Liposomal Drug Delivery of Metronidazole for the Local Treatment of Vaginitis

The present investigation was aimed to formulate liposomes containing metronidazole for local therapy of vaginitis, capable to efficiently deliver entrapped drug during an extended period of time. Liposomes were prepared by simple thin film hydration technique using soya lecithin and cholesterol. Some preliminary trials and 3 factorial design were conducted to optimize the formulation. The drug to Soya lecithin to cholesterol ratio and volume of hydration media were chosen as independent variables. The percentage drug entrapment, particle size and drug release at 12 h were chosen as dependent variables. To achieve application viscosity and further improve the stability of liposomes, the prepared liposomes were incorporated in the bioadhasive carbopol 934P gel (1%), and the system were evaluated for the in vitro drug release and drug stability in phosphate-buffer pH 4.5 and simulated vaginal fluid (VFS) at 37±1C. Stability study for liposome suspension and liposomal gel were carried out. All the performed experiments confirm the applicability of liposomes as a novel drug carrier system for the local treatment of bacterial vaginosis.