Molecular Concentration Profiling in the Skin Using Confocal Raman Spectroscopy

The uppermost layer of skin – the stratum corneum (SC) – plays a vital role in the functioning and protection of the human body. It provides mechanical protection and regulates water movement in and out. Despite the relatively small dimensions of the SC over most of the body parts(its thickness is of the order of 20 μm over a large portion of the body), it is far from a homogeneous structure both physically and chemically. Chemical concentrations change from its surface inwards, and these changes are responsible for both the properties it possess and the processes occurring within it. Furthermore, with the application of topical cosmetic products becoming more popular and widespread, especially in the anti-aging market, the monitoring of ingredients that are capable of penetrating into the skin from the outside, which may also influence the processes occurring within and properties of the SC, is now a necessity.