US EPA

180334 

Journal Article 

Nuclear microprobe study of TiO2-penetration in the epidermis of human skin xenografts 

Kertész, Z; Szikszai, Z; Gontier, E; Moretto, P; Surlève-Bazeiille, JE; Kiss, B; Juhász, I; Hunyadi, J; Kiss ÁZ 

2005 

1 

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
ISSN: 0168-583X 

231 

280-285 

10.1016/j.nimb.2005.01.071 

WOS:000229752400048 

Titanium-dioxide is a widely used physical photoprotective component of various cosmetic products. However, very few experiments have been carried out on its penetration through the human epidermal barrier and its possible biological effects in vivo and in vitro.
In the frame of the NANODERM EU5 project, the penetration of TiO2-nanoparticles through the epidermis of human foreskin grafts transplanted into SCID mice was investigated in the Debrecen and Bordeaux nuclear microprobe laboratories using combined IBA techniques. Transmission electron microscope studies of the same samples were also carried out in the DMPFCS laboratory.
The skin grafts were treated with a hydrophobic emulsion containing micronised TiO2-nanoparticles in occlusion, for different time periods. Quantitative elemental concentrations and distributions have been determined in 14?16 lm thick freeze-dried sections obtained from quick frozen punch biopsies using STIM, PIXE and RBS analytical methods.
Using both microscopic methods, we have observed nanoparticles having penetrated into the corneocyte layers of stratum corneum by direct visualisation in TEM and via their chemical fingerprint in PIXE.
The human skin xenograft has proved to be a model particularly well adapted to such penetration studies. 

ion microscopy; combined PIXE; STIM; RBS methods; electron microscopy; TiO2 nanoparticles; penetration into human skin