Nanoparticle-mediated brain-specific drug delivery, imaging, and diagnosis

Abstract

Central nervous system (CNS) diseases represent the largest and fastest-growing area of unmet medical need. Nanotechnology plays a unique instrumental role in the revolutionary development of brain-specific drug delivery, imaging, and diagnosis. With the aid of nanoparticles of high specificity and multifunctionality, such as dendrimers and quantum dots, therapeutics, imaging agents, and diagnostic molecules can be delivered to the brain across the blood-brain barrier (BBB), enabling considerable progress in the understanding, diagnosis, and treatment of CNS diseases. Nanoparticles used in the CNS for drug delivery, imaging, and diagnosis are reviewed, as well as their administration routes, toxicity, and routes to cross the BBB. Future directions and major challenges are outlined.

Figure 1

Illustration of typical nanoparticles used in brain-specific drug delivery, imaging, and diagnosis.

Figure 2

The main routes for transport of substances across the BBB. a) paracellular aqueous pathway, b) transcellular lipophilic pathway, c) transport proteins, d) receptor-mediated transcytosis, and e) adsorptive-mediated transcytosis.