钛种植体表面磷酸化及其对骨髓间充质细胞的成骨诱导实验研究

Phosphorylation of titanium surface and its induction of osteogenic differentiation of bone marrow stromal cells

目的:观察磷酸化处理的钛基材表面对骨髓间充质细胞(BMSCs)增殖和分化的影响。方法:先用85%的磷酸然后用8.5%磷酸对钛基材表面进行酸蚀处理,在模拟体液内进行体外仿生矿化实验。取生长旺盛的大鼠第3代BMSCs分别接种于矿化钛片、磷酸化钛片、酸蚀钛片及光滑钛片表面,扫描电镜观察细胞生长的形貌,MTT和ALP活性实验检测细胞的增殖和分化能力。结果:钛基材磷酸化处理后形成粗糙、多孔的表面,再经过高温、高压处理,生成与钛基材表面化学键合的Ti(H2PO)3晶体层,此层富含-OH及-PO43-离子,具备生物矿化诱导功能;磷酸化钛材表面能显著促进BMSCs的增值和分化。结论:简捷的物理、化学方法可以实现对钛种植体表面的磷酸化改性,磷酸化钛种植体表面可促进BMSCs成骨向分化能力。

Objective： To modify the titanium surface by phosphorylation and to study its induction of osteogenic differentiation of bone marrow stromal cells（BMSCs） Methods： The surface of pure titanium was treated by 85% orthophosphoric acid （H3 PO4 ） and followed by 8.5% of H3PO4, then the specimens were soaked in the simulated body fluid （SBF）. Rat BMSCs of passage 3 were cul- tured on the titanium surface. The proliferation and differentiation of BMSCs were examined by MTT assay and ALP test. Results： The modified titanium surface characterized by a complex construction, which consisted of a mesh-like matrix （a micro-roughened surface） with titanium dihydrogen orthophosphate Ti（ H2PO4 ）3 crystal containing -OH and -PO_4^3-. BMSCs cultured on the modified surface revealed a well spread morphology. Cell viability and ALP activity of BMSCs on these altered surfaces were found to be greater than those on the controls. Conclusion： Treatment of titanium by acid etching with orthophosphoric acid is a suitable method for the detal implant with bone-bonding ability.