Development, Characterization and Ex vivo Evaluation of Various Liposome-encapsulated Aceclofenac Formulations

Aim: Formulation of aceclofenac (ACE) into liposomal gel, improving its skin permeation and potentiate its local anti-inflammatory effect. Methodology: ACE liposomes were fabricated by lipid film hydration technique. The prepared formulations were traditional liposomes containing cholesterol (F1), ultra-deformable liposomes containing Tween 60 (F2) and modified liposomes containing both cholesterol and Tween 60 (F3). All formulations were incorporated in 1% carbopol 974 as gelling agent. The developed liposomal formulations were evaluated for its particle size, zeta potential, drug entrapment efficiency percent and stability for 90 days at 4'C. While the developed liposomal gel formulations were characterized for its in vitro ACE release and ex vivo permeation through rat skin. Anti-inflammatory effect of ACE gel formulations were evaluated in rats using carrageenan induced paw edema. Results: The prepared liposomes had a mean vesicle size of 577 nm, 218 nm and 332 nm for F1, F2 and F3 respectively and entrapment efficiency percent of 76.8%, 58.3% and 66.2% for F1, F2 and F3 respectively. The stability study revealed that F1 vesicles have the highest physical stability followed by F3, while F2 showed the lowest stability in terms of vesicles size and entrapment efficiency percent. The in vitro and ex vivo results showed higher drug release and permeability from F2 and F3 than that of F1. In addition, ACE liposomal formulations have significant higher antiinflammatory effect than that of marketed product Bristaflam cream (R). Conclusion: All liposomal gel formulations have the ability to enhance ACE anti-inflammatory effect in rats paw edema in comparison with marketed product Bristaflam cream (R).