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Attention to environmental issues has become increasingly important in recent years and also massively affects the cosmetics sector. In this context, sunscreens are questioned due to the proven or believed ecotoxicity of organic ultraviolet (UV) filters. This has pushed developers increasingly towards the use of inorganic filters, which can prove difficult to spread with low compliance. We faced the problem by proposing a rational approach based on the evaluation of the morphology of the inorganic material, as the real dimension does not often correspond to the characteristics declared by the producers because the material itself tends to aggregate. A combination of a specially selected inorganic filter is required to formulate Cosmetic Products with a Natural and Sustainable Connotation (CPCNS) standards.

Aim: We compared the performances of two different commercial products both based on betamethasone and an antibiotic but using different pharmaceutical vehicles: a polymer and lipid-enriched cream and a conventional oil-in-water emulsion. Methodology: Evaluation was conducted on a reconstructed human epidermis model. Moreover, skin barrier properties and cutaneous hydration of the two vehicles were evaluated on 20 human healthy volunteers. Results: Overall, the polymer and lipid-enriched formulation works as a film-forming product that retains the therapeutic agent for a long time, ensuring its penetration and absorption through the skin, and promoting skin hydration. Conclusion: The above characteristics are useful in the clinical setting, especially in the context of eczematous diseases with a strong xerotic component.

Skin cancer is the most common malignant cancer with an incidence of 1 million cases/year. It is well known that exposure to UV radiation from sunlight leads the most frequent risk factors for several skin disorders including skin cancer. Sunscreen filters represent a valid protection against dangerous effects derived from UV radiation, and they can be divided in organic and inorganic UV filters. Adding, at the product formulation, molecules with booster effect, or also substances that can increase the protecting effectiveness via synergic mechanisms, can further enhance their protection activity. Moreover, this approach leads to develop formulations with high SPF (Sun Protection Factor) with a reduced content of UV filters, this is in line with the recent decisions of yet a few countries (Palau, Thailand, Philippines, and Hawaii) to ban some sunscreen filters to preserve marine environments (i.e., reef). In this work, a new class of sunscreen UV filters has been synthesized, by means the combination of physical filter and Oxisol, an antioxidant molecule with booster effect. In this study, the synthesis of new physical multifunctional ingredients is reported, by means the direct surface functionalization of inorganic filters (in particular TiO2) with Oxisol. In this study, the full characterization of these multifunctional ingredients is also reported, in addition to the cytotoxicity tests, the photocatalytic activity and the rheological properties involved on skin application.

Objective The in vitro evaluation of SPF is still a problem due to the lack of repeatability and correlation between the in vitro and in vivo data and many authors are currently working to develop an internationally harmonized method.(1) Very recently, the use of several “adjuvant” ingredients such as boosters, antioxidants, immuno-modulators, solvents and film forming ingredients have further complicated the pattern for product developers, that should frequently run in vivo test. The aim of this study is to understand if a simple and cheap in vitro method could be optimized in order to provide both statistically repeatable and predictive SPF measurement. Methods In vitro SPF assessments were carried out on 75 commercial products. The SPF was measured according to two laboratory methods (A and B), using different substrates (PMMA and surgical tape Transpore™), quantity of product, spectrophotometers. In order to evaluate if a standard technique of spreading could lead to a statistically reliable result, we applied different spreading pressure (100 g and 200 g). Furthermore, we investigate if other parameters characterizing the product (SPF Category, Filter and Texture) might represent statically significant variables affecting the measures. We then compared the results obtained from in vitro SPF measure of 11 products to in vivo SPF, in order to assess the predictivity of in vitro methods. Results Several problems were encountered in confirming the weakness of the in vitro procedures. Pressure, SPF Category, Filter and Texture did not affect significantly the results. Overall best results were obtained with the B2 method that in terms of repeatability and predictivity provided statistically better results. Method A with Transpore™ tape showed better in vitro-in vivo correlation than Method B with PMMA plates. Conclusion In our investigation we demonstrated that it is possible for a single laboratory to optimize internal methods and protocols to achieve repeatable and predictive in vitro results, but it is extremely difficult to develop methods reproducible and equally reliable in different laboratories, probably due to “external variables” (eg. environmental, operator), which are difficult to control. This article is protected by copyright. All rights reserved.

The incidence of skin cancer is increasing both because of climate change and the increase in pollution than people&rsquo, s incorrect habits of sun exposure. In these regards, sunscreen and photoprotection are essential tools in consenting the benefits induced by safe solar light exposition and skin cancer prevention. In this work, a new class of sunscreen filter was synthesized by chemical combination of a physical filter (ZnO) and Oxisol (dihydroxyphenyl benzimidazole carboxylic acid), an antioxidant molecule with booster effect. In this work, a new class of filters with new properties was achieved by direct functionalization of particles surface. A full characterization of this multifunctional ingredient (ZnO&ndash, Ox) was conducted: Compared with the simple mixture, the new filter acts as a multifunctional molecule showing a higher Sun Protection Factor (SPF), a better cytotoxic profile (MTT and NRU assay), and anti-acne activity. A strong reduction of photocatalytic activity of ZnO was observed, also improving the safety profile.