Ogwu A A, Okpalugo T I T, Ali N, Maguire P D, McLaughlin J A D
NIBEC, School of Electrical and Mechanical Engineering, University of Ulster at Jordanstown, Shore Road, Co. Antrim BT370QB, Northern Ireland, UK.
J Biomed Mater Res B Appl Biomater. 2008 Apr;85(1):105-13. doi: 10.1002/jbm.b.30922.
The biological response of human microvascular endothelial cells (HMEC-1) seeded on Si-DLC films and on control surfaces was evaluated in terms of initial cell enhancement, growth, and cytotoxicity. The microstructure of the films was characterised by Raman spectroscopy and X-ray photoelectron spectroscopy. The effect of changes in microstructure, surface energy, surface electronic state, and electronic conduction, on the biological response of the films to endothelial cells was investigated. Endothelial cell adhesion and growth was found to be affected by changes in the microstructure of the films induced by silicon doping and thermal annealing. We observed a significant statistical difference in endothelial cell count between the as-deposited DLC and Si-DLC films using the one sample t-test at a p-value of 0.05. We also found a statistically significant difference between the adhesion of HMEC films on DLC and Si-DLC films at various annealing temperatures using the one-way ANOVA F statistic test at p < 0.05 and the post-hoc Tukey test. One sample t-test at p < 0.05 of MTT-assay results showed the endothelial cells to be viable when seeded on DLC/Si-DLC films. We suspect that the increased adhesion of endothelial cells induced by increasing the amount of silicon in the Si-DLC films is associated with the development of a suitable surface energy due to silicon addition, which neither favored cell denaturing nor preferential water spreading before cellular attachment on the film surface. The presence of an external positively charged dipole on the Si-DLC films confirmed by our Kelvin probe measurements is also expected to enhance the adhesion of endothelial cells that are well known to carry a negative charge. The Si-DLC films investigated hold potential promise as coatings for haemocompatible artificial implants.
研究了接种在硅掺杂类金刚石碳（Si-DLC）薄膜和对照表面上的人微血管内皮细胞（HMEC-1）的生物学反应，包括初始细胞增殖、生长和细胞毒性。通过拉曼光谱和X射线光电子能谱对薄膜的微观结构进行了表征。研究了微观结构、表面能、表面电子态和电子传导的变化对薄膜与内皮细胞生物学反应的影响。发现硅掺杂和热退火引起的薄膜微观结构变化会影响内皮细胞的粘附和生长。使用单样本t检验，在p值为0.05时，我们观察到沉积态DLC薄膜和Si-DLC薄膜之间内皮细胞计数存在显著统计学差异。我们还使用单向方差分析F统计检验（p < 0.05）和事后Tukey检验发现在不同退火温度下，HMEC薄膜在DLC薄膜和Si-DLC薄膜上的粘附存在统计学显著差异。MTT分析结果的单样本t检验（p < 0.05）表明，接种在DLC/Si-DLC薄膜上的内皮细胞是有活力的。我们推测，Si-DLC薄膜中硅含量增加导致内皮细胞粘附增加，这与硅添加导致形成合适的表面能有关，这种表面能既不促进细胞变性，也不使水在细胞附着于薄膜表面之前优先铺展。我们的开尔文探针测量证实Si-DLC薄膜上存在外部正电荷偶极，这也有望增强已知带负电荷的内皮细胞的粘附。所研究的Si-DLC薄膜有望成为血液相容性人工植入物的涂层。
