TiO_2纳米管阵列的表面特性对猪肾小管上皮细胞生长状态的影响

Effect of Surface Characteristics of TiO_2 Nanotube Arrays on Porcine Renal Tubular Epithelial Cell Growth

TiO2纳米管阵列由于其优异的生物相容性及光催化效应,在生物医学领域引起了广泛关注.但能否将肾小管上皮细胞较好地黏附于TiO2纳米管材料并使其发挥肾小管的功能,目前还未见报道.为研究TiO2纳米管材料的表面特性对猪肾小管上皮细胞株(LLC-PK1)的黏附及增殖影响,采用阳极氧化法制备新型高强度的TiO2纳米管阵列,利用荧光显微镜考察了TiO2纳米管阵列光照特性、晶型结构及几何形貌参数对LLC-PK1细胞黏附的影响,采用MTT方法检测了黏附细胞的活性;同时使用扫描电子显微镜观察了4种不同管径上细胞生长的形态,并与纯钛片上细胞的生长形态进行对照.结果表明,管径为70nm的TiO2纳米管阵列膜最有利于LLC-PK1细胞的黏附及增殖,且细胞的活性最高;未经紫外光照射时锐钛矿型的TiO2比无定型更有利于细胞的黏附,然而锐钛矿型TiO2经紫外光照射后会导致细胞凋亡.扫描电子显微镜观察显示,细胞在纳米管上延伸为长条状,而在钛片上则呈堆积平板状.证实TiO2纳米管阵列膜具有良好的生物相容性,有助于改善细胞与材料的黏附.

TiO2 nanotube arrays are becoming increasingly more attractive for their excellent biocompatibility and photocatalytic properties in biomedical fields.However,no work has been reported on the adhesion characteristic of renal tubular epithelial cells to TiO2 nanotube film in order to fulfill a function of renal tubular.In the present study,novel titania nanotube arrays are fabricated on a pure titanium foil by means of the electrochemical anodization in this group.The effects of illumination performance,crystal structure,and geometry parameters of TiO2 nanotubes on the adhesion of Lewis-lung cancer porcine kidney 1(LLC-PK1) are investigated by fluorescence microscope.The cell viability is examined by MTT.Furthermore,the morphologies of cell growth on nanotubes with four various pore sizes are observed using filed emission scaning electron microscope(FESEM);micrographs for cell growth on the pure titanium foil are also provided as a contrast.The results show that the TiO2 nanotube arrays with pore size of about 70 nm have an advantage of optimal adhesion and proliferation for LLC-PK1 cell,and as a consequence giving higher cell viability.In comparison with the amorphous TiO2,the anatase nanotube arrays are more favorable to cell adhesion under a condition of the absence of UV irradiation;however,anatase TiO2 irradiated with UV light can cause apoptosis.SEM studies show that the LLC-PK1 cells grown on nanotube arrays have an elongated strip morphology,whereas cells grown on pure titanium foil exhibit the plate-like accumulation state.It demonstrates that novel titania nanotube array films have good biocompatibility,which can help to improve the cell adhesion.