THE INFLUENCE OF DIMETHYL SULPHOXIDE ON THE PERCUTANEOUS MIGRATION OF POTASSIUM DODECYL [45S] SULPHATE

SUMMARY.— The results obtained in the present communication are consistent with the view that the primary resistance zone to the percutaneous migration of potassium dodecyl [⁴⁵S] sulphate from aqueous, unbuffered solutions across human skin samples resides in the horny layer. It is further proposed that a secondary resistance zone is present in the combined epidermal and dermal regions. Application of the $$S-lablelled ester in dimethyl sulphoxide in a concentration range 50 100% did not influence the rate of migration. By contrast, pretreatment of isolated horny layers by total immersion in 100% dimethyl sulphoxide for four hours at temperatures up to 60 C, markedly reduced the barrier function. Control experiment involving pretreatment in water were without effect. Pretreatment of whole skin samples in position in the diffusion cells using 100% dimethyl sulphoxide at temperatures up to 60 C, did not reduce the capacity of the barrier towards potassium dodecyl [⁴⁵S] sulphate.