title: Improving the selective cancer killing ability of ZnO nanoparticles using Fe doping.
abstract: This work reports a new method to improve our recent demonstration of zinc oxide (ZnO) nanoparticles (NPs) selectively killing certain human cancer cells, achieved by incorporating Fe ions into the NPs. Thoroughly characterized cationic ZnO NPs (∼6 nm) doped with Fe ions (Zn(1-x )Fe (x) O, x = 0-0.15) were used in this work, applied at a concentration of 24 μg/ml. Cytotoxicity studies using flow cytometry on Jurkat leukemic cancer cells show cell viability drops from about 43% for undoped ZnO NPs to 15% for ZnO NPs doped with 7.5% Fe. However, the trend reverses and cell viability increases with higher Fe concentrations. The non-immortalized human T cells are markedly more resistant to Fe-doped ZnO NPs than cancerous T cells, confirming that Fe-doped samples still maintain selective toxicity to cancer cells. Pure iron oxide samples displayed no appreciable toxicity. Reactive oxygen species generated with NP introduction to cells increased with increasing Fe up to 7.5% and decreased for >7.5% doping.
authors.affiliation: Department of Physics, Boise State University, 1910 University Dr., Boise ID 83725, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Thurber
authors.forename: Denise G
authors.initials: DG
authors.lastname: Wingett
authors.forename: John W
authors.initials: JW
authors.lastname: Rasmussen
authors.forename: Janet
authors.initials: J
authors.lastname: Layne
authors.forename: Lydia
authors.initials: L
authors.lastname: Johnson
authors.forename: Dmitri A
authors.initials: DA
authors.lastname: Tenne
authors.forename: Jianhui
authors.initials: J
authors.lastname: Zhang
authors.forename: Charles B
authors.initials: CB
authors.lastname: Hanna
authors.forename: Alex
authors.initials: A
authors.lastname: Punnoose
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005290:Ferric Compounds / Q000737:chemistry / Q000633:toxicity*; D005434:Flow Cytometry; D006801:Humans; D019169:Jurkat Cells; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015034:Zinc Oxide / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000970:Antineoplastic Agents; D005290:Ferric Compounds; D017382:Reactive Oxygen Species; C000499:ferric oxide; D015034:Zinc Oxide