Enhancing effect of absorption promoters on percutaneous absorption of a model dye (6-carboxyfluorescein) as poorly absorbable drugs. I. Comparison of plasma levels after addition of various absorption promoters in rat.
We have investigated the promotive effect of various agents on percutaneous absorption of 6-carboxyfluorescein (CF), a water-soluble fluorescent dye, as poorly absorbable drugs. The absorption of CF was determined by measuring rat plasma CF levels. As an absorption promoter, several reagents such as surface-active agents, protein solubilizers and permeation promoters were used. The used concentration of the reagents was determined so as not to make a trauma on the skin. As results, plasma CF levels following the co-administration of 0.05 w/v% sodium dodecyl sulfate and 0.1 v/v% 2-mercaptoethanol showed the highest values. Plasma CF level was increased 40 times as compared to that of control experiment and was increased 9 times as compared to that of pretreatment with 4 w/v% calcium thioglycolate which was reported previously as a strong absorption promoter for theophylline by us. When the stratum corneum, having a barrier function for percutaneous absorption of many compounds, was removed mechanically, plasma CF levels of control experiment and pretreatment with 4 w/v% calcium thioglycolate were increased remarkably. However, plasma CF level after the co-administration of 0.05 w/v% sodium dodecyl sulfate and 0.1 v/v% 2-mercaptoethanol did not show a considerable difference as compared to that of the case with the presence of the stratum corneum.
D000287:Administration, Topical; D000818:Animals; D004396:Coloring Agents / Q000378:metabolism*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005452:Fluoresceins / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D008297:Male; D008623:Mercaptoethanol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012869:Skin Absorption / Q000187:drug effects*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D013864:Thioglycolates / Q000494:pharmacology; D014508:Urea / Q000494:pharmacology
D004396:Coloring Agents; D005452:Fluoresceins; D013864:Thioglycolates; C024098:6-carboxyfluorescein; D012967:Sodium Dodecyl Sulfate; D008623:Mercaptoethanol; D014508:Urea; D004121:Dimethyl Sulfoxide