The use of nanotechnologies to develop nanocarriers for oral insulin delivery is one of the strategies that has received significant attention. The basis for this development has been that nanocarriers can protect the peptides against the harsh gastric environment including enzymatic degradation, while controlling drug release and increasing their absorption in the small intestine. With a higher surface-to-volume ratio than that of conventional drug systems, nanocarriers can significantly increase their cellular contact with the intestinal epithelium, thereby offering more chances for the drug to get across this epithelium. The main aim of this work was to elucidate the potential of protamine nanocapsules as an effective oral drug delivery system for insulin (and other similar peptides). Nanocapsules consisting of an oily core and polymeric shell will be developed and characterized. Their stability in different simulated intestinal media with and without enzymes will be studied including their capacity to protect the loaded peptide from enzymatic degradation. Their toxicity and transport across Caco-2 cells will also be elucidated and thereafter their in vivo efficacy will be determined in rats
