Change in Surface Chemistry of the Cuticle of Human Hair by Chemical and Photochemical Oxidation

The study investigated the damage to the hair fiber surface caused by photochemical and cosmetic chemical oxidative processes. Using unique techniques like microfluorometry and X-ray photoelectron spectroscopy, the researchers quantified and characterized the delipidation and acidification of the hair surface. They found that oxidation breaks down lipid domains on the cuticle, generating cysteic acid groups that can be tagged with Rhodamine B for quantification. The negative charges from oxidation can bind conditioning compounds, a process termed relipidation by adsorption. These changes affect surface wettability and fiber friction, impacting the spread and manageability of hair products.