Atomic force microscopy characterization of corneocytes: Effect of moisturizer on their topology, rigidity, and friction

Abstract

Background/purpose: Atomic force microscopy (AFM) is a novel technique for skin characterization. Objectives: To develop AFM tests for characterization of the outermost epidermis layer, corneocytes. As an example, the effect of moisturizer on the corneocyte properties is studied. Methods and materials:: Topology, rigidity, and friction (between individual corneocytes and AFM probe) of the top layer of corneocytes were measured by means of Veeco DM3100 AFM. Quench ™ moisturizing cream was applied daily on the forearm of five volunteers for a period of 9 days. The skin flakes were collected before and after the treatment using Cuderm tape strips. No additional treatment of flakes was performed before the measurements. Results: A protocol for the AFM study of corneocytes is developed. After the treatment, we observed overall smoothening of the corneocyte surface, an increase of friction, and a decrease of rigidity (the Young modulus). Conclusion: AFM can be used as a very sensitive tool for early detection of changes in corneocytes. © 2010 John Wiley & Sons A/S.