Study of interactions between Gallic Acid and Skin Surface using Infrared Spectroscopy

•Differentiation of treated and untreated skin samples by chemometric methods.•Non-linear character of prediction model for kinetic data of untreated skin.•Systematic kinetic changes of the skin after treatment by solutions of gallic acid.•Crucial role of gallic acid, minor effects of solvents on skin changes.•Gallic acid could be a potential penetration enhancer.