Improved fluorescence staining technique for estimating turnover of the human stratum corneum

Abstract

The replacement time of the human stratum corneum of fifteen body regions was determined by measuring the days required for a strongly substantive fluorescent marker, Dansyl chloride, to disappear. Tbe horny layer was stained by a 24-h patch exposure to 5% Dansyl chloride (5-dimethylamino- 1-naphthalene-sulphonyl chloride) in petrolatum. In most body regions the renewal time for the horny layer was about 2 weeks, in agreement with the findings of other investigators. The advantage of Dansyl chloride over another compound, tetrachlorosalicylanilide, which has been used for this purpose, is that it is not an irritant.