Characteristics of titanium dioxide microdispersions with different photo-activity suitable for sunscreen formulations.

Characteristics of titanium dioxide microdispersions with different photo-activity suitable for sunscreen formulations.

International journal of pharmaceutics (2015-02-07)

L Kubáč, J Akrman, K Kejlová, H Bendová, K Klánová, Z Hladíková, P Pikal, L Kovaříková, L Kašparová, D Jírová

ABSTRACT

The aim of the study was the comparison of photo-activity of three types of titanium dioxide (TiO2) micro-dispersions intended for use as UV filters for cosmetic sunscreen products. The dispersions were also investigated with regard to their influence on the stability of photo-protective systems in cosmetic emulsions, their skin penetration/absorption and their photo-toxicity for humans and skin bacterial flora. All the tested micro-dispersions of rutile TiO2 type (agglomerates with diameter 120-150 nm), with primary particle size lower than 100 nm, demonstrated no phototoxic effect and insignificant antimicrobial behaviour. On the other hand, TiO2 with insufficient deactivation of photo-activity had significant negative impact on the stability of other organic UV filters and therefore on the stability of declared UV protective factors (SPF, UVA-PF). The study demonstrated that the level of deactivation of TiO2 is one of the highly important factors for evaluation of UV filters used as sunscreens.

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