A stable multiple emulsion system bearing isoniazid: preparation and characterization.

Multiple emulsions with an oily liquid membrane (w/o/w) bearing isoniazid were prepared by an improved 2 x 2 step emulsification technique. Both of the interfaces of the liquid membrane were stabilized by using microcrystalline cellulose (MCC) in external as well as internal aqueous phases. The emulsions were characterized for droplet size, percent formation of multiple emulsion, release rate effect of Tween-80 in external phase, phase volume ratio on release, and stability during aging at various storage conditions. The droplet size was small and yield of multiple emulsion was fairly good. The increasing concentration of MCC in either internal or external phase increased the droplet size. The system holds promise in tuberculosis therapy.