The Effects Of TiO₂ Nanometer Thin Film On Lens Epithelium Cells

Objective To investigate the killing effect of photoexcited TiO₂ nanometer thin film on lens epithelium cells(LEC), and observe the adhesiveness and migration of LEC on the film.Methods TiO₂ nanometer thin films were prepared via the sol-gel method on glass plates. The LEC was cultured on the plates, naked plates as control. Under UVA (the mean exposure intensity: 0.184 mw/cm²) irradiation for 0, 10, 20, 30, 40 and 50 min respectively, the cell viability was tested by MTT, HE and AO-EB assay. The contact angle was measured on the plates, and the mean number of cell attached to the plates was calculated after cultured 24 hours. In wounding assay, LEC monolayers were subjected to scrape and the distance of cell migration after scraping 48 hours was measured.Results The photoexcited TiO₂ film exhibits LEC killing effect, which is increased with irradiation time. Exposing of cell to UVA more than 20min resulted in the membrane Webbing and shrinking of cell on TiO₂ film. With the exposure time increased, induced the cell membrane rupture, karyopyknosis, nucleolus disappear and the disintegration of cell. Under the fluorescence microscope, a lot of cell underwent apoptosis and necrosis after 20 min irradiation. The apoptosis rate(19.1%,P=0.017) and necrosis rate (92.1%,P=0.000) was significantly superior to those of the control group. The contact angle of the TiO₂ film was 0±2° , and that of...