IN- VITRO FORMULATION AND EVALUATION OF TOLBUTAMIDE LIPOSOME

The present investigation deals with liposomes. Liposomes are effective in extending the duration of action for days or months. In the present study liposomal formulations containing Tolbutamide were prepared and studied. Because of its shorter plasma half-life (t1/2=1.5 h) frequent administration by the patient is necessary to maintain steady state plasma concentration. Designing of controlled release formulation is necessary to maintain steady state plasma concentration for longer period of time and to reduce the frequency of administration. So, an attempt was made to formulate liposomal suspensions containing Tolbutamide to sustain its action. Liposomal formulations were evaluated for drug entrapment, surface characterization, in-vitro drug release studies, release kinetics and its mechanisms. Liposomal suspensions were prepared using film hydration technique using varying concentrations of phosphatidylcholine and cholesterol and optimize the ideal combination for required drug release. The prepared liposomes were rigid, intact and fulfilled all official requirements. The results of in vitro drug release studies showed that release from liposomal formulation was slow and sustained for > 12 hrs period. The formulations followed first order kinetics and release mechanism was non-fickian diffusion from all the formulations. Thus the liposomal suspensions of Tolbutamide were successfully developed.