Development of Hair Analysis Methods by MALDI-TOF-MS and MALDI-MSI and Evaluation of Cosmetic Treatments

This study developed a method using mass spectrometry imaging technique (MALDI-MSI) to analyze the incorporation of cosmetics, specifically argan, avocado, and coconut vegetable oils, into hair. The oils were initially characterized by GC-MS, GC-FID, direct injection into ESI-MS, and comparison with MALDI-TOF-MS. The application of the MALDI-TOF-MSI technique allowed the evaluation of the permeation of oils in hair fibers, with a maximum standard deviation of 0.08 Da for 10 repetitions (avocado oil). The study found signs of direct incorporation of components of these oils and changes in the hair cortex and surface after treatment, proving that the oils are incorporated into the hair during treatment. This suggests the effectiveness of using oils in cosmetic formulations and their potential use in specific treatments, such as preventing alopecia. The developed method was able to generate images of the spatial distribution of ions in the hair cortex, confirming changes in the hair cortex after treatments.