DIRECT IMAGING OF MOLECULAR-TRANSPORT THROUGH SKIN

Scanning electrochemical microscopy (SECM) was used to image spatial v ariations in the molecular flux of Fe(CN)(6)(-4) across excised hairle ss and nude mouse skin. The SECM response is specific to electroactive molecules, allowing selective imaging of the flux of Fe(CN)(6)(-4) in multicomponent ionic solutions. Quantitative SECM image analysis demo nstrated that 40% to 60% of the total Fe(CN)(6)(-4) flux occurred thro ugh appendages in the skin, SECM analysis of skin samples exposed to a known transport enhancer, sodium dodecylsulfate, indicated that the i ncrease in the ion transport rate occurred exclusively in nonporous sk in tissue.