Preparation of tiny biodegradable capsules using electrocapillary emulsification

Conditions for preparing tiny biodegradable capsules were examined using electrocapillary emulsification that allows one to prepare monodisperse emulsions with ease by applying a DC potential between oil and water phases without mechanical agitation. The results obtained showed that a 1 : 4 mixture of polysorbate 80 (TO-10), a hydrophilic non-ionic surfactant, and sorbitan monooleate (SO-10), an oleophilic surfactant, is appropriate as the surfactant to be added to oil phase, cyclohexane is acceptable as the oil phase and 1000 V is optimum as the DC potential to be applied. The capsules prepared had sizes ranging from 100-300 nm and a surface roughness of ∼10 nm and degraded in model intestinal juice more easily and rapidly than in model gastric juice. In addition, the capsules containing lactoferrin, an anti-carcinogenic protein, were found to keep 12.5% of the protein used in encapsulation without losing its activity.