressive test showed that the microspheres were non-brittle, which is in favor of clinical applications. The compressive performance of the microspheres was significantly improved after full hydration at 37°C and 97% humidity. Anti-disintegration test revealed the microspheres was endurable in simulated physiological conditions and MTT test indicated the microspheres were biocompatible. The self-setting calcium phosphate microspheres were a potential candidate for bone defect filling at non-load-bearing sites and drug carrier.

Key words: self-setting calcium phosphate cement, microsphere, reversed emulsion method, hydroxyapatite, anti-disintegration