Transdermal insulin delivery using lipid enhanced electroporation.

Area of Science:

• Biomedical Engineering
• Dermatology
• Pharmacology

Background:

• Anionic lipids enhance electroporative transport of molecules up to 10 kDa.
• Phospholipid charge, not head group type, influences transdermal transport.
• Saturated acyl chains in phospholipids improve transport of larger molecules.

Purpose of the Study:

• To investigate the effect of 1,2-dimyristoyl-3-phosphatidylserine (DMPS) on transdermal insulin transport via electroporation.
• To quantify insulin transport enhancement using porcine epidermis as a model.
• To elucidate the pathways of insulin transport through the epidermis.

Main Methods:

• Utilized porcine epidermis in a glass vertical diffusion apparatus.
• Applied negative electrical pulses across the epidermis using platinum electrodes.
• Measured fluorescein-labeled insulin transport in the presence and absence of DMPS.

Main Results:

• Electroporation with DMPS resulted in over a 20-fold enhancement of insulin transport.
• Nearly all transported insulin reached the receiver compartment with DMPS, unlike controls.
• Fluorescence microscopy indicated transport primarily through lipid-rich regions surrounding corneocytes.

Conclusions:

• DMPS significantly enhances transdermal insulin delivery via electroporation.
• Electroporation in the presence of anionic lipids improves the efficiency of insulin transport across the skin.
• Insulin transport predominantly occurs through intercellular lipid pathways in the stratum corneum.