Skin permeation enhancement of ascorbyl palmitate by liposomal hydrogel (lipogel) formulation and electrical assistance.

To enhance skin permeation of ascorbyl palmitate (AsP), it was encapsulated in liposomes, and formulated into liposomal hydrogel (lipogel) by dispersing the liposome into poloxamer hydrogel matrix. To improve the skin permeation of AsP, we applied electric current supplying system that mimics an electric skin massager. We evaluated the effects of composition and surface charge of the liposomes and electrical assistance on the skin permeation of AsP. In the passive transport study, the permeated amounts of AsP from all the lipogels tested were higher than that of control hydrogel which contains Transcutol used to solubilize AsP. In the cathodal delivery condition with a fixed cathodal current of 0.4 mA/cm2, the skin permeation characteristics of the negative lipogels were superior to that obtained with the neutral lipogels and the drug permeation was more increased with increased surface negative charge of the liposomes. In conclusion, the lipogel system was thought as a helpful drug delivery system to enhance skin permeation of AsP. Combined use of negative lipogel with cathodal electric assistance was found to be promising in enhancing the skin delivery of AsP.