Corneosurfametry: a predictive assessment of the interaction of personal-care cleansing products with human stratum corneum.

OBJECTIVE

Corneosurfametry is introduced as a noninvasive quantitative test rating the interaction between surfactants and human stratum corneum. It may be used as a predictive irritancy test.

BACKGROUND

Surfactants present in personal-care products elicit multiple effects on the stratum corneum. With upcoming regulations avoiding animal experiments and ethical considerations for human testing, there is a need for new in vitro methods evaluating irritancy.

DESIGN

Corneosurfametry entails collection of cyanoacrylate skin surface strippings and short contact time with surfactants followed by staining samples with toluidine blue and basic fuchsin dyes. Measurements are made by reading the color of samples using reflectance colorimetry.

RESULTS

The intensity of color increases with irritancy potential of the surfactant. Results are reproducible, and great differences are noted among a series of diluted shampoos, shower gels and facial cleansing gels.

CONCLUSION

Corneosurfametry is proposed as a rapid in vitro method allowing a predictive grading of surfactants related to irritancy.