Dennal and transdermal delivery of an anti-psoriatic agent via ethanolic liposomes

The aim of the current investigation is to evaluate the transdermal potential of novel vesicular carrier, ethosomes, bearing methotrexate (MTX), an anti-psoriatic, anti-neoplastic, highly hydrosoluble agent having limited transdermal permeation. MTX loaded ethosomes were prepared, optimized and characterized for vesicular shape and surface morphology, vesicular size, entrapment efficiency, stability, in vitro human skin permeation and vesicle-skin interaction. The formulation (EE9) having 3% phospholipid content and 45% ethanol showing the greatest entrapment (68.71 +/- 1.4%) and optimal nanometric size range (143 +/- 16 nm) was selected for further transdermal permeation studies. Stability profile of prepared system assessed for 120 days revealed very low aggregation and growth in vesicular size (8.8 +/- 1.2%). MTX loaded ethosomal carriers also provided an enhanced transdermal flux of 57.2 +/- 4.34 mu g/cm(2)/h and decreased lag time of 0.9 h across human cadaver skin. Skin permeation profile of the developed formulation further assessed by confocal laser scanning microscopy (CLSM) revealed an enhanced permeation of Rhodamine Red (RR) loaded formulations to the deeper layers of the skin (170 pm). Also, the formulation retained its penetration power after storage. Vesicle skin interaction study also highlighted the penetration enhancing effect of ethosomes with some visual penetration pathways and corneocytes swelling, a measure of retentive nature of formulation. Our results suggests that ethosomes are an efficient carrier for dermal and transdermal delivery of MTX. (C) 2007 Elsevier B.V. All rights reserved.