| Popis: |
A systematic evaluation of a flow-through skin penetration chamber, obtained from Oak Ridge National Laboratory, was conducted by measuring in vitro cutaneous penetration with five organic chemicals: urea, caffeine, benzoic acid (BA), salicylic acid (SA), and acetylsalicylic acid (ASA). These hydrophilic test materials were selected for evaluation since it has been established by several investigators that the highly lipophilic compounds are difficult to study in any in vitro absorption system. They were also selected because of their known penetration of the skin of several species, including humans. Each chemical was applied in 5–10 µg/cm2 amounts as 14C-labeled chemicals in 10 µl volumes of acetone. The extent and rate of cutaneous penetration were compared using full-thickness skin from both HRS/J hairless mice and Fischer 344 rats. A rank order for the extent of penetration (percentage of dose absorbed over a uniform time period) was established using Fischer rat skin: caffeine > BA > SA > ur... |
