Peroral insulin delivery using complexation gels

The goals of this work were to evaluate the in vitro and in situ efficacy of complexation hydrogels as oral drug delivery systems. Hydrogels of poly(methacrylic acid-graft-ethylene glycol) were prepared and loaded with insulin. In this study, we evaluated the effects of insulin loading on the in vitro release kinetics. In neutral media, the release rates of insulin from hydrogels increased with increasing drug loading. No insulin release occurred from any of the gels in acidic media. Additionally, we investigated the effects of particle size of insulin absorption from gels in the upper small intestine. Following administration of particles smaller than 100 μm to the ileum, significant reduction of the blood glucose levels were observed due to absorption of insulin from the complexation gels. These studies indicate the potential of these gels to serve as peroral insulin delivery systems.