An evaluation of barrier repair foam on the molecular concentration profiles of intrinsic skin constituents utilizing confocal Raman spectroscopy

J Clin Aesthet Dermatol. 2012 Aug;5(8):14-7.

Abstract

For decades, transepidermal water loss and corneometry have been accepted as measures of skin barrier function. However, these tests are not capable of informing clinicians of the biochemical constituents and biophysical status of the stratum corneum. Knowledge of how the stratum corneum reacts to topical agents is important, as it reveals significant detail regarding the composition and function of this vital skin layer. Furthermore, transepidermal water loss and corneometry serve only as surrogate markers of barrier function. A more precise method of assessing stratum corneum hydration and lipid levels is emerging; in vivo confocal Raman spectroscopy is able to detect and quantify specific biochemical constituents in skin. This information then allows for assessment of the actual physiological status of this vital layer of the skin. This pilot study sought to elucidate a biophysical rationale for the clinical improvement achieved by hyaluronic acid/ceramide barrier repair foam in prior studies as measured by in vivo confocal Raman spectroscopy. Study results include increased lipid and hydration levels in the stratum corneum to depths of 25µm and 40µm, respectively, at the 2-hour, 48-hour, and 7-day time points.