An attempt to determine protein denaturing potency of typical surfactants has been made by measuring specific rotation of bovine serum albumin. The potencies obtained were examined in relation to the intensities of skin roughness in vivo caused by the surfactants, and a noticeable correlation was found between them. This fact also suggested that the cause of skin roughness may be attributed to a certain extent to adsorption of surfactants. In addition, this technique is very useful in predicting the skin roughening potency of a surfactant without using human skin.

A New ABSTRACTA simple and accurate method for evaluating skin roughness caused by surfactants has been developed. The intensities of the roughness have been correlated with the chemical structures of surfactants by using this method. Results indicated in general, that the surfaetants having 12 carbons in their alkyl chain gave the skin more roughness than did those which had more or less than 12. The results obtained by this method were in good agreement with those from the immersion method usually used.