Pathways of ionic flow through human skin in vivo

Area of Science:

• Dermatology
• Bioengineering
• Electrophysiology

Background:

• Understanding electrical pathways in skin is crucial for drug delivery and device design.
• Stratum corneum is a primary barrier, but its role in ionic conduction is debated.

Purpose of the Study:

• To investigate the primary pathways of electric current through human skin.
• To clarify the role of stratum corneum and sweat ducts in electrical conduction.

Main Methods:

• Utilized specialized electrodes and measurement techniques.
• Analyzed electrical current flow across skin samples.

Main Results:

• Negligible current flow was observed through the stratified stratum corneum.
• Dominant ionic pathways were identified within the sweat duct units.
• Cellular orientation within sweat ducts may differ from the epidermis.

Conclusions:

• Sweat ducts are the principal routes for electrical current in the skin.
• The unique cellular orientation in sweat ducts may influence skin permeability studies.
• Findings impact the design and interpretation of transdermal drug delivery and bioelectrical measurements.