Evaluation of reagent effect on skin using time-of-flight secondary ion mass spectrometry and multivariate curve resolution

Chemical imaging and depth profiling of skin is useful for studying various biological phenomena. Although secondary ion images of biomolecules such as phosphocholine and cholesterol distributions on skin samples are easily obtained with time-of-flight secondary ion mass spectrometry (TOF-SIMS), the observation of proteins or minor ingredients is often difficult. In this study, TOF-SIMS imaging data of skin samples were analyzed with multivariate curve resolution (MCR) to obtain information on reagents applied to the middorsal skin of mice. The skin was sliced with a cryostat and placed on indium-tin oxide glass plates. The samples were measured with TOF-SIMS using Bi3++, and then the obtained data were analyzed with MCR. As a result, distributions of secondary ions related to the reagents were suggested by MCR results, although they were not obtained by a manual analysis using respective peaks. Copyright (c) 2012 John Wiley & Sons, Ltd.