The Nasal Route Redefined: The Impact of Chitosan Nanoparticles on Drug Delivery

The nasal route presents a viable alternative for medication administration, circumventing first-pass metabolism and improving bioavailability, especially for neurological conditions. Nonetheless, obstacles such as mucociliary clearance and enzymatic degradation constrain its effectiveness. Chitosan nanoparticles (CS-NPs) have emerged as a viable option due to their mucoadhesive properties, biocompatibility, and capacity to modulate tight junctions, thereby enabling direct nose-to-brain administration.

This review explores various methods for the production of chitosan nanoparticles (CSNPs), their characterization techniques, drug delivery applications via the nasal route, and an examination of related patents. Search engines such as PubMed, Google Scholar, and ScienceDirect were utilized for the literature search. Studies published between 2015 and 2025 were included.

The use of CS-NPs in the delivery of various treatments, including anticancer, antiparkinsonian, antianxiety, and antischizophrenic medications, shows great promise. Research has demonstrated that certain formulations, such as chitosan-PEG nanovesicles and transferrin-conjugated nanoparticles, exhibit improved bioavailability, sustained release, and enhanced brain targeting. Patents have further supported the development of mucoadhesive and combinatorial therapies.

While there are notable benefits, obstacles such as rapid mucociliary clearance, limited drug-loading capacity, and variability in nasal responses persist. Proposed solutions to address these challenges include innovations like mucoadhesive coatings, hybrid polymers, and stimuli-responsive systems. Utilizing computational modeling and conducting clinical trials are crucial for improving formulations.

CS-NPs represent a transformative approach to nasal medication delivery. To fully realize their potential, future research should focus on advanced formulations and personalized delivery systems, thereby facilitating clinical translation and improving therapeutic outcomes.