Nanocarriers for Successful Drug Delivery Across Blood-Brain Barrier

The blood-brain barrier (BBB) is a unique anatomic structure at the interface between the central and peripheral nervous systems that is mainly constructed by tight junctions (TJ) and adherens junctions (AJ) [1]. The BBB becomes hyper-permeable to macromolecules during some brain pathologies such as brain tumors, stroke, Parkinson’s disease (PD), and Alzheimer’s disease (AD), resulting in a range of inflammatory responses and neuronal injuries [2]. However, the majority of currently available therapies are unable to reduce the main symptoms and improve the quality of life. Until now the research for effective treatments shows no significant improvement and drug delivery is a huge challenge that must be overcome. Among various strategies developed to overcome the BBB, a high attention has been centered for the fabrication of nanoscale drug carriers. Nanoparticles (NPs) are suggested as one of the most versatile platforms which can be regarded as the future of brain drug delivery. NPs possess the capacity to protect the loaded cargo while effectively transporting them into the targeted regions [3]. A wide variety of nanocarriers, such as polysaccharide, lipid, protein, polymeric, and inorganic NPs have been suggested to achieve neurological therapeutics with desired targeted and sustained release properties, mainly when their surface are modified with ligands or surfactants (Figure 1)[4] . C o r re s p o n d e n c e