EX-VIVO PENETRATION OF NANOMETRIC ZnO and TiO2 ACROSS ACTINICALLY DAMAGED PORCINE SKIN: DEVELOPMENT OF AN ALBINISTIC SKIN PROTECTION TREATMENT

The skin penetration and safety of nanometric zinc oxide and titanium dioxide incorporated in a cosmeceutical cream, specifically designed to retard skin actinic damage in tropical Oculocutaneous albinism was investigated ex-vivo through simulated actinically damaged porcine skin. Franz diffusion cells were used in an experiment modeled in line with related work done by Diembeck et al (1999); the OECD guideline, document no 428 and the EU opinion SCCNFP 0750/03. The following experiment was distinguished by its use of simulated actinic damaged skin characteristic in albinism in the tropics. The subsequent analytical studies were modified, since skin stripping was not practical on damaged skin. Analysis for the nanomaterials was conducted on both the Franz cell receptor phase fluid as well as extractions from the entire skin tissue material after the diffusion process. Quantification analysis for the recovered titanium was done by ICP-AES and the zinc was assayed using Flame AAS. The total recoveries of zinc from the skin extracts ranged between101.35-103.20% of the total zinc applied. The amounts of zinc recovered were comparable in treated, untreated skin, and the receptor phase. Mean total recoveries of titanium for all categories ranged between 98.73% and 99.24%, of the total applied titanium. No titanium was found in the receptor phase. The results show that neither nanometric titanium nor zinc ions can penetrate both normal and actinically damaged porcine skin, thus, suggesting minimal systemic exposure when used in treatments for actinically damaged albinistic persons