Optimization of transdermal delivery using magainin pore-forming peptide
Yeu-Chun Kim1, Peter J Ludovice, Mark R Prausnitz
1School of Chemical and Biomolecular Engineering Georgia Institute of Technology, Atlanta, GA 30332-0100.
The Journal of Physics and Chemistry of Solids
|July 13, 2010
Summary
Optimizing magainin peptide pretreatment enhances transdermal drug delivery by increasing skin permeability for small molecules. Higher concentrations and longer exposure times improved drug penetration, but larger molecules remained unaffected.
Area of Science:
- Pharmacology
- Biophysics
- Materials Science
Background:
- The stratum corneum's lipid bilayers present a significant barrier to transdermal drug delivery.
- Previous research demonstrated magainin peptide and N-lauroyl sarcosine (NLS) enhance skin permeability by disrupting lipid structure.
- Optimizing magainin formulation is crucial for improving transdermal permeation.
Purpose of the Study:
- To optimize pretreatment conditions (time and concentration) for magainin-enhanced skin permeability.
- To investigate the effect of magainin concentration and exposure duration on transdermal permeation.
- To determine the molecular size limitations for magainin-mediated skin penetration.
Main Methods:
- Formulation of magainin with N-lauroyl sarcosine (NLS) in 50% ethanol-in-PBS.
- Systematic variation of magainin pretreatment time and concentration.
- Measurement of transdermal permeation for fluorescein, calcein, and dextran.
Main Results:
- Skin permeability increased with longer magainin pretreatment times.
- Optimal magainin concentration for enhanced permeability was found to be 1 mM; higher concentrations (2 mM) reduced efficacy.
- Significant enhancement (up to 35-fold) in skin permeability was observed for fluorescein (323 Da).
- No enhancement in permeability was observed for larger molecules like calcein (623 Da) and dextran (3,000 Da).
Conclusions:
- Magainin pretreatment time and concentration significantly influence transdermal drug delivery.
- The magainin/NLS formulation effectively enhances skin permeability for small molecules up to approximately 323 Da.
- This optimized approach shows potential for targeted transdermal delivery of specific small-molecule drugs.
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