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The Corneal Micropocket Assay: A Model of Angiogenesis in the Mouse Eye
Published on: August 16, 2014
Penetration enhancers assessed by corneoxenometry
V Goffin1, F Henry, C Piérard-Franchimont
1Belgian SSTC Research Center 5596, Department of Dermatopathology, University Medical Center of Liège, Belgium.
Skin Pharmacology and Applied Skin Physiology
|August 15, 2000
Summary
Corneoxenometry, a new bioassay, effectively measures chemical enhancer effects on skin barrier function. This method offers a rapid, cost-effective alternative to animal testing for assessing skin penetration and irritation potential.
Area of Science:
- Dermatology and Cosmetology
- Biophysical Chemistry
- Toxicology
Background:
- Chemical enhancers significantly impact the stratum corneum's barrier function through various mechanisms.
- Determining the synergistic or antagonistic effects of these enhancers in mixtures presents a significant challenge.
- Existing methods for assessing skin barrier alteration are often time-consuming and rely on animal testing.
Purpose of the Study:
- To evaluate the comparative effects of chemical enhancers, specifically ethanol and laurocapram, on skin barrier function.
- To assess the impact of a multi-component formulation containing N-acetyl-L-cysteine, urea, and salicylic acid on skin barrier properties.
- To validate Corneoxenometry as a reliable and rapid bioassay for predicting skin barrier alterations.
Main Methods:
- Corneoxenometry, a bioassay utilizing reflectance colorimetry, was employed to assess xenobiotic interactions with corneocytes.
- Comparative analysis of ethanol and laurocapram at various dilutions was conducted.
- A propylene-glycol-based gel formulation with varying concentrations of N-acetyl-L-cysteine, urea, and salicylic acid was tested.
Main Results:
- The Relative Index of Irritancy (RII) was calculated for each tested formulation.
- RII serves as a surrogate marker for lipid removal, stratum corneum disorganization, and protein denaturation.
- The study demonstrated Corneoxenometry's capability to quantify the effects of different chemical enhancers and formulations.
Conclusions:
- Corneoxenometry is a viable, cost-effective, and rapid alternative to traditional animal testing for evaluating skin barrier function.
- The bioassay provides a good prediction of barrier function alterations caused by chemical enhancers.
- This method aids in understanding the complex interactions of penetration enhancers and active ingredients in cosmetic and pharmaceutical formulations.
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