Preparation and evaluation of transferosomes loaded with antiwrinkle agents

The degeneration of extracellular matrix and higher pH of wrinkled skin logically require matrix metalloproteinase inhibitor, eg, ethylenediaminetetraacetic acid (EDTA) and formulation pH of around 5.5. Alpha-hydroxy acid, eg, glycolic acid improves photodamaged skin. Vitamin E (α-tocopherol) is an antioxidant protectant of skin membrane. For carrying these multiple antiwrinkle agents deeper into the skin, deformable lipid vesicle, transferosome, seems to be a good choice as, at the same time, they have the capability to load both water- and lipid-soluble agents and to penetrate through tiny skin pore. Hydrogenated phosphatidylcholine and Tween 80 were used to prepare transferosome by thin-film method. Liposome was prepared in the same way except Tween 80 was replaced by cholesterol. Vitamin E (α-tocopherol), glycolic acid and EDTA were loaded into both transferosome and liposome during their preparation. Phosphate buffered saline (PBS, pH 5.5) was used during hydration of lipid films. The average sizes of transferosome and liposomes were 50 and 177 nm, respectively. Their polydispersity indexes, 0.244 and 0.374, respectively, showed that they were homogenous in sizes in each class. As was expected their zeta-potentials were negligible, namely, 0.9 to 1.0 mV. As measured by a validated UV-VIS spectrophotometric method, the vitamin E loading efficiency of transferosome, 96.66 %, was better than that of liposome, 86.71 % with a vitamin E to lipid ratio of 3.41 and 3.05 mM per 100 mM lipid, respectively. Finally, the lipid vesicles were incorporated separately into Carbopol Ultrez 21 and Carbopol 934 gels with a final concentration of vitamin E, glycolic acid and EDTA in gels being 0.005, 1 and 0.1 % (w/w), respectively, and a pH of 5.0 – 6.2. Rheograms of all the four gel formulations showed a plastic behavior with a yield value. The plastic viscosities of these gels were 1.9925 & 1.9692 cP for transferosome and liposome in Carbopol Ultrez 21 and 0.5368 & 0.5851 cP in Carbopol 934. There was no effect of vesicle types on gel viscosity. To conclude that transferosome loading several antiwrinkle agents is a suitable candidate for evaluation for in vivo efficacy.