Characterization and skin permeation of ketoprofen-loaded vesicular systems

Purpose: To determine the effect of elasticity on the skin permeation of ketoprofen from surfactant-based vesicular formulations and elastic liposomes. Methods: Ketoprofen-loaded surfactant-based vesicles and elastic liposomes were prepared by sonication. Citric buffer (at pH 3.0) was used as rehydration buffer. Characterization studies of the prepared liposomal formulations were performed by dynamic light scattering, extrusion, and H-1 and P-31, nuclear magnetic resonance (NMR) spectroscopy. Ketoprofen transport studies across human skin were performed for all formulations. Results: Stable ketoprofen-loaded formulations were prepared. Addition of an edge activator, in the absence of the drug, increased the elasticity of the vesicles and liposomes. Ketoprofen loading reduced the elasticity of the liposomes and surfactant-based-vesicles. However, at saturation, the elasticity was still higher than that in the absence of the edge activator and ketoprofen, except for ketoprofen-loaded liposomes with Span 80. NMR studies revealed that the ketoprofen molecules were entrapped in a vesicle bilayer in all vesicular formulations and that the ketoprofen molecules affected the phosphate mobility in the liposomal formulations. Ketoprofen transport studies across human skin clearly showed that the surfactant-based vesicular formulations were superior to the elastic liposomal formulations. Conclusion: Surfactant-based vesicles enhance ketoprofen transport across human skin, while no enhancement of ketoprofen was observed when loaded in elastic liposomes. (c) 2013 Elsevier B.V. All rights reserved.