(P 203) Improving Endothelial Cell Adhesion and Proliferation on Titanium by Sol-Gel Derived Oxide Coating

• Published in: Tissue engineering. Part A 2008-05, Vol.14 (5), p.863-863
• Main Authors: Chai, F, Ochsenbein, A, Winter, S, Traisnel, M, Breme, J, Hildebrand, H F
• Format: Article
• Language: English
• ISSN: 1937-3341; 1937-335X

In-stent restenosis becomes increasingly prevalent as a difficult-to-treat disease. An alternative therapeutic strategy to drug-eluting stents for that is enhancing, rather than inhibiting, endothelialization of metallic stent surfaces. In this light, the present study attempted to modify surface chemistry and topography of commercial pure titanium (cp-Ti) by different oxides (TiO sub(2), SiO sub(2), SiO sub(2)/TiO sub(2) and Nb sub(2)O sub(5)) coating via the sol-gel process that can probably improve endothelial cell adhesion and proliferation, therefore stimulate endothelialization without using any bioactive agents. The modified surfaces were then physicochemically characterized in the thickness, nano-scale topography and wettability, and biologically evaluated with the HPMEC endothelial cell line by cell counting, cell morphology and expression of focal adhesion molecules. Ellipsometry determined the thickness of oxide layers to approximately 100 nm; atomic force microscope revealed a nano-porous structure in the TiO sub(2) and Nb sub(2)O sub(5) layers and the Ra values ranged from 20 to 50 nm. The surface energy determined by sessile-drop method showed the highest polar component for SiO sub(2) (30.7 mJ/m super(2)) and the lowest for cp-Ti and 316L stainless steel (6.7 mJ/ m super(2)). In 3-day culture, the higher endothelial cell proliferation rates were found on SiO sub(2)/TiO sub(2), Nb sub(2)O sub(5) and TiO sub(2) than cp-Ti. TiO sub(2) showed a higher cell adhesion rate than cp-Ti in kinetic adhesion assay. These results offer an insight into that certain oxide coating processing could significantly improve endothelial cell adhesion and proliferation especially in early culture period, which will favor the endothelialization before the formation of smooth muscle capsules.