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Background:: The use of polymers in hair care products is widespread, and silicones in particular are extensively used in cosmetic formulations. In addition, plant oils can also be used for hair treatment. Objective: In the present work, oil-in-water (O/W) nanoemulsions were prepared to repair chemical damage to human hair samples, to investigate the combined use of a silicone polyether copolymer (surfactant) that has a branch composed of poly(ethylene oxide) in its chains, and two types of plant oils: coconut and ojon oil. Materials and Methods:: Surfactant-oil-water formulations were obtained by ultrasonic processing. The nanoemulsions were then applied to human hair strands previously damaged with sodium hydroxide, to compare the treated strands with untreated ones. The efficacy of the formulations was investigated by scanning electron microscopy, thermogravimetric analysis and mechanical tests. Results and Discussion:: Stables nanoemulsions were obtained with average size of the dispersed droplets up to 400 nm. The micrographs suggest that the action mechanism of the nanoemulsions depends not only on the type of plant oil used and size of the droplets dispersed in the system, but also on the type of hair that receives the treatment. The thermal analysis showed that the use of nanoemulsion changed the temperature of keratin interconversion to higher values, which can make hair fibers more resistant to heat. Hair resistance was improved when comparing virgin samples to the damaged ones. Conclusion:: The nanoemulsions were efficient in the treatment of the hair samples, which showed a significant improvement of their mechanical properties.

Os cosméticos antipoluição vêm ganhando cada vez mais destaque no setor de beleza, representados principalmente por produtos multifuncionais que buscam proteger a pele dos efeitos da poluição ambiental e da eletropoluição. Para compreender o estabelecimento dessa categoria de produtos no mercado, é necessário fomentar o conhecimento científico acerca dos mecanismos envolvidos na interação poluentes-pele, o que contribui para o desenvolvimento de cosméticos de fato eficazes e seguros. O objetivo central deste trabalho foi, portanto, elucidar os efeitos negativos da poluição ambiental (com destaque para o material particulado) e da exposição constante à luz visível na forma da luz azul presente nas telas de eletrônicos, bem como evidenciar estratégias utilizadas em cosméticos antipoluição para minimizar esses danos. O estudo foi conduzido a partir de uma revisão de literatura utilizando o protocolo PRISMA como ferramenta metodológica para orientar as etapas de busca, identificação, seleção e análise de artigos. Nesse contexto, a pesquisa foi norteada conforme as palavras-chave e realizada com base nos dados das plataformas Google Acadêmico, Scielo, PubMed e ResearchGate. De acordo com os dados apresentados, conclui-se que a tendência antipoluição vem se tornando uma prática cada vez mais recorrente e firme no mercado de cosméticos, o que justifica a necessidade da compreensão dos fatores envolvidos nesse conceito.

Vesicular nanosystems are versatile and they are able to encapsulate actives with different solubilities, such as lipophilic and hydrophilic compounds. The most well-known vesicular nanosystems are liposomes and niosomes, the last one is formed by non-ionic surfactants. In the present work, we developed photoprotective niosomes containing sunscreens (octyl methoxycinnamate, diethylamino hydroxybenzoyl hexyl benzoate and phenylbenzimidazole sulfonic acid), non-ionic surfactants, cholesterol and stearylamine (positive-charged lipid). Studies based on dynamic light scattering techniques, entrapment efficiency and morphology by transmission electron microscopy were performed to characterize the niosomes. In addition, rheology, pH, in vitro sun protection factor (SPF) efficacy and toxicity and in vivo and in vitro safety were determined for the niosome formulations F-N1 and F-N2. The mean sizes of N1 and N2 were 168 ± 5 nm and 192 ± 8 nm, respectively, and their morphologies were spherical, unilamellar and with an entrapment efficiency of more than 45% for each sunscreen. Both formulations, F-N1 and F-N2 presented characteristics of pseudoplastic non-Newtonian fluids, showing declining viscosity with increasing shear rate applied. SPF values were considered satisfactory, 34 ± 8 for formulation F-N1 and 34 ± 5 for F-N2. The formulations did not present toxicity when tested in macrophages and the pH was compatible with skin, which minimizes allergies. The in vitro safety assay showed lipophilic sunscreens greater affinity for the epidermis, since this layer contains natural lipids. In vivo safety assay suggests that the increased skin retention of N2 is directly correlated with the positive charge of stearylamine. Stable photoprotective niosomes were obtained and were shown to be promising nanostructures to be used against solar radiation.

The aim of this study was to develop and evaluate a corrective and photoprotective makeup for patients with dyschromias. An emulsion was prepared and pigment mixtures were incorporated in the formulation, producing five shades of corrective makeup: BEIGE (I, II, III), BRONZE and TAN. The sun protection factor (SPF) and UVA/UVB ratio of the corrective makeup were determined using spectrophotometry with a Labsphere ® analyser. The spreadability, occlusivity, stability, and photostability of the photoprotective formulations were also evaluated. For all formulations there was no statistical difference among them (p > 0.05) in terms of spreadability, occlusivity and SPF. They were considered to be photostable under solar radiation, with variations in SPF value and UVA/UVB ratio lower than 20%. The corrective makeup presented average-to-high UVB photoprotection and broad spectrum photoprotection. After 90 days, pH, density and SPF values showed no significant differences among formulations (p>0.05). All corrective makeup presented separation of the pigments, however, they returned to a homogeneous aspect and to the original color shade after shaking. The corrective makeup presented a fine texture, little brightness, and a homogeneous, dry-to-the-touch aspect. This work may benefit patients with dyschromias, improving their quality of life, besides promoting photoprotection and covering the skin blemishes.