Study On The Controllable Construction Of Micropattern Titanium Dioxide Nanotubes Biomaterial And Its Biological Properties

In the field of biomedical materials,the interactions of cells and biomaterials has become a very active area of research,how to effectively guide and control the cells adhesion on the materials surface is a key problem.In recent years,micropatterned biomaterials have aroused great interest of researchers.The surface nano and microscale features of micropatterned biomaterials could precisely guide and control cell adhesion,spreading,proliferation and differentiation.It has broad application prospects in the fields of cell biosensor,drug screening,in vitro tissue reconstruction and cell basic biology.There are many micropatterning technologies to modify the surface of biomaterials,mainly on the surface of glass,ceramics,metal and polymer substrate.Constructing the micropatterned biomaterials with excellent biological micropatterned biomaterials,is a core research subject and direction in the field of biomaterials and tissue engineering.In the present work,we focused on the development of photolithography technique,hydrothermal treatment technique and heat-treatment technique to construct successfully anatase titanium dioxide?TiO₂?nanotubes micropatterns with a uniform nano/micro multiscale structure on Ti substrates.Qualitative analysis of bovine serum albumin?BSA?adsorption in TiO₂ micropatterns were analyzed.In addition,the effects of microstructure,wettability,micropattern size and spatial arrangement on the selective adhesion and directional growth behavior of the preosteoblast MC3T3-E1 were also investigated.The main results of this dissertation are outlined as following:?1?The high quality photoresist micropattern with clear boundary was successfully constructed on the surface of the medical metal titanium substrate by photolithography technique.Based on this photoresist micropatterned template,the titanium dioxide micropattern with nano/micro multiscale structure was finally constructed on the surface of the metal titanium surface by combining the hydrothermal treatment technique and heat-treatment technique.The striated titanium dioxide nanotubes micropattern with different sizes?200×200?m,200×100?m,100×100?m,50×100?m?were prepared by controlling the micropattern of the photoresist.It indicates that by controlling the size of the micropattern template of the photoresist,the precise control of the micropattern size of titanium dioxide nanotubes can be achieved.?2?Qualitative research of protein adsorption showed that microtubulization nanotubular titanium dioxide micropattern can improve the protein adsorption due to the large specific surface area of nanotubes and microporous composite structures.FITC-BSA selectively adsorbed on the of micropatterned titanium dioxide nanotube micro-area and formed strip micropattern.Moreover,the BSA adsorbed quickly on the surface of the micropatterned samples,and it could form a clear BSA micropattern consistent with the substrate micropattern after adsorption for 2h.?3?The results of in vitro cell culture experiments indicated that the micropatterned titanium dioxide material with nano/micro multiscale structure can effectively guide the cells to selectivity adhered on superhydrophilic titanium dioxide nanotubes surface with strip pattern,and the size of cell pattern was almost the same as substrate size.It is due to the superhydrophilic surface,and combination of internal connected micro porous structure plus nanoscale tubular structure,to provide sufficient anchoring space and adequate nutrient growth microenvironment for cell growth.?4?The results of cell culture experiments on the surface of micropatterned titanium dioxide nanotubes with different sizes showed that with the size of the stripe micropattern decreasing,significant cells elongation along the direction of pattern.And the cell angle and stripe pattern was in parallel.Cell shape showed anisotropy specific.When the micropattern size was reduced to 50×100?m,the cell growth orientation showed the most significant.It is indicates the orientated growth behavior of cells can be effectively regulated by controlling the shape,size and space arrangement of the micropattern.