HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Enhanced delivery of 5-aminolevulinic acid esters by iontophoresis in vitro.

Abstract
The goals of this study were to quantitatively evaluate the iontophoretic delivery of a homologous series of cationic aminolevulinic acid (ALA) esters and to determine the contributions of electromigration and electroosmosis to their overall electrotransport in vitro. Anodal iontophoretic transport of ALA esters through porcine skin in vitro was followed for 2 h at a constant current of 0.5 mA/cm2. To deduce the mechanism, the concomitant transport of an electroosmotic marker, mannitol, was also assessed. Positively charged ALA esters of moderate lipophilicity showed increased iontophoretic flux through the skin. A more than 50-fold enhancement as compared with the zwitterionic parent ALA was observed for the methyl ester. As the size and lipophilicity of the ester increased, the efficiency of electrotransport decreased. The most lipophilic esters reduced the electroosmotic flow presumably because of the association of these cations with negative charges in the skin. Iontophoresis of methyl-ALA and hexyl-ALA also increased the amount of prodrug delivered into the skin. In summary, significant topical delivery of ALA esters can be achieved by iontophoresis, and transport into and across the skin was greatly enhanced compared with that of ALA itself. It remains to be seen whether this enhanced local bioavailability of the protoporphyrin prodrug can allow improved photodynamic therapy for the treatment of skin cancer.
AuthorsRenata F V Lopez, M Vitória L B Bentley, M Begoña Delgado-Charro, Denis Salomon, Hubert van den Bergh, Norbert Lange, Richard H Guy
JournalPhotochemistry and photobiology (Photochem Photobiol) Vol. 77 Issue 3 Pg. 304-8 (Mar 2003) ISSN: 0031-8655 [Print] United States
PMID12685659 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Prodrugs
  • Aminolevulinic Acid
Topics
  • Aminolevulinic Acid (administration & dosage, analogs & derivatives, pharmacokinetics)
  • Animals
  • In Vitro Techniques
  • Iontophoresis
  • Photobiology
  • Photochemotherapy
  • Prodrugs (administration & dosage, pharmacokinetics)
  • Skin (metabolism)
  • Sus scrofa

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: