Structural degradation at the surface of a TiO(2)-based nanomaterial used in cosmetics.

A number of commercialized nanomaterials incorporate TiO(2) nanoparticles. Studying their structural stability in media mimicking the environment or the conditions of use is crucial in understanding their potential eco-toxicological effects. We focused here on a hydrophobic TiO(2) nanoparticle-based formulation used in cosmetics: T-Lite SF. It is composed of a TiO(2) core, coated with two successive protective layers of Al(OH)(3), and polydimethylsiloxane. Soon after contact with water (pH = 5, low ionic strength), the T-Lite SF becomes hydrophilic and form aggregates. During this aging, 90%wt of the total Si of the organic layer is desorbed, and the PDMS remaining at the surface is oxidized. The Al(OH)(3) layer is also affected but remains sorbed at the surface. This remaining Al-based layer still protects from the production of superoxide ions from the photoactive/phototoxic TiO(2) core in our experimental conditions.

[1]  David B Warheit,et al.  Assessing toxicity of fine and nanoparticles: comparing in vitro measurements to in vivo pulmonary toxicity profiles. , 2007, Toxicological sciences : an official journal of the Society of Toxicology.

[2]  A. Whittaker,et al.  NMR study of the gamma radiolysis of poly(dimethyl siloxane) under vacuum at 303 K , 2002 .

[3]  G. Camino,et al.  Thermal polydimethylsiloxane degradation. Part 2. The degradation mechanisms , 2002 .

[4]  N. Tanaka,et al.  The photogenotoxicity of titanium dioxide particles. , 1997, Mutation research.

[5]  I. Fridovich,et al.  The utility of superoxide dismutase in studying free radical reactions. II. The mechanism of the mediation of cytochrome c reduction by a variety of electron carriers. , 1970, The Journal of biological chemistry.

[6]  F. Cazaux,et al.  Polydimethylsiloxanes with vinyl ether end-groups—I. Synthesis and properties as polymerizable wetting agents , 1995 .

[7]  H. Ringsdorf,et al.  Formation and characterization of self-assembled films of thiol-derivatized poly(dimethylsiloxane) on gold , 1997 .

[8]  H. Ukeda,et al.  Spectrophotometric assay for superoxide dismutase based on tetrazolium salt 3'--1--(phenylamino)-carbonyl--3, 4-tetrazolium]-bis(4-methoxy-6-nitro)benzenesulfonic acid hydrate reduction by xanthine-xanthine oxidase. , 1997, Analytical biochemistry.

[9]  Christine Ogilvie Robichaud,et al.  Estimates of upper bounds and trends in nano-TiO2 production as a basis for exposure assessment. , 2009, Environmental science & technology.

[10]  W. M. Heston,et al.  The Solubility of Amorphous Silica in Water , 1954 .

[11]  R. Baggs,et al.  Regression of Pulmonary Lesions Produced by Inhaled Titanium Dioxide in Rats , 1997, Veterinary pathology.

[12]  M. Urban,et al.  Reaction Sites on Poly(dimethylsiloxane) Elastomer Surfaces in Microwave Plasma Reactions with Gaseous Imidazole: A Spectroscopic Study , 1996 .

[13]  Tae-Hyun Bae,et al.  Effect of TiO2 nanoparticles on fouling mitigation of ultrafiltration membranes for activated sludge filtration , 2005 .

[14]  M. Wiesner,et al.  Chemical stability of metallic nanoparticles: a parameter controlling their potential cellular toxicity in vitro. , 2009, Environmental pollution.

[15]  José C. Ramalho,et al.  Photosynthetic Performance and Pigment Composition of Leaves from two Tropical Species is Determined by Light Quality , 2002 .

[16]  J. Ganor,et al.  Kinetics of gibbsite dissolution under low ionic strength conditions , 1999 .

[17]  Pratim Biswas,et al.  Role of Synthesis Method and Particle Size of Nanostructured TiO2 on Its Photoactivity , 2002 .

[18]  Thomas Lippert,et al.  Local chemical transformations in poly(dimethylsiloxane) by irradiation with 248 and 266 nm , 2006 .

[19]  Steffen Foss Hansen,et al.  Categorization framework to aid hazard identification of nanomaterials , 2007 .

[20]  Jean-Pierre Jolivet,et al.  Synthesis of brookite TiO2 nanoparticlesby thermolysis of TiCl4 in strongly acidic aqueous media , 2001 .

[21]  Stokes,et al.  A novel ex vivo technique to assess the sand/rub resistance of sunscreen products , 2000, International journal of cosmetic science.

[22]  D. Nahon,et al.  Speciation and crystal chemistry of Fe(III) chloride hydrolyzed in the presence of SiO4 ligands. 2. Characterization of Si-Fe aggregates by FTIR and 29Si solid-state NMR , 2001 .

[23]  Wanqin Jin,et al.  Polydimethylsiloxane (PDMS)/Ceramic Composite Membrane with High Flux for Pervaporation of Ethanol−Water Mixtures , 2007 .

[24]  Thomas Lippert,et al.  Photochemical Modification of Cross-Linked Poly(dimethylsiloxane) by Irradiation at 172 nm , 2004 .

[25]  R Atkin,et al.  Mechanism of cationic surfactant adsorption at the solid-aqueous interface. , 2003, Advances in colloid and interface science.

[26]  Diffey Bl,et al.  A novel ex vivo technique to assess the sand/rub resistance of sunscreen products , 2000 .

[27]  G. Lucovsky,et al.  Infrared spectroscopic study of SiOx films produced by plasma enhanced chemical vapor deposition , 1986 .

[28]  Mihail C. Roco,et al.  International strategy for nanotechnology research and development , 2001 .

[29]  B. Nowack,et al.  Exposure modeling of engineered nanoparticles in the environment. , 2008, Environmental science & technology.

[30]  G. Bartosz Use of spectroscopic probes for detection of reactive oxygen species. , 2006, Clinica chimica acta; international journal of clinical chemistry.

[31]  Ivana Fenoglio,et al.  Role of particle coating in controlling skin damage photoinduced by titania nanoparticles , 2009, Free radical research.

[32]  D. Neivandt,et al.  Interference Effects in Sum Frequency Vibrational Spectra of Thin Polymer Films: An Experimental and Modeling Investigation , 2004 .

[33]  Roland W. Scholz,et al.  Exposure modeling of engineered nanoparticles , 2009 .

[34]  J. Hollahan,et al.  HYDROXYLATION OF POLYMETHYLSILOXANE SURFACES BY OXIDIZING PLASMAS , 1970 .