VESICULAR NANOCARRIERS FOR NOSE-TO-BRAIN DELIVERY: COMPARATIVE INSIGHTS INTO LIPOSOMES, NIOSOMES, TRANSFERSOMES AND SPANLASTICS

Nose-to-brain drug delivery is a promising non-invasive approach for treating central nervous system disorders by bypassing the blood-brain barrier through olfactory and trigeminal pathways. However, mucociliary clearance, enzymatic degradation, and limited nasal residence time restrict its effectiveness. Vesicular nanocarriers, including liposomes, niosomes, transfersomes, and spanlastics, can enhance drug permeation, protect drugs from degradation, improve brain targeting, and provide sustained release. This review discusses nasal anatomy and physiology, brain-targeting mechanisms, and the structural and functional characteristics of these vesicular systems. Particular emphasis is given to elastic nanovesicles such as transfersomes and spanlastics due to their enhanced deformability and permeation. Current challenges and future prospects, including stability, scale-up, toxicity, regulatory considerations, surface modification, in situ gels, Quality by Design, and precision nanomedicine, are also highlighted.