Chitosan nanoparticles for nasal drug delivery

The nasal route is commonly used for local drug delivery. However, researchers are currently exploring this route for systemic and central nervous system (CNS) drug delivery due to its safety and convenience, as well as its direct and rapid access to the brain. Chitosan (CS) is a natural biodegradable polymer known for its biocompatibility, permeability enhancement, mucosal retention, safety, and non-toxic properties. CS and its derivatives are highly desirable polymers used in nasal delivery as they limit mucociliary clearance by enhancing nasal retention of formulations. Advancements in nanotechnology have led to the design of various CS-based nanoparticles (NPs) to enhance nasal drug delivery. This review covers recent research on novel CS-based NPs explored in the nasal delivery of small molecule drugs and macromolecules for local, systemic and CNS effects. It also highlights some common targeting ligands and polymer coatings used in the surface modification of CS NPs. Finally, the review covers some of the current challenges limiting the translation of preclinical studies to commercial nasal products.