碱热处理对钛表面生物活性的影响

摘要

利用碱热法处理钛表面,部分样品加热到450和700℃进行热处理,获得不同形貌和不同晶型的TiO2薄膜.实验得出,未经热处理的样品表面以非晶态钛凝胶层为主,450℃热处理样品主要以锐钛矿相TiO2存在,700℃热处理样品主要以金红石相TiO2出现.700℃热处理后的样品表面分布有大量50nm左右的纳米颗粒,这些纳米粒子的尺寸效应能较好地诱导HA在样品表面沉积形成,提高细胞的黏附和增殖,因此表现出较高的生物活性.450℃热处理后的样品表面相对于未处理样品有更多的HA沉积,是因为表面层的晶型起了主要作用,即锐钛矿TiO2晶体比无定型凝胶态TiO2更利于诱导HA沉积.但相对于未经任何处理的空白样品,仅用NaOH处理后的样品表面较利于HA沉积,可能是碱处理后钛表面羟基增加,进而提高了其诱导HA沉积的能力.%The dioxide thin films with different morphologies and different crystalline on the surface of titanium was prepared by NaOH solution. Part of the samples were annealed at 450 and 700℃. Experimental results showed that the unannealed samples treated by alkali were mainly amorphous gel layer of titanium, annealed samples at 450℃ were anatase-TiO2 , annealed samples at 700℃ were rutile-TiO2. The annealed samples at 700℃ were good biological activity for the surface of 50nm-nanoparticles, which was favorable to hydroxyapa-tite formation, cell adhesion and proliferation for the nano-size effect. Annealed samples at 450℃ induced the rapider growth of hydroxyapatite than the not annealing samples for the anatase-TiO2. Namely, anatase-TiO2 is better to induce the hydroxyapatite deposition than the amorphous gel of titanium. Unannealed samples were better to induce the hydroxyapatite deposition than the titanium only polished with emery paper because of the rough morphology and the emergence of hydroxyl group (-OH).