Based on previous studies, it has been found that goji berry (GB), popularly known as a ‘miracle fruit’, has excellent antioxidant potential and can be used in the treatment of skin disorders associated with ageing. This study aimed to incorporate GB into a structured cosmetic in order to optimise its penetration. Stability studies of the formulation, determination of the antioxidant activity of the extract and of the formulation, rheological measurements, SAXS, polarised light microscopy and bioadhesion analyses were performed. The results indicated the antioxidant activity of the extract, which can be incorporated into an emulsified cosmetic formulation. The emulsified formulation containing the extract remained stable, even after being submitted to thermal and luminous stresses for 30 days. In addition, rheological tests revealed that the addition of the GB soft extract reduced the viscosity of the formulation, increasing thixotropy and deformation. These systems were characterised by SAXS as a lamellar phase, which was confirmed by polarised light microscopy. These highly organised structures indicate their excellent stability. In vitro bioadhesion experiments revealed that these formulations exhibited skin adhesion strength statistically similar to commercial anti-ageing formulation. These results suggest that this formulation has excellent potential to be used as a topical treatment for ageing.

ABSTRACT Guava (Psidium guajava L.) is a native fruit of the American tropics with commercial applications for its taste, flavor and aroma. Numerous pharmacological uses have been described for it, such as the antiseptic effect of its leaves, the use of the fresh fruit and tea from its leaves for the treatment of diarrhea, dysentery, diabetes mellitus, and others. However, considering its rich composition, the guava also is a potential source of antioxidants to be used in the development of new formulations for cosmetic and/or dermatological applications, the main focus of this research. Herein, we describe the study of the phytochemical composition and the antioxidant activity of a guava extract prepared with non-toxic solvents aiming its use at biological applications. High performance liquid chromatography and mass spectrometry were employed to identify the major components, while thermoanalytical measurements and hot stage microscopy were used to assess the chemical stability of guava fruit extract. The antioxidant activity was also evaluated assessing the SOD-like activity and ABTS free radical scavenger. The results show that the extract is a rich source of phenolic compounds, such as quercetin, kaempferol, schottenol, among many others. All of the components found in guava extract exhibit biological effects according to the literature data, mainly antioxidant properties.

Neste trabalho, os sistemas nanoestruturados com diferentes níveis de organização foram obtidos através dos diagramas de fase ternários, utilizando tensoativos com de diferentes graus de lipofilicidade, o PPG-5-Ceteth-20 e o Oleth 10, e ácido oleico e miristato de isopropila como fases oleosas. Através dos diagramas foi possível observar diferenças significativas relacionadas com as características dos sistemas, devido à capacidade que o Oleth 10 (como tensoativo) e o ácido oleico (como fase oleosa) têm em diminuir a tensão interfacial, facilitando a formação de uma extensa região de sistemas transparentes. Através da microscopia de luz polarizada foi possível identificar as características isotrópicas e anisotrópicas dos sistemas, sendo posteriormente confirmadas pelas curvas de dispersão de raios X de pequeno ângulo (SAXS). Além disso, foi possível verificar que o aumento de água nas formulações proporcionou maior estruturação, permitindo a observação de picos mais estreitos e definidos nas curvas de SAXS.

In this paper, nanostructured systems were developed, with the aid of ternary phase diagrams, from two surfactants, of differing degrees of lipophilicity (PPG-5-Ceteth-20 and the Oleth 10) and two oil phases (oleic acid and isopropyl myristate). It was observed that there were differences between the four resulting phase diagrams in the physical properties of the systems they represent. Thus, due to the capacity of Oleth 10 (as surfactant) and oleic acid (as the oil phase) to reduce interfacial tension, large regions of translucent systems were seen on the diagrams produced by them. By polarized light microscopy, it was possible to identify the isotropic and anisotropic properties of these systems, which were confirmed by small-angle X-ray scattering (SAXS) analysis. Furthermore, it was found that increasing the proportion of water in the formulations led to more highly organized structures, resulting in narrower and well defined SAXS peaks.

Sistemas poliméricos formadores de filmes representam uma nova e pouco explorada tecnologia em sistemas capazes de proteger a pele ou feridas e ainda liberar fármacos de forma controlada. Este trabalho teve como objetivo estudar o uso de materiais poliméricos híbridos ureasil-poliéter sintetizados pelo processo sol-gel como sistema formador de filmes contendo o fármaco modelo sulfadiazina de prata. O tempo de formação do filme pode ser controlado através da modificação da razão precursor/catalisador utilizada durante as etapas de hidrólise e condensação. Os resultados mostraram que a proporção precursor/catalisador influencia as características visuais do filme e o seu tempo de formação. A proporção precursor/catalisador igual a 20,8 m/v foi considerada ideal por proporcionar a formação de filmes homogêneos e transparentes em um tempo menor que cinco minutos. O perfil de liberação da sulfadiazina de prata é dependente das características das matrizes: matrizes mais hidrofóbicas como ureasil-POP levam a uma liberação lenta, devido principalmente ao baixo intumescimento da matriz. A matriz mais hidrofílica ureasil-POE possui grande capacidade de intumescer o quefavorece uma liberação mais rápida do fármaco. O conjunto de resultados apresentado revela a possibilidade de utilização futura destes sistemas no tratamento de feridas causadas por queimaduras.

Film forming polymeric systems represents a new and unexplored technology of systems forskin or wounds protection and for controlled drug release. The aim of this work was to study the use of polymeric organic-inorganic ureasil-polyether hybrids synthesized by the sol-gel process as film forming system containing silver sulfadiazine as model drug. The film formationtime can be controlled by changing the precursor/catalyst ratio used during the step of hydrolysis and condensations. The results showed that the precursor/catalyst proportion influences both the visual characteristics and time required to form the film. The precursor/catalyst ratio equal to 20.8 m/v was considered ideal due to promote the homogeneous and transparent film formation in less than 5 minutes. The release profile of sulfadiazine is dependent on the characteristics of the matrixes: matrix more hydrophobic as ureasil-POP provided a slowed released mainly due to the low swelling of the matrix. The more hydrophilic ureasil-POE matrix presents a large capacity to swell and favors the faster release of the drug. The set of results showed the possibility of future use of these systems for treating wounds caused by burns.

A preocupação com o câncer de pele hoje em dia vem crescendo cada vez mais principalmente em países tropicais, onde a incidência da radiação UVA/B é maior. O uso correto de protetores solares é a forma mais eficaz de prevenir o aparecimento desta doença. Os ativos utilizados em protetores solares podem ser filtros orgânicos e inorgânicos. Filtros inorgânicos apresentam muitas vantagens em relação aos orgânicos, tais como fotoestabilidade, ausência de irritabilidade e amplo espectro de proteção. Entretanto, em razão de apresentarem alto índice de refração, os ativos inorgânicos conferem aos protetores solares aparência esbranquiçada, diminuindo sua atratividade estética. Muitas alternativas têm sido desenvolvidas no sentido de resolver este problema e dentre elas pode-se destacar o uso da nanotecnologia. Estima-se que o uso de nanomateriais deve crescer das atuais 2000 para 58000 toneladas até 2020. Neste sentido, este trabalho tem como objetivo fazer a análise crítica abordando diferentes aspectos envolvidos tanto na obtenção de protetores solares inorgânicos (rotas de sínteses propostas nos últimos anos) quanto na permeabilidade, na segurança e em outros aspectos relacionados à nova geração de filtros solares inorgânicos.

Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years) and the permeability, the safety and other characteristics of the new generation of inorganic filters.

For the construction of the phase diagrams, the method of the aqueous titration was used. There were prepared 5 ternary diagrams, varying the surfactant and the oil phase. The liquid-crystalline phases were identified by polarized light microscopy. The formulations prepared with silicon glycol copolymer, polyether functional siloxane (PFS) and water (S1) and with diisopropyl adipate, PFS and water (S4) presented liquid-crystalline phases with lamellar arrangement. Moreover, after 15 days in hot oven (37 ºC), the formulations presented hexagonal arrangement, evidencing the influence of the temperature in the organization of the system.