Abstract
Background: TiO2 nanoparticles (NPs) which are used in
sunscreen formulations are able to block ultraviolet (UV) radiation with a
higher efficiency compared with micro-scale particles. The concentration of
corresponding particles is an important factor in UV attenuation effects as
well as cell toxicity profiles. Herein, TiO2 NPs were dispersed
using ultrasonication treatment and a sunscreen cream was prepared using TiO2
NPs.
Methods: The
effect of TiO2 concentration (i.e. a physical barrier) and
octocrylene (i.e. a chemical UV filter) as well as sonication time (i.e.
aggregation preventer) were studied on UVB blocking efficiency of the
preparation by measurement of sun protection factor (SPF). Response surface
methodology was employed to investigate the effect of the inputs (independent
parameters) on the output (dependent parameter).
Results: Findings
indicated that maximum amount of nano-TiO2 and octocrylene make the
preparation most effective. The effect of ultrasonication in breaking the
agglomerates was however dominated by the effect of concentration of
octocrylene, possibly due to hydrophobic interactions between NPs and
octocrylene. Also, TiO2 NPs showed a significant increase in
cytotoxicity profile of the preparation.
Conclusion: In
conclusion, introduction of the nanoparticles, as the dominant factor, to the
sunscreen product increased both efficacy and cytotoxicity of the product.