Drug Targeting to the Brain - A Review

In last few years, scientists have been constantly engaged in the research to develop an effective drug delivery system to the brain. The blood brain barrier (BBB) is a formidable obstacle for a large number of drugs. As a consequence, it prevents effective treatment of many severe and life threatening diseases associated with brain. The BBB is a tight junction of brain capillary endothelial cells (BCECs), that abolishes aqueous paracellular pathway across the cerebral endothelium and it is also a rate-limiting factor in determining permeation of a drug into brain. Many attempts have been envisaged to overcome the BBB following drug transport. The most commonly used attempts are chemical modification of drug molecule or transient opening of BBB by osmotic methods. But none of these methods decisively proved their potential in drug delivery to brain. Other alternative strategies are to use carrier systems, e.g. liposomes, polymeric nanoparticles, solid lipid nanoparticles, colloidosomes, dendrimers, to delivery drug to brain.