title: Role of particle coating in controlling skin damage photoinduced by titania nanoparticles.
abstract: TiO(2) nanoparticles hazard is associated to their photocatalytic activity causing release of DNA damaging ROS (Reactive Oxygen Species), lipid peroxidation and skin damage. Various coatings have been proposed to minimize photocatalysis, while keeping the potential to block UV radiations. Uncoated and variously coated commercial nano-titania have been classified on the basis of UVB-induced lipoperoxidation of linoleic acid. A selection of the most and the least protective specimens was then examined by ESR (Electron Spin Resonance) to evidence the presence of surface paramagnetic centres and the release of ROS in aqueous suspensions (spin trapping). Paramagnetic centres and ROS were correlated with the extent of lipid peroxidation. When tested on porcine skin (mimicking the human one), titania acted as on linoleic acid. The combined use of lipid peroxidation of simple fatty acids with ESR analysis is here proposed as a possible screening tool for the evaluation of the potential toxicity of nano-titania in sunscreen preparations.
authors.affiliation: Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Italy. eugenia.carlotti@unito.it
authors.forename: Maria Eugenia
authors.initials: ME
authors.lastname: Carlotti
authors.forename: Elena
authors.initials: E
authors.lastname: Ugazio
authors.forename: Simona
authors.initials: S
authors.lastname: Sapino
authors.forename: Ivana
authors.initials: I
authors.lastname: Fenoglio
authors.forename: Giovanna
authors.initials: G
authors.lastname: Greco
authors.forename: Bice
authors.initials: B
authors.lastname: Fubini
mesh_terms: D000818:Animals; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D004249:DNA Damage; D004578:Electron Spin Resonance Spectroscopy; D019787:Linoleic Acid / Q000737:chemistry / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects / Q000528:radiation effects; D053758:Nanoparticles / Q000737:chemistry*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D012867:Skin / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D019097:Spin Trapping; D013552:Swine; D014025:Titanium / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D020099:Coated Materials, Biocompatible; D017382:Reactive Oxygen Species; C009495:titanium dioxide; D019787:Linoleic Acid; D014025:Titanium