Original Articles
K Latha, P Lalitha and SK Nass
Abstract
The main objective of this study was to formulate and evaluate darifenacin hydrobromide loaded nano-liposomes for prolonged drug release. Drug and excipient compatibility study was performed by FTIR and the study revealed that there was no interaction between drug and excipients. Various formulations were prepared by conventional thin film hydration method using different phospholipids such as phospholipon 80H, phospholipon 90H and soyalecithin. The ratio of phospholipid to cholesterol was optimized as 3:1 and used for phospholipid further studies. All formulations were evaluated for entrapment efficiency and in vitro drug release studies. The optimized formulation with soyalecithin DLSL6 showed highest entrapment efficiency (78.5%) and highest drug release in 24 hrs (82%). The optimized formulation was evaluated for FTIR, SEM, and particle size analysis and zeta potential studies. The FTIR study revealed that there was no interaction between drug and excipients. The vesicles were smooth surfaced with uniform distribution which is evident from surface morphology analysis from SEM. The optimized formulation was found to be stable with zeta potential value of -51.6 mV and the average particle size of 24.1 nm with uniform distribution. The regression coefficient (R2 value) 0.981 indicating release as zero order, where “n” value 0.455 states the mechanism as fickian diffusion. The optimized formulation was subjected to stability studies at room temperature and 4ºC for two months and liposomes were found to be stable with no significant change in the entrapment efficiency.