Formulation and Evaluation of Valproic Acid Microemulsions for Enhanced Transfollicular Delivery in Guinea Pig Skin
November 2024
in “
Journal of Cosmetic Dermatology
”
This study focused on developing and evaluating microemulsion (ME) formulations of valproic acid (VPA) for improved transfollicular delivery in guinea pig skin. Eight stable ME formulations were created, featuring droplet sizes of 10 to 24 nm and pH levels between 4.6 and 5.2. These formulations demonstrated controlled release over 24 hours and enhanced drug delivery through both follicular and nonfollicular pathways compared to an aqueous VPA solution. The study found that formulations with higher surfactant/cosurfactant ratios improved permeation through the follicular pathway. The composition of the MEs, including oil and water content and surfactant/cosurfactant ratio, was crucial in determining the physicochemical properties and skin permeation of VPA.