An extensive analysis of oral insulin: Application for oral insulin delivery

The development of dependable and effective oral insulin delivery systems has long been a challenge for pharmaceutical researchers because of several obstacles, such as mucus barriers, enzyme breakdown, and stomach acidity. However, a number of tactics were created to encourage membrane permeability and biological activity while preventing insulin breakdown in the gastrointestinal tract (GIT). The potential of chitosan polymer-based carriers to preserve insulin in the alimentary canal and efficiently transport it through the intestinal mucosa, hence increasing its bioavailability, has led to extensive research on these tactics. Chemical and physical changes have been made to chitosan to improve its capabilities, and recently, chitosan beads, microparticles, and nanoparticles have shown promise as oral insulin delivery (OID) systems. An overview of the many forms of diabetes mellitus, insulin production, and gastrointestinal obstacles to oral insulin is made easier by this article. Also covered are the drawbacks of subcutaneous insulin delivery as well as alternative administration methods. The difficulties of safely delivering insulin through the GIT and methods to increase its bioavailability are emphasized, as the GIT is the best and most practical oral administration route. This analysis also emphasizes the latest developments in chitosan-based OID carriers and their possible uses in the future.