Preparation and characterization of insulin nanoparticles using chitosan and Arabic gum with ionic gelation method

In the past decade, many strategies have been developed to enhance oral protein delivery. The aim of the current work was to develop a nanoparticulate system based on ionic gelation between chitosan and Arabic gum for loading of insulin. Various formulations were prepared using 23 factorial designs. The optimum association efficiency was obtained for formulations F2, F5, and F8. The release profile of insulin in phosphate buffer solutions (pH 6.5 and pH 7.2) is completely different than that in acidic medium (pH 1.2). Increased solubility of chitosan in acidic medium and better swelling of Arabic gum chains at pH >6.5 resulted in lower insulin release of nanoparticles at pH 6.5 in comparison with that of the other pH mediums. The values of the exponent n were 0.49 and 0.82 for formulations F8 and F5, respectively, indicating a non-Fickian transport. This suggests that release is possibly controlled by diffusion or relaxation of the polymer chains. From the Clinical Editor: This paper summarizes the development of a nanoparticulate system based on ionic gelation between chitosan and gum Arabic for oral delivery of insulin. If preclinical studies in animal models will indicate reliable and quantifiable delivery of insulin, this method may pave the way to a novel and less invasive way of administering insulin to diabetes patients. (C) 2010 Elsevier Inc. All rights reserved.