Characterization by Raman and infrared spectroscopy and fluorescence microscopy of human hair treated with cosmetic products

•The permeation of cosmetics in the hair fiber was analyzed by spectroscopy.•Both Raman and fluorescence techniques support the permeation trough hair fibers.•It was observed with Raman spectroscopy that the concentration of the products is found mainly in the cuticular region.•The analyzed cosmetics contained in their compositions components such as lipids, hydrolyzed protein, amino acids and silicones.•The permeation content of the products in the hair fiber decreases towards the medulla.