Freeze-dried chitosan/pectin nasal inserts for antipsychotic drug delivery

The objective of this investigation was the development of chitosan/pectin based nasal inserts to improve bioavailability of antipsychotic drugs in the treatment of psychotic symptoms. In fact, the nasal route of administration ensures systemic availability avoiding the first-pass metabolism and obtaining more efficacious treatments. Chitosan/pectin polyelectrolyte complexes were prepared at pH 5.0 with different polycation/polyanion molar ratios and lyophilized in small inserts in the presence of chlorpromazine hydrochloride. The results show that higher amount of pectin in the complexes, with respect to higher amount of chitosan, produced a more evident porous structure of the nasal inserts, improving water uptake ability and mucoadhesion capacity. Finally, the presence of increasing amounts of pectin allowed the interaction with chlorpromazine hydrochloride inducing the formation of less hydratable inserts thus limiting drug release and permeation. This investigation verifies the formation of polyelectrolyte complexes between chitosan and pectin at pH values in the vicinity of the pKa interval of the two polymers and confirms the potential of these complexes, capable of achieving antipsychotic drug delivery in the nasal cavity.