Transdermal delivery from a lipid sponge phase—iontophoretic and passive transport in vitro of 5-aminolevulinic acid and its methyl ester
Artikel i vetenskaplig tidskrift, 2004

The hydrochloride salts of 5-aminolevulinic acid (ALA) and its methyl ester (m-ALA), respectively, were dissolved in a lipid sponge phase comprising monoolein, propylene glycol and aqueous buffer at concentrations of approximately 0.25% and 16% w/w m-ALA. The iontophoretic and passive delivery of ALA and m-ALA from this formulation through porcine skin in vitro were measured and compared to formulations used in clinical practice, 20% w/w ALA in Unguentum M and Metvix(R) (a cream containing 16% w/w m-ALA). A sponge phase with 16% w/w m-ALA showed a higher passive flux (approximately 140 nmol cm(-2) h(-1) at 5 h) but a lower iontophoretic flux (approximately 800 nmol cm(-2) h(-1) at 5 h) compared to the clinically used products but the differences are hardly significant due to large standard deviations. ALA and m-ALA in sponge phase formulation showed iontophoretic fluxes in the range 80-100 nmol cm(-2) h(-1) at 3 h, i.e. values comparable to the passive fluxes from the more concentrated vehicles. The results demonstrate that the lipid sponge phase, a thermodynamically stable liquid with amphiphilic character, may have potential as a transdermal drug delivery vehicle.

Transdermal delivery

Iontophoresis

delta-Aminolevulinic acid methyl ester

Monoolein

Sponge phase

Författare

Nadia Merclin

Uppsala Biomedicinska Centrum

Johanna Bender

Chalmers, Institutionen för material- och ytkemi, Teknisk ytkemi

Emma Sparr

Lunds Universitet

Richard Guy

Universite de Geneve

Hans Ehrsson

Karolinska University Hospital

Sven Engström

Chalmers, Institutionen för material- och ytkemi, Teknisk ytkemi

Journal of Controlled Release

0168-3659 (ISSN)

Vol. 100 191-198

Ämneskategorier

Farmaceutisk vetenskap

DOI

10.1016/j.jconrel.2004.08.025