Excipients for efficient skin penetration

Three main steps govern drug diffusion from the formulation to the skin:

• Solubility: the formulation must solubilize a sufficient amount of drug to reach the effective concentration at the target site
• Partition: the drug must partition out of the delivery vehicle into the upper layers of the SC
• Diffusion: the drug molecule diffuses through the SC mainly via the intercellular path

Discover Gattefossé range of excipients for solubilization and skin penetration:

• Labrasol^®: reversibly opens tight junctions/desmosomes
• Plurol^® Oleique CC 497 enables drug penetration with modification of the lipid domain of the skin
• Transcutol^® P: enables skin penetration with no effect on skin lamellar structure
• Capryol^® PGMC and Lauroglycol™ FCC: fatty acid esters of propylene glycol enhance skin penetration

 Evaluating skin permeation with in vitro release test (IVRT) and in vitro permeation test (IVPT)

In vitro methods exist to assess the drug penetration through the skin: IVRT uses synthetic membranes while IVPT uses animal or human skin.

Rigorous protocols need to be developed to ensure the reliability of the results. Detailed information is given in our joint webinar with Teledyne Hanson provider of Franz cells. Gattefossé has developed standard protocols to evaluate skin penetration properties of our excipients in formulations. Access our publications for more details or contact us.