Mucoadhesive and enzymatic inhibitory nanoparticles for transnasal insulin delivery

To develop a novel nanocarrier with mucoadhesion and enzymatic inhibition for transnasal insulin delivery. METHODS & METHODS: The physicochemical characterization of the nanoparticles included size and morphology, as well as mucoadhesion and enzymatic inhibition. The in vitro release of insulin from the nanoparticles was evaluated in 3 mg/ml glucose medium. The cytocompatibility of the nanoparticles was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The interactions of the nanoparticles with Caco-2 cells and nasal epithelia, and the effect of the nanoparticles on transnasal insulin delivery were estimated.

The nanoparticles were spherical in shape, with an average size of 100 nm, and presented strong enzymatic inhibitory activity and high mucin adsorption ability. The insulinloaded nanoparticles showed the rapid insulin release in 3 mg/ml glucose medium. The nanoparticles were noncytotoxic to Caco-2 cells. Furthermore, the insulin-loaded nanoparticles overcame mucosal barriers and significantly decreased plasma glucose levels.