Insights into the Application of Reverse Micelles in Cosmetic Formulations: A Review

Reverse micelles are aggregates of amphiphilic molecules in nonpolar solvents. They have polar cores surrounded by surfactant head groups that can solubilize various hydrophilic compounds such as dyes, proteins, and antibiotics. They are frequently studied for extraction of organic and inorganic compounds. Advantages of reverse micelles are ease of production, high encapsulation efficiency, and protection of encapsulated compounds. The cosmetic market has been continuously growing over the years as more innovative cosmetics products are released into the market. Reverse micelles can be used as nano-sized carriers to encapsulate various hydrophilic active ingredients in cosmetic formulations. They can be prepared using safe, biocompatible, nontoxic, and biodegradable materials, thus are suitable to be incorporated into cosmetic products. The viscoelastic property and the skin permeation property can be adjusted. Targeted delivery and sustained release of active ingredients can be achieved through proper formulation. In addition to being directly included in formulations, reverse micelle systems are also used for the preparation of active ingredients and the analysis of cosmetic products for quality control. Therefore, reverse micelles show great potential for application in the cosmetic sector. This paper reviews related works in past two decades and provides some insights for future studies to broaden the implementation of reverse micelle systems in cosmetic products.