Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of Sao Paulo, Av. do Café s/n, 14040-903 - Ribeirao Preto, SP, Brazil.
Normandie Univ, UNILEHAVRE, FR 3038 CNRS, URCOM, 76600 Le Havre, France.
Int J Pharm. 2018 Dec 20;553(1-2):220-228. doi: 10.1016/j.ijpharm.2018.10.027. Epub 2018 Oct 11.
The objective of the present study was to develop, characterize and evaluate the clinical efficacy of topical formulations containing or not active substances and UV-filters, separate and in combination. To this end a stable formulation was developed to which four aqueous active substances and four lipophilic UV-filters were added. The formulations were then submitted to microscopic characterization by light microscopy, to particle size measurement, and to macroscopic characterization by rheology and texture analysis. Finally, a clinical efficacy study was conducted to determine the effect of the formulations on the skin after application for 1 h. The formulation containing UV-filters showed a high polydisperse microstructure and a large amount of liquid crystals. The formulations containing active substances showed higher resistance to deformation, compression and penetration tests. Regarding spreadability, formulations containing UV filters alone or in combination with active substances showed higher resistance to spreading. This behavior was associated with greater clinical efficacy in terms of stratum corneum water content, protection of the skin barrier function and skin surface brightness. It was demonstrated that the efficacy of the formulation is mainly associated with its structure and the way it interacts with the skin surface. Finally, this study showed that the mixture of these ingredients for the development of multifunctional sunscreens improves the performance of the formulations.
本研究的目的是开发、表征和评估含有或不含有活性物质和紫外线滤光剂的局部制剂的临床疗效，这些物质是单独或联合使用的。为此，开发了一种稳定的制剂，向其中添加了四种亲水性活性物质和四种亲脂性紫外线滤光剂。然后，通过光镜对制剂进行微观特征描述，通过粒度测量，通过流变学和质地分析对制剂进行宏观特征描述。最后，进行了一项临床疗效研究，以确定制剂在应用 1 小时后对皮肤的影响。含有紫外线滤光剂的制剂显示出高度的多分散微观结构和大量的液晶。含有活性物质的制剂表现出更高的抗变形、压缩和渗透测试的能力。关于铺展性，单独含有紫外线滤光剂或与活性物质联合使用的制剂显示出更高的抗铺展能力。这种行为与角质层含水量、皮肤屏障功能保护和皮肤表面亮度方面更高的临床疗效相关。研究表明，制剂的疗效主要与其结构以及与皮肤表面的相互作用方式有关。最后，本研究表明，这些成分的混合用于开发多功能防晒霜可提高制剂的性能。
