Physico-Chemical Characterization and Initial Evaluation of Carboxymethyl Chitosan–Hyaluronan Hydrocolloid Systems with Insulin Intended for Intranasal Administration

The nasal route of administration can bypass the blood-brain barrier in order to obtain a higher concentration in the brain, thus offering a feasible alternative route of administration for diseases associated with the central nervous system. The advantages of the intranasal administration and the potential favorable therapeutic effects of intranasally administered insulin led to the formulation of carboxymethyl chitosan (CMC) and sodium hyaluronate (NaHA) hydrocolloidal systems with insulin for nasal administration, targeting nose-to-brain delivery and the initial assessment of these systems. The influence of the formulation variables on the response parameters defined as surface properties, rheology, and in vitro release of insulin were analyzed using experimental design and statistical programs (Modde and Minitab software). The systems recorded good wetting and adhesion capacity, allowing the spread of the hydrocolloidal systems on the nasal mucosa. The samples had a pseudoplastic flow and the rapid release of the insulin was according to our objective. According to the physico-chemical characterization and preliminary assessment, these formulations are appropriate for administration on the nasal mucosa, but further studies are necessary to demonstrate the beneficial therapeutic actions and the safety of using intranasal insulin.