Preparation and Evaluation in vitro of Usnic Acid Emulgel with Varying Concentrations of Propylene Glycol
Usnic acid is one of the secondary metabolites found in lichens. Usnic acid has anti-inflammatory activity and is classified as class 2 in the Biopharmaceutical Classification System (BCS), with low solubility but high permeability. Therefore, a suitable delivery system is needed to enhance the release and penetration...