Nanoparticle systems for nose-to-brain delivery

Abstract Intranasal administration can bypass blood-brain barrier and rapidly deliver drugs from the nasal mucosa to the brain in a noninvasive way for the treatment of central nervous system disorders. However, because of the poor capacity of penetration through nasal mucosa, the enzymatic degradation, and the rapid mucociliary clearance, the quantities of drugs, especially hydrophilic drugs, transported directly from nose to brain are normally less than 0.1%–1%. The encapsulation of drugs into nanometer-sized particles has been shown to overcome these problems and improve the nose-to-brain drug delivery. This chapter introduces the anatomy features of nasal cavity, the pathways involved in the direct nose-to-brain transport of drugs such as the olfactory nerve pathways, trigeminal nerve pathways and cerebrospinal fluid pathways, and reviews the recent development of nanotechnologies and nanoparticles used in the nose-to-brain drug delivery. Several nano-sized systems including chitosan-based nanoparticles, polyester-based nanoparticles, solid lipid nanoparticles, liposomes, nanoemulsions, micelles, and nanocomplexes exhibit significant advantages in enhancement of brain delivery of intranasally administrated drugs. The challenges and future prospective of these nano-sized systems are also discussed.