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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22 Citations
Background Citations
2
Methods Citations
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22 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, Medicine
    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.
In vivo SPF and UVA-PF determination using (hybrid) diffuse reflectance spectroscopy and a multi-lambda-LED light source.
TLDR
A novel compact and adjustable DRS test system is presented, suggesting that the multi-lambda-LED device is suitable for in-vivo SPF testing based on the HDRS principle as well as for in -vivo UVA-PF measurements.
Skin rejuvenation: Biopolymers applied to UV sunscreens and sheet masks
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References

SHOWING 1-10 OF 52 REFERENCES
Methods for the Evaluation of the Protective Efficacy of Sunscreen Products
The objective of the present investigation was to examine the utilization of optical and spectroscopic methods for the noninvasive characterization of Anthelios XL Fluide Extreme (SPF 50+), an…
Comparison of human and porcine skin for characterization of sunscreens.
TLDR
The comparison of the USPF obtained for human and porcine skin results in a linear relation between both USPF values with a correlation factor R(2)=0.98, demonstrating the possibility for the use of porcines skin to determine the protection efficacy of sunscreens.
Influence of nonhomogeneous distribution of topically applied UV filters on sun protection factors.
TLDR
The development of a method to determine quantitatively in vivo the influence of homogeneity of the distribution of sunscreen containing UV filters on the sun protection factor (SPF) is developed.
Skin Penetration and Sun Protection Factor of Five UV Filters: Effect of the Vehicle
TLDR
By choosing the right vehicle or optimizing it, not only sunscreen products can be significantly improved in terms of pharmacological efficacy but the potential toxicological risk associated with the skin penetration of UV filters may be significantly reduced.
Percutaneous Absorption of Sunscreens Through Micro-Yucatan Pig Skin In Vitro
TLDR
Despite the highly lipophilic nature of sunscreens, particularly OMC, SC is the rate limiting skin layer for penetration and the ratio of SC content to the amount penetrated is a useful tool for evaluating sunscreen permeation.
Investigation of the homogeneity of the distribution of sunscreen formulations on the human skin: characterization and comparison of two different methods.
TLDR
Both methods were applied for the evaluation of three different sunscreen formulations for each method and a correlation of the homogeneity of distribution with the in vivo SPF could be confirmed.
Distribution of sunscreens on skin.
A New Method to Quantify the Application Thickness of Sunscreen on Skin
TLDR
The proposed method is a low cost, noninvasive method for the determination of SAT on skin and it can be used as a valid tool in field‐ and population‐based studies.
In vitro Sun Protection Factor: Still a Challenge with No Final Answer
TLDR
In vitro data were measured in this multicenter study to compare possible methodologies and strategies for an in vitro approach to the sun protection factor (SPF) and to point out which technical side effects may influence such a method.
Quantitative assessment of sunscreen application technique by in vivo fluorescence spectroscopy
For the first time, a method is described for measurement of surface density of sunscreen in vivo. Here, the method is used to measure the uniformity of sunscreen application. The intrinsic…
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