Influence Of Surface Characterizations On The Adhesion And Proliferation Properties Of Endothelial Cells

Implants will cause local tissue response and subsequently lead to such complications as hyperplasia. Thus, the interaction between the cells and biomaterials caused interests and the research work was carried out to find ways to restrain hyperplasia.In this research, the influences of crystalline structure, surface topography and electron structure on the cell adhesion and proliferation property were studied.Titanium dioxide (TiO₂) films with the different crystalline structure were prepared via sol-gel dip-coating method. The influence of humidity, substrate and catalyst acid on the film quality such as integrality and crystallization were investigated. Pure anatase-typed and rutile-typed TiO₂ films with homogeneous and compact nano-structure were prepared under the optimized conditions. Subsequently, the cell adhesion behavior of HUVEC was studied by means of immunofluorescent staining, and the cell proliferation was investigated by bicinchoninine acid (BCA) assay and MTT assay. The results show that the cell adhesion and proliferation property are both better on the anatase-typed TiO₂ film than that on the rutile-typed TiO₂ films. The possible reasons for above results were studied by surface energy test and infrared spectrum analysis. The results show that anatase-typed TiO₂ film shows a stronger capability to capture -OH radicle, which leads to better hydrophilicity which induce to the better cell adhesion and proliferation property.In the second part of this research, the adhesion and proliferation behavior of HUVEC on topographed-TiO₂ films were studied. One feasible method for the topographed-TiO₂ films' preparation was considered and subsequently applied via following procedures: Firstly, topographic patterns were designed and achieved on Si wafer by means of photolithography and reactive ion etching (RIE), and then titanium dioxide films were coated on them via sol-gel dip-coating method. The in vitro experimental results show the flat-area of the surface, as well as the space orientation, play an important role on the adhesion and proliferation behavior of cells. The cells exhibit better adhesion and proliferation behaviors on the surfaces on which larger flat-area is applied for the cells to stretch themselves.DLC films with different sp²/sp³ ratio were used to study the influence ofelectronic structure on the adhesion and proliferation behavior of HUVEC. The films were obtained by d.c. impulsed plasma deposition. The relative content of sp²/sp³ bonds was characterized by Raman spectrum instrument, and the result shows that the relative content of sp²/sp³ bonds is nonlinearly depended on the gas pressure of the chamber, as well as the species of the input gas. It seems that the content of sp² bonds is slightly increased when Ar was used to substitute Ar/C₂H₂.. The following cytological experimental results show that though the cell adhesion property decreases with the increasing of sp² bonds, the cell proliferation property seems no significant difference because the of the abnormal shape of the adhere cells.Overall, It can be concluded from this research results that the adhesion and proliferation properties of the cell will be restrained on the artificial surface whose crystalline structure leads to a hydrophobic result and whose surface topography can not applies enough flat-area for cells to freely attach and growth.