不同纤维直径聚吡咯通电后对细胞和细菌黏附增殖的影响

Effects of different fibre diameter of polypyrrole after direct current stimulation on adhesion and proliferation of cells and bacteria

目的：研究不同纤维直径的导电高分子涂层材料聚吡咯通电后对细胞及细菌黏附增殖的影响。方法：含有聚吡咯涂层的钛片分为无电刺激组和加电刺激组,每组都有30~60 nm,70~100 nm,130~170 nm 3种直径的纤维。培养MC3T3细胞和金黄色葡萄球菌（Staphylococcus aureus,S.aureus）,分别接种于不同直径的聚吡咯纤维涂层表面,加电刺激组立即给予100 m V恒电压电刺激,持续时间1 h,以后每间隔24 h,给予电刺激1 h,无电刺激组不予处理。测量通电和不通电条件下各组细胞培养的CCK-8值、菌液的光密度（D）值,并用扫描电子显微镜和激光共聚焦显微镜观察培养细胞和细菌的黏附形貌。结果：通电组细胞的CCK-8值高于未通电组（F=12.248,P=0.006）,并且纤维直径越小,细胞的黏附和增殖情况越好（F=9.261,P=0.005）,通电组金黄色葡萄球菌的菌液D值低于未通电组（F=9.641,P=0.036）,纤维直径对细菌生长影响不显著。结论：聚吡咯涂层通电后可以促进细胞增殖,纤维直径小的涂层细胞生长更好;通电后可以抑制细菌增殖,不同纤维直径的材料表面细菌生长差异无统计学意义。

Objective：To study the effects of cells＇ and bacteria＇ s adhesion and proliferation on different fiber diameters of polypyrrole coating with electricity. Methods： Titanium coated with polypyr- role was divided into no electrical stimulation and stimulation groups, each group had 30 -60 nm, 70 - 100 nm, 130 - 170 nm diameters of the fiber. MC3T3 cells and Staphylococcus aureus （S. attreus） were inoculated on different fiber diameters of polypyrrole coating with and without electric stimulation . We gave the electrical stimulation group 100 mV for 1 h and every 24 hours gave it 1 h stimulation, and no e- lectrical stimulation group was not managed. We used scanning electron microscope （SEM） to observe the cells＇ and bacteria＇ s morphology. The cells were given 20 mL CCK-8 solutions after 1,3,7 days＇ cultivation, then incubated for 2 h, the solution was transferred to 96-well plate, we measured the ceils＇ CCK-8 of the 30 -60 nm, 70 - 100 nm, and 130 - 170 nm groups by Elisa. The cells on different fiber diameters were also stained by live-dead cell staining kit, TritonX-100 and DAPI. We used PBS to wash and glycerin to seal them. The live-dead situation and morphology were tested by co focal microscope. The bacterial were stained by Live/dead baclight bacterial viability kits, we detect the suspension＇ s D of the 30 -60 nm, 70 -100 nm, and 130 -170 nm groups, and also observed the bacteria＇s survival situa- tion by co focal microscope. Results： The CCK-8 of the cells with direct current stimulation was higher than that of the unpowered group （F = 12. 248, P =0. 006）. The smaller the fiber diameter, the better was the cell＇ s adhesion and proliferation （ F = 9. 261, P = 0.005 ）. The bacterial suspension＇ s D of the electric group was lower than that of the unpowered group, and the fiber diameter had no significant effect on the bacteria＇ s growth（ F = 9. 641, P = 0. 036）. Conclusion ： Polypyrrole coating with electricity can promote the cell＇ s proliferation and inhibit the bacteria＇ s proliferation, and the cell growth on small fiber diameter coating is better. There is no difference in the bacterial growth of different fiber diameter coatings.