Chapter 19 - Colloidal drug delivery system for brain-targeting therapy

Abstract

Targeting delivery of drug and gene to the brain for treating diseases in the central nervous system (CNS) is a thorny issue nowadays. Owing to brain’s inherent traits, the blood–brain barrier (BBB) protects the CNS and commonly prevents antibiotics, peptides, nucleic acids, and anticancer agents from entering the brain. The use of colloidal delivery systems, such as nanoparticles, liposomes, micelles, and dendritic biopolymers, has drawn a particular attention in the therapy for brain pathology. The colloidal carriers can also be manipulated to guide the drugs toward desired cells and improve the biodistribution. In addition, the formulation and physicochemical properties of particles play an important role in bioavailability and targeting efficiency of drug and gene. One of the most crucial benefits of colloidal delivery systems for treating brain diseases is that they can overcome the following multiple physiological obstacles: intracellular uptake, BBB penetration, targeted accumulation, escape from endosomal entrapment, and escape from reticuloendothelial clearance. In this review, we particularly overview colloidal drug delivery systems, focusing on the effect of particle size and shape, surface charge, and surface modification with targeting moiety on delivering drugs across the BBB and against brain-related disorders, including acute ischaemic stroke, brain tumour, Alzheimer’s disease, and Parkinson’s disease.