Niosomes vs microemulsions: new carriers for topical delivery of Capsaicin.

The development of advanced biomaterials and drug-delivery systems has had a significant impact on our ability to treat several diseases. A new study was performed on niosomal formulations obtained from a mixture of commercial surfactants (Tween 80 and Span 80) to be applied topically for the release of Capsaicin. Capsaicin is the pungent principle of red pepper and it has a variety of pharmacological actions on the cardiovascular, respiratory and nervous systems. Niosomal carriers were prepared using a particular ratio between surfactants, to obtain systems with a specific HLB (10,12,14) and characterized in terms of dimension, morphology and their drug entrapment efficiency. Niosomes were compared to microemulsions prepared from the same surfactants in the same ratio, to evaluate their possible use in transdermal drug delivery. As regards the in vitro percutaneous permeation of Capsaicin from both microemulsions and niosomal formulations, it was carried out using diffusion Franz cells. The results indicate that niosomes could better promote the transdermal delivery of Capsaicin, with respect to microemulsions, even if both carriers could be an effective vehicle for topical delivery of this drug.