Pelleted bioadhesive polymeric nanoparticles for buccal delivery of insulin: preparation and characterization.

The study was an attempt to develop an alternative buccal delivery system for insulin. Insulin bearing nanoparticles were prepared by the emulsion internal phase evaporation method. The effect of some formulation variables viz., polymer/drug ratio and emulsifier concentration was studied on particle size and entrapment efficiency. Nanoparticles were pelleted to impart three-dimensional structural conformity and coherence thereby facilitating buccal application. Solid lateral and horizontal sedimentaton in the pellet can be avoided by nanoparticulation and ensuring uniform drug distribution throughout the pellet. The in vitro studies of the pellets included bioadhesion and drug release profile. In vivo studies were performed on diabetic rats. A significant hypoglycemic response was observed after 7 h, without any detectable fluctuation in blood glucose profile and risk of hypoglycemia.