Nanosphere based oral insulin delivery

Zinc insulin is successfully encapsulated in various polyester and polyanhy dride nanosphere formulations using Phase Inversion Nanoencapsulation (PIN) . The encapsulated insulin maintains its: biological activity and is releas ed from the nanospheres over a span of approximately 6 h. A specific formul ation, 1.6% zinc insulin in poly(lactide-co-glycolide) (PLGA) with fumaric anhydride oligimer and iron oxide additives has been shown to be active ora lly. This formulation is shown to have 11.4% of the efficacy of intraperito neally delivered zinc insulin and is able to control plasma glucose levels when faced with a simultaneously administered glucose challenge. A number o f properties of this formulation, including size, release kinetics, bioadhe siveness and ability to traverse the gastrointestinal epithelium, are likel y to contribute to its oral efficacy. (C) 2000 Published by Elsevier Scienc e B.V. All rights reserved.