COSMETIC LIQUID CRYSTAL EMULSIONS CONTAINING BRAZILIAN VEGETABLE BUTTERS

Abstract
Emulsions containing vegetable butters have especially attractive properties in cosmetic technology. They are used as vehicle for topical application. Apart from that, the natural raw materials have pharmacological activity, increasing the necessity for the development of new delivery systems for them.
The function of liquid crystals has been investigated mainly due to studies on the cell membrane and interest in research in the development of cosmetic products applied to the skin. Of immense importance was the elucidation of the composition of the protein lipid envelope that surrounds the corneocytes of the skin that are organized in the lyotropic lamellar liquid crystalline state.
In this way, the formation of liquid crystal by the components of the formulation allows the incorporation of water-soluble, lipo-soluble and amphiphilic drugs within these layers. Therefore, they are structures of great importance for the cosmetic and pharmaceutical industries, having different functions and that we can call "intelligent cosmetic forms" for the application of cosmetic products, mainly due to the structural similarity with the lipid protein envelope of the stratum corneum.
This skin's protein lipid envelope decreases transepidermal water loss and keeps the skin soft to the touch, with accentuated features of rejuvenated skin. This research aims to develop cosmetic products containing vegetable butters, to study the formation of liquid crystal and physical chemical stability under different storage conditions.
Then, O/W emulsions containing vegetable butters were developed at a fixed surfactant ratio and observed the formation of liquid crystalline phases. Surfactant system was consisted by Steareth-2 and Ceteareth-5. Emulsions were prepared by the emulsion phase inversion (EPI) method, presenting high stability independent on the HLB value. Results indicate that this method could be employed to attain stable emulsions, even if the required HLB value is not known

摘要

含植物油脂的乳液在化妆品技术中展现出尤为诱人的特性，它们被用作局部应用的载体。除此之外，天然原料具有药理活性，这进一步增加了开发新型递送系统的必要性。

液态晶体的功能主要因细胞膜研究以及应用于皮肤化妆品产品开发的研究兴趣而受到关注。阐明包围皮肤角质细胞（在液晶层状液晶状态下组织）的蛋白质-脂质包膜的组成具有重要意义。

通过配方成分形成液态晶体，使得水溶性、脂溶性以及两亲性药物能够融入这些层中。因此，这些结构对于化妆品和制药工业具有极大的重要性，并具有不同的功能。我们可以将这些结构称为‘智能化妆品形态’，主要归因于其与角质层脂蛋白包膜的相似性。

皮肤的蛋白质-脂质包膜能够减少经皮水分丢失，使皮肤触感柔滑，并突出肌肤年轻化的特征。本研究旨在开发含有植物油脂的化妆品，研究其在不同储存条件下的液态晶体形成及物理化学稳定性。

随后，在固定的表面活性剂比例下开发了含植物油脂的O/W乳液，并观察了液晶相的形成。表面活性剂系统由Steareth-2和Ceteareth-5组成。乳液通过乳液相转化（EPI）法制备，表现出与HLB值无关的高稳定性。结果表明，即使所需的HLB值未知，该方法也可用于制备稳定的乳液。