Nanocarrier facilitated drug delivery to the brain through intranasal route: A promising approach to transcend bio-obstacles and alleviate neurodegenerative conditions

Advancements in neurosciences lead to the development of potential therapeutics that are capable of altering pathophysiology and mitigate neurological disorders but are inefficient due to the impediment of biological barriers. Over past decades nanocarrier systems have been extensively studied for their potentials for targeting the brain. Similarly intranasal drug delivery systems are studied for improved permeation of therapeutics across the blood-brain barrier (BBB). Nanoformulation systems have exhibited promising results for precise delivery to brain surpassing all hindrances like chemical and biological barriers besides competently tackling efflux transporters and deliver therapeutic concentrations in brain tissues. Our review focuses briefly on the pathways and mechanisms accountable for drug absorption from nasal mucosa, factors responsible for the nasal delivery and strategies to surpass barriers. Similarly we highlighted various challenges faced by the carrier systems in targeting central nervous system (CNS), correspondingly this review also underlines the advancements in green nanotechnology for developing nanoparticles as an alternative for conventional approaches for development of nanocarriers. Similarly over the years intelligent polymers in nanosystems for effective drug delivery is subsequently highlighted. Patented technologies are also emphasized on recent research trends pertaining to intra-nasal (IN) nanocarrier system with the importance of safety and neurotoxicity of numerous carrier systems.