Formulation and in vitro evaluation of vincristine encapsulated niosomes

Vesicles containing vincristine were prepared using different nonionic surfactants and by employing different techniques. The entrapment efficiency and the stability in terms of drug leakage of the noisomes prepared by different methods were compared. Transmembrane pH gradient (inside acidic) drug uptake process (TMpH) was proved to be most satisfactory yielding 90% drug entrapment when span 40-cholesterol (1:1) were used as vesicle forming agents. A relatively slow release pattern of the entrapped vincristine from the niosomes prepared by this method indicates an enhanced stability of the system.