The Application Of Titanium Dioxide Nanomaterials In Photocatalysis And Tumor Therapy

With the continuous progress of human society and the rapid development of science and technology,the problem of environmental pollution has become very serious.What is more,people living in the environment will generate inexplicable panic,the most disturbing of which is the"cancer panic".Therefore,environmental pollution and cancer problems have become the most pressing issues faced by humans.The development of nanotechnology provides new possibilities for solving the above problems.We used different organic acids as a surfactant and modified them to synthesize OA-modified TiO₂ material?OA-TiO₂?.We have shown that we synthesized anatase-type porous spheres by SEM,TEM,and XRD.The material,through BET test,has a specific surface area of 500 m²/g.Using infrared spectroscopy and XPS characterization,we propose a facile method to prepare a novel OA-modified TiO₂ material?OA-TiO₂?with carboxylate ligands derived from the oleic acid as the bidentate chelating linkage mode.Due to the combination of carboxylic acid ligands and the microscopic effects of porous spherical structures,the photocatalytic performance of OA-TiO₂ has been great improved.To demonstrate visible light photocatalytic activities,photocatalytic degradation of rhodamine B?RhB?and phenol was carried out to discuss the photocatalytic performance of the samples.The OA-TiO₂ sample exhibits excellent RhB photocatalytic efficiency with almost 100%degradation efficiency in 6 min,and t also exhibited excellent photocatalytic activity of phenol with 93%degradation efficiency in 180 min.To verify its photocatalytic stability,there was almost no attenuation in the four-cycle degradation of RhB experiments.By way of the oxidation of hydrogen peroxide,we synthesize a TiO_x material with a high surface area.Through the BET test,we can know that our material has a specific surface area of 681 m²/g.Due to its excellent photosensitivity,we applied it to cancer treatment.In vitro DOX drug loading TiO_x material showed the loading ratio of 100%.In the drug release experiment under different pH conditions,in the condition of pH=5,it is more conducive to drug release.Quantification of ROS generation from the NPs in response to X-ray irradiation was meassured using ROS Brite active oxygen fluorescence probe APF by means of fluorescence spectrophotometer.In addition,compared with TiO₂,the Ti Ox material showed remarkable ROS production upon X-ray irradiation.Owing to peroxidized by hydrogen peroxide surface of the TiO_x.So we think that TiO_x material have great potential in cancer treatment.In order to further explore the effect of TiO_x material in tumor therapy,we conducted in vitro experiments on TiO_x material and TiO_x/DOX.TiO_x material also showed excellent inhibition of cancer cells in response to X-ray irradiation,and the survival ratio of A549cancer cells can reach 50%detection by the Cck8 kit.Moreover,due to the synergistic effect of chemotherapy and radiotherapy,TiO_x/DOX showed higher cancer treatment in response to X-ray irradiation.At this time,the survival ratio of A549 cancer cells was only²7.38±1.8%.These data fully illustrated that TiO_x material was applied as an excellent drug carriers and X-ray photosensitizers in the future,and it can be used as an excellent drug carrier and X-ray photosensitizer.Combinations of chemotherapy and radiotherapy could be one of the most effective ways for the treatment of tumors.