成骨细胞在蛋白石/聚左旋乳酸复合材料膜上生长的研究

Study on Osteoblasts Growth on Opal Powder/Poly-L-Lactic Acid Composite Films

目的寻找新型生物医学支架材料。方法将能产生负离子的蛋白石粉末与常用的生物材料聚左旋乳酸(poly-L-lactic acid,PLLA)制成复合材料膜,在此膜上接种成骨细胞,采用扫描电镜和四甲基偶氮唑盐[3-(4,5-dimethyltyiazol-2-yl)-2,5-diphenyl tetrazolium bromide,MTT]法研究成骨细胞生长与增殖的情况。结果扫描电镜研究发现复合材料膜比PLLA膜更适合于成骨细胞的生长与增殖,MTT检测进一步证明了这一结果。研究认为蛋白石产生的负离子对细胞的生长与增殖有刺激促进作用。进而探讨了负离子对离体细胞作用的机理。结论成骨细胞在蛋白石/聚左旋乳酸复合材料上的生长状况良好,蛋白石释出的负离子对细胞的生长与增殖有促进作用。这一研究为开发新的医用支架材料提供了可能。

Objective To find a new material for biomedical scaffold. Methods Composite films from poly-L-lactic acid（PLLA） and opal powder were fabricated. Osteoblasts seeded on the composite films and control ones were examined. Cell densities and morphologies on these films were studied by scanning electron microscopy （SEM）. Cell growth and differential function were assessed by 3- （4,5-dimethyltyiazol-2-yl）-2,5-diphenyl tetrazolium bromide（M-R） test. Results SEM study showed that the addition of powder could improve the adhesion between osteoblasts and the composite films. MTT test proved that cell proliferation was improved when opal powder was added. This improvement came from the negative ion given off by the opal powder. The negative ions either accumulate at the cell membrane or enter into the cells. Accumulation of negative ions at the cell membrane leads to a change of electric potential difference across the cell membrane which should be in a proper range for the cells to perform their normal physiological function. If the negative ions enter the cells, they may take part in biochemical reactions whenever possible. In this way, the ions also affect the cell normal metabolism. Conclusion Osteoblasts grow well on opal/PLLA composites and the negative ion from opal powder is responsible for the enhancement of cell growth. This study provides a new material for biomedical scaffold.