Enhanced transdermal delivery with fatty acids and electroporation

Abstract

The first part of thesis dealt with understanding of enhancement mechanisms of fatty acids in solvents with different polarity, using physostigmine as model drug. Fatty acids showed greater enhancement capabilities in hydrophilic solvents such as propylene glycol (PG) as physostigmine permeation was greater in PG-based formulations than mineral oil-based formulations. Next, skin permeability post electroporation was investigated with physostigmine as a model drug. Despite the lack of electrophoretic drug transfer across skin, physostigmine permeation across skin post electroporation increased. Synergy of oleic acid-based formulation and electroporation improved physostigmine permeation further. The second part of thesis utilised the synergy between chemicals and electroporation to deliver larger molecules like cyclosporin A (CsA) and lutenising hormone releasing hormone analog ([D-Ala6]-LHRH). Higher permeation was achieved for both peptides compared with passive permeation. Synergy between fatty acids and electroporation was effective in increasing [D-Ala6]-LHRH permeation across the skin and it was quite comparable to that obtained with iontophoresis as reported in literature.