The use of animal testing in scientific research, in particular within the cosmetics industry, has long been criticized for its use in evaluating the safety and efficacy of ingredients and products. Since 2013, EU Regulation (EC) 1223/2009 has established a total ban on animal testing for cosmetic purposes. Therefore, these animal tests must be replaced in order to guarantee the safety and efficacy of cosmetic products, making it essential to find alternative methods that guarantee animal welfare. Some of these ethical options in the cosmetics industry include the use of in vitro assays, in which cosmetic products are tested on cell cultures, computer modelling, which can predict the effects of substances on health, and the use of synthetic human skin, which can reproduce many of the properties of real skin. All of these options represent a growing trend in the cosmetics industry.
Within this context, Dr Rocío Guerle Cavero recently conducted her doctoral thesis at IQS, within the Chemistry and Chemical Engineering department, entitled Creation of three-layer chitosan membranes to evaluate the anti-aging properties of active ingredients and products: an alternative to animal testing. Supervised by Dr Alberto Balfagón Costa, her thesis aimed to create a three-layer chitosan membrane ionically cross-linked with sodium tripolyphosphate in order to simulate different layers of human skin.
Dr Guerle focused her thesis, first of all, on the creation of the in vitro model formed by three-layer chitosan membranes, with induced pores to simulate the different characteristics and properties of human skin. Different types of chitosans with different degrees of deacetylation were studied, and she selected the one that best mimicked the different properties of skin and offered the best response to the properties studied.
Subsequently, she conducted a study of anti-aging properties for different active ingredients, products, and finished cosmetic products, which were tested in the new three-layer membrane that she created. Three of the main components of the extracellular matrix were studied: elastin, collagen, and hyaluronan, as well as one of the main components of the skin barrier, ceramides. She made a comparison between the incorporation of the different ingredients studied in the three layers, or in the target layers, to better understand how their placement affects the properties of the membrane.
Finally, she conducted clinical studies to evaluate the efficacy of certain active ingredients, products, and finished cosmetic products, using them as a reference to compare them with the results obtained with chitosan membranes.
In short, Dr Guerle’s thesis has demonstrated the potential of using three-layer chitosan membranes as a viable alternative to animal testing to evaluate the efficacy of different ingredients and finished products in the cosmetics sector. This biomimetic approach could help cosmetics, food, and pharmaceutical companies develop new products with specific properties without relying on animal experimentation.
Related publications
Guerle-Cavero, R.; Lleal-Fontàs, B.; Balfagón-Costa, A., Creation of Ionically Crosslinked Tri-Layered Chitosan Membranes to Simulate Different Human Skin Properties, Materials2021, 1–28.
Guerle-Cavero, R.; Balfagón-Costa, A., Study of Elastin, Hydrolyzed Collagen and Collagen-like Products in a Tri-Layered Chitosan Membrane to Test Anti-Aging Skin Properties, Int J Mol Sci2023, 24 (13), 1–31.
Galán-Navea, L.; Guerle-Cavero, R.; Balfagón-Costa, A.; Artalejo-Ortega, B., Creation of Chemically Tri-Layered Collagen Crosslinked Membranes and Their Comparison with Ionically Tri-Layered Chitosan Crosslinked Membranes to Study Human Skin Properties, Int J Mol Sci2023, 24 (13), 1–23.
