可见光响应掺氮TiO2的制备及对白血病HL60细胞体外杀伤效应的研究

采用硫酸钛与氨水反应制备掺氮TiO2。UV-Vis漫反射谱研究表明掺氮的TiO2在紫外区的吸收边明显红移（约20nm），并且在400nm-530nm出现新的吸收区域，光吸收阈值从380nm扩展到530nm。XPS分析表明，在TiO2掺杂的N为间隙态，而且还存在大量的氧空位。氧空位在导带下形成的窄带使得掺氮的TiO2在400nm～530nm出现新的吸收区域。用MTT法测量了掺氮TiO2杀伤白血病HL60细胞的活性。结果显示，无论有无可见光照射，掺氮TiO2对白血病肿瘤细胞杀灭效果明显好于未掺杂TiO2。

Study on Preparation oF Visible Light-Activated Nitrogen-Doped TiO2 and Its Photodesdrucing Effect on Leukemic HL60 Cells in Vitro

Nitrogen-doped TiO2 was prepared by Ti(SO4)2 solution reacting with NH3 aqueous solution. The optical absorption edge of nitrogen-doped TiO2 shifted 20 nm toward the infrared and also absorbs the visible light from 400 nm to 530 nm compared with undoped TiO2.Band gap of undoped TiO2 was 3.24 eV and nitrogen-doped TiO2 was 3.14 eV. X-ray photoelectron spectroscopy(XPS) measurements show that the nitrogen in N-doped TiO2 is in dissociative interstitial state. That the new absorption band at 400 nm ~530 nm is induced by oxygen vacancies in N-doped TiO2, which exhibits a narrow band close to the conduction band. The MTT assay was used for detecting the activity of N-doped TiO2 on the growth of leukemic HL60 in vitro. The results indicate that N-doped TiO2 can improve the efficiency of destructing leukemic HL60 cells no matter there is or not visible-light irradiation.