Film thickness frequency distribution of different vehicles determines sunscreen efficacy

@article{Sohn2014FilmTF,
  title={Film thickness frequency distribution of different vehicles determines sunscreen efficacy},
  author={Myriam Sohn and Adeline H{\^e}che and Bernd Herzog and Georgios Imanidis},
  journal={Journal of Biomedical Optics},
  year={2014},
  volume={19}
}
Abstract. Sun protection factor (SPF) frequently differs between sunscreens containing the same composition of ultraviolet (UV) filters that primarily define sunscreen efficacy. We tested the hypothesis that the thickness frequency distribution of the sunscreen film is also responsible for and can explain the divergence in the measured SPF. For this, we developed a method to measure film thickness from the difference of topography before and after application of 2  mg/cm2 of sunscreen on pig… 
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23 Citations
Background Citations
3
Methods Citations
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23 Citations

Citation Type

Citation Type

Calculation of the sun protection factor of sunscreens with different vehicles using measured film thickness distribution - Comparison with the SPF in vitro.
Oil Thickening with Organoclay Enhances the Ultraviolet Absorption Ability of Sunscreen on a Skin-mimicking Substrate.
TLDR
Thickeners, such as organoclay, increases the viscosity of the oil phase at a low shear rate after the high shear of application, which is an effective strategy for improving the overall quality and performance of sunscreen products.
Repartition of oil miscible and water soluble UV filters in an applied sunscreen film determined by confocal Raman microspectroscopy.
  • M. Sohn, Th. Buehler, G. Imanidis
  • Chemistry
    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology
  • 2016
TLDR
Repartition of the UV filters within the sunscreen film upon application is investigated for its role to affect sun protection efficacy and Confocal Raman microspectroscopy was shown to be a powerful technique for studying this mechanism of sun protection performance of sunscreens.
Development of a Synthetic Substrate for the in vitro Performance Testing of Sunscreens
TLDR
The possibilities of using alternative polymers for synthetic substrates for in vitro sunscreen testing are demonstrated, and four polymers showed a UV transmittance at 310 nm of more than 50%, as well as a total surface free energy close to the reported value for human skin.
Hybrid Diffuse Reflectance Spectroscopy: Non-Erythemal in vivo Testing of Sun Protection Factor
TLDR
For the first time a robust alternative test method of SPF- and UVA-PF values is described, taking into account the interaction of sunscreen formulation and skin, and due to the elimination of any erythemal relevant UVB and U VA doses, absolutely no skin reaction occurs.
Application of Factorial Design and Rheology to the Development of Photoprotective Formulations
TLDR
A quantitative relationship between wax concentration and significant responses was established, permitting the prediction of desirable rheological properties for improved sunscreen efficacy.
On the Validity of Beer–Lambert Law and its Significance for Sunscreens
TLDR
The results of this work show that the validity of the Beer–Lambert law is still given at the high concentrations at which UV absorbers occur in sunscreen films on human skin.
Skin Surface Topography and Texture Analysis of Sun-Exposed Body Sites in View of Sunscreen Application
TLDR
Different site-age combinations show significant variation of skin surface roughness, and the application of sunscreen may in some instances need to be adjusted to take into account the increased roughness of highly sun-exposed anatomical sites.
Skin rejuvenation: Biopolymers applied to UV sunscreens and sheet masks
Crystallization Velocity and UV Performance of Formulations With Oversaturated UV-Filter Content.
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