TiO2纳米管阵列粗糙度调控及其与蛋白相互作用

Interaction between proteins and roughness-regulated TiO2 nanotube arrays

采用电化学阳极氧化法,通过改变电解液氟离子浓度(0.4%、0.3%、0.2%(质量))和电压(15、25、35、45 V),制备一系列不同管径和粗糙度的TiO2纳米管阵列(TiO2 nanotube arrays,TNAs)。通过扫描电子显微镜以及原子力显微镜(atomic force microscopy,AFM)表征,结果表明随着电解液中氟离子浓度的降低,制备得到的TNAs表面平整度更好,壁厚增大,粗糙度降低。采用AFM力学表征研究了表面粗糙度以及管径对TNAs表面力学性质以及与细胞色素C(Cytochrome C,Cyt C)相互作用的影响,结果表明,黏附力与接触面积呈正比,随着TNAs管径增加,壁厚减小,TNAs与Cyt C的有效接触面积先增大后减小,两者之间作用力也先增加后减小;同时,同管径条件下粗糙度降低,TNAs有效面积增加,相互作用力也增加;由此可见,通过改变电解液氟离子浓度可以有效调控TNAs表面粗糙度及有效接触面积,进一步利于促进与蛋白分子之间相互作用。

A series of TiO2 nanotube arrays(TNAs)with different diameters and roughness were prepared by electrochemical anodization method by changing the fluoride ion concentration[0.4%,0.3%,0.2%(mass)]and applied voltage(15,25,35,45 V).The scanning electron microscopy(FESEM)and atomic force microscopy(AFM)results showed that the wall thickness of the prepared TNAs increased and the roughness decreased with the decrease of fluoride ion concentration in the electrolyte.The effects of surface roughness and diameter on the surface mechanical properties of TNAs and the interaction of Cytochrome C(Cyt C)were studied by AFM characterization.The results show that the adhesion is proportional to the contact area.With the increase of the diameter of the TNAs,the wall thickness decreases,the effective contact area between TNAs and Cyt C increases first and then decreases,and the forces of Cyt C with TNAs also increase first and then decrease.The roughness decreases when the diameter was fixed,the effective area of TNAs increases,and the interaction force also increases.It can be seen that the surface roughness and effective contact area of TNAs can be effectively controlled by changing the fluoride ion concentration of the electrolyte,which is further beneficial to promoting interaction with protein molecules.