Abstract

The aim of this study was to encapsulate prostaglandin E1 (PGE1) in liposomes, to determine the transdermal flux characteristics in vitro and to evaluate the stability of prostaglandin E1 (PGE1) in these novel transdermal delivery systems. A sensitive, reversed-phase, isocratic high-performance liquid chromatography assay of PGE1 and its major degradation products in solution, liposomes, and other topical dosage forms was developed. The effect of formulation variables – vehicle type, drug concentration, drug/lipid ratio, apparent encapsulation efficiency and pH – on transdermal drug delivery was assessed using the in vitro flow-through diffusion cell technique. The steadystate transdermal flux from the various liposomal formulations ranged from 0.01 to 0.787 (µg/cm2/hour-1) depending on the composition. Compared to the optimum liposome formulation, a conventional nonliposomal PGE1 formulation yielded a steady-state flux of 0.04 µg/cm2/hour-1. Lipid content and the apparent encapsulation efficiency correlated positively with transdermal delivery of PGE1 from liposomes. The stabilization of PGE1 by liposomes depended on the lipid composition, pH of the formulation, and storage temperature but was independent of the drug concentration. It is proposed that a stable transdermal liposomal PGE1 product, which can deliver therapeutic amounts of PGE1 in vivo, may be feasible.

Related Keywords

• prostaglandin E1

Related Categories

• DERMATOLOGY
• HRT
• PEER-REVIEWED