title: Surface chemistry influences cancer killing effect of TiO2 nanoparticles.
abstract: Photocatalyzed titanium dioxide (TiO2) nanoparticles have been shown to eradicate cancer cells. However, the required in situ introduction of ultraviolet light limits the use of such a therapy in humans. In the present study the nonphotocatalytic anticancer effect of surface-functionalized TiO2 was examined. Nanoparticles bearing -OH, -NH(2), or -COOH surface groups were tested for their effect on in vitro survival of several cancer and control cell lines. The cells tested included B16F10 melanoma, Lewis lung carcinoma, JHU prostate cancer cells, and 3T3 fibroblasts. Cell viability was observed to depend on particle concentrations, cell types, and surface chemistry. Specifically, -NH(2) and -OH groups showed significantly higher toxicity than -COOH. Microscopic and spectrophotometric studies revealed nanoparticle-mediated cell membrane disruption leading to cell death. The results suggest that functionalized TiO2, and presumably other nanoparticles, can be surface-engineered for targeted cancer therapy.
authors.affiliation: Bioengineering Department, University of Texas at Arlington, Arlington, Texas 76019-0138, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Thevenot
authors.forename: Jai
authors.initials: J
authors.lastname: Cho
authors.forename: Dattatray
authors.initials: D
authors.lastname: Wavhal
authors.forename: Richard B
authors.initials: RB
authors.lastname: Timmons
authors.forename: Liping
authors.initials: L
authors.lastname: Tang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D051379:Mice; D053758:Nanoparticles; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; C009495:titanium dioxide; D014025:Titanium