Evaluation of a multiple microemulsion from Trichilia catigua extract and the percutaneous penetration through skin by Phase-Resolved photoacoustic spectroscopy.

Emulsion systems have been a breakthrough in cosmetic products, providing performance and effectiveness of products that use this technological strategy for drug delivery systems. In this sense, the microemulsion of the multiple emulsion W/O/W type containing a standardized extract of Trichilia catigua with high levels of polyphenols and antioxidants has great potential for cosmetic use. The aim of this study was to evaluate the formulations safety through the analysis of toxicity, comedogenicity, and histopathology in rabbits and apply the Phase-Resolved Photoacoustic Spectroscopy method to determine the formulation percutaneous penetration through the skin.