Recebido em 16/1/08; aceito em 22/9/08; publicado na web em 15/4/09 DEVELOPMENT OF LIQUID-CRYSTALLINE SYSTEMS USING SILICON GLYCOL COPOLYMER AND POLYETHER FUNCTIONAL SILOXANE. 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 (S 1 ) and with diisopropyl adipate, PFS and water (S 4 ) presented liquid-crystalline phases with lamellar arrangement. Moreover, after 15 days in hot oven (37 o C), the formulations presented hexagonal arrangement, evidencing the influence of the temperature in the organization of the system.
BACKGROUND:Peeling is a procedure which aims to accelerate the process of
skin exfoliation.OBJECTIVES Development of formulations containing lactic acid at 85% or glycolic acid at 70%
and the evaluation of these formulations on clinical efficacy in reduction of fine
wrinkles. METHODS Preliminary stability tests were carried out and an in vivo
study was performed with three groups with 9 representatives each. One
was the control group, which used only sunscreen; another one used lactic
acid+sunscreen, and the last group used acid glycolic+sunscreen. Clinical efficacy
was assessed with a CCD color microscope, through the digitization of images
before and after treatment. The applications were carried out by a dermatologist,
once a mont h every 30 days, during 3 months. The area with wrinkles was
calculated by planimetry point counting, in accordance with Mandarin-de-Lacerda.
RESULTS The formulations were stable in the visual and Ph evaluation. There was no
improvement in the control group; for lactic acid, there was significant
improvement after the second peeling application on the outer lateral area of the
right eye and after the third application on the outer lateral area of the left
eye. For the glycolic acid group, there was significant improvement in the outer
lateral area of the left eye after the first application, and of the right eye
region, after three applications. The formulations used must be kept under
refrigeration and should be manipulated every 30 days. CONCLUSIONS Both peelings were effective in reducing fine wrinkles of the outer lateral eye
area after three applications (p≤0.05%). It was observed that peeling efficacy in
the external-lateral region of one eye might be different compared with that in
skin of the external-lateral region of the other eye, relative to the speed of
skin improvement.
The physicochemical attributes of emulsified systems are influenced by the characteristics of their internal phase droplets (concentration, size and morphology), which can be modified not only by the formulation components, but also by the analytical methodology employed. Thus, the aim of this work involved the physicochemical characterization of cosmetic emulsions obtained from different surfactants, as well as the introduction of the optical coherence tomography (OCT) as the analytical technique employed for the morphological characterization and particle size determination of the formulations. Three emulsions were prepared, differing at the type and concentration of the surfactant used, and their droplet sizes were evaluated through optical microscopy, laser diffraction and OCT. The microscopic analysis and the laser diffraction techniques provided an average particle size minor than 6.0 µm, not detected by the OCT technique, which could identify only bigger particles of the emulsified systems' internal phase. The results testify that OCT was suitable for the morphological characterization of cosmetic emulsions; however, the technique needs to be improved to ensure a better sensitivity in the analysis of smaller particles.Uniterms: Cosmetic emulsions/physicochemical characterization. Surfactants. Optical coherence tomography/morphological characterization. Optical microscopy/morphological characterization. Laser diffraction/morphological characterization.Os atributos físico-químicos de sistemas emulsionados são influenciados pelas características de suas gotículas de fase interna (concentração, tamanho e morfologia), as quais podem ser modificadas não apenas pelos componentes da formulação, mas também pela metodologia analítica empregada. Desta forma, o objetivo deste trabalho envolveu a caracterização físico-química de emulsões cosméticas obtidas a partir de diferentes tensoativos, bem como a introdução da tomografia de coerência óptica (OCT) como a técnica analítica utilizada para a caracterização morfológica e determinação do tamanho de partícula das formulações. Três emulsões foram preparadas, diferindo no tipo e concentração do tensoativo empregado, e seus tamanhos de gotícula foram avaliados por meio das técnicas de microscopia óptica, difração a laser e OCT. As técnicas de microscopia óptica e difração a laser forneceram tamanhos de partícula médios menores de 6.0 µm, não detectados pela técnica de OCT, que permitiu apenas a identificação de partículas maiores pertencentes à fase interna dos sistemas emulsionados. Os resultados reforçam a introdução da OCT como metodologia promissora para a caracterização morfológica de emulsões cosméticas; no entanto, a técnica requer aprimoramento para garantir maior sensibilidade na análise de partículas de menor tamanho.Unitermos: Emulsões cosméticas/caracterização físico-química. Tensoativos. Tomografia de coerência óptica/caracterização morfológica. Microscopia óptica/ caracterização morfológica. Difração a laser/ caracterização morfológica.
ensinamentos e valores transmitidos, pela bondade de ambos, pelo caráter, por sempre estarem ao meu lado, nunca medindo esforços para que eu pudesse alcançar meus sonhos. Às minhas queridas irmãs, pelos momentos de descontração, companheirismo e apoio, quando necessário; pelo carinho e alegria contagiante transmitidos pela
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