TiO_2纳米管阵列膜对牛血清白蛋白的吸附与脱附

Adsorption behavior of bovine serum albumin on titania nanotube arrays

采用电化学阳极氧化法以含氟的乙二醇溶液为电解液阳极氧化纯钛制备出排列规则的高长径比TiO2纳米管阵列膜,并用扫描电镜(SEM)、比表面积仪表征了TiO2纳米管阵列膜的形貌和比表面积。结果表明,所制得的TiO2纳米管阵列的管径约180nm,管长可达230μm,比表面积约59.8m2/g。以牛血清白蛋白(BSA)为药物蛋白分子的模型,并研究了TiO2纳米管阵列膜对BSA的吸附和脱附行为,考察了溶液pH值、BSA初始浓度和溶液离子强度对BSA吸附的影响与吸附态的BSA在不同pH值的PBS溶液中的释放行为。结果表明,BSA分子在其等电点(pH值=4.8)附近较容易吸附到TiO2纳米管上,吸附量随着BSA初始浓度的增加而增加,较高的离子强度会降低BSA的吸附,碱性条件下吸附态的BSA容易从TiO2纳米管上脱附,并由于纳米管的扩散限制效益呈现一定程度的缓释。

Highly ordered and uniform TiO2 nanotube arrays were fabricated by anodic oxidation of titanium foil in ethylene glycol containing NH, F and deionized water. The morphology and surface area of TiO2 nanotube arrays were characterized by scanning electron microscope（SEM） and specific surface area measuring instrument, respectively. The diameter, the length and the surface area of TiO2 nanotube arrays are, about 180nm, over 230f, m and 59.8m2/g, respectively. Then, the adsorption and desorption behavior of bovine serum albumin on TiO2 nanotube arrays were investigated. The results showed that the adsorption ability of bovine serum albumin was affected by pH value, initial concentration of BSA and ionic strength, respectively. The desorption of bovine serum albumin from TiO2 nanotube arrays were affected by pH value of PBS. Bovine serum albumin eas ily released from TiO2 nanotube arrays in alkaline conditions, and appeared diffusion limited benefits.