Hair and nail water-holding capability measurements by using condenser-TEWL method

Abstract

We have developed a new method for studying human hair and nail water-holding capabilities by using the condenser-chamber trans-epidermal water loss (TEWL) method. Healthy hair and nail always contain certain amount of water, and they will lose this water to the environment naturally through evaporations. We monitored this desorption process by continuously measuring the water vapour flux density from hair and nail using the condenser-TEWL method, which is a condenser-based closed-chamber TEWL technology that is particularly suitable for this kind of measurements. We have also develop mathematical models for modelling the hair and nail desorption process. By fitting the normalized hair and nail desorption data with the mathematical models, we can get the water diffusion coefficient information, which can then be related to the water-holding capabilities of the hair and nail samples. © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.