In vitro bioactivity and degradability of injectable poly(propylene fumarate)/beta-tricalcium phosphate bone cement / 中国组织工程研究

ABSTRACT

BACKGROUND:Poly(propylene fumarate) (PPF) can crosslink at room temperature, andβ-tricalcium phosphate (β-TCP) has good biocompatibility, but PPF/β-TCP composite bone cement has not yet been systematical y studied. OBJECTIVE:To prepare PPF/β-TCP composite bone cement and to explore its in vitro bioactivity and degradability. METHODS:β-TCP and PPF were respectively synthesized by liquid-phase precipitation and a two-step method, and PPF/β-TCP composite bone cement was prepared through mixing PPF withβ-TCP. The in vitro bioactivity of PPF/β-TCP was compared with the commercial poly(methyl methacrylate) (PMMA) through the ability of forming hydroxyapatite after immersed in simulated body fluid for 7 days. The in vitro degradability of PPF/β-TCP was studied via investigating the transformation of pH values, water uptake and mass loss, compressive strength and morphology at each time point. RESULTS AND CONCLUSION:There were hydroxyapatites formed on the PPF/β-TCP material, but none on the commercial PMMA material. The pH values of the PPF/β-TCP were stable in PBS for 63 days, indicating its degradation is moderate;the mass loss was up to 13.5%after 84 days. Scanning electron microscope displayed the degraded PPF/β-TCP surface, and its compressive strength was decreased gradual y, which good for the integrity and sustainability of mechanical properties during degradation. These results suggest that PPF/β-TCP bone cement holds mineralization and degradability in vitro.