Novel Approaches for Brain Drug Delivery System-Review
The brain is a delicate organ, and nature has very efficiently protected it. Drug delivery into the brain was difficult due to the existence of blood brain barrier, which only permits some molecules to pass through freely. The brain is shielded against potentially toxic substances by the presence of two barrier systems: the blood brain barrier (BBB) and the blood cerebrospinal fluid barrier (BCSFB). Unfortunately, the same mechanisms that protect it against intrusive chemicals can also frustrate therapeutic interventions. In past decades, nanotechnology has enabled much technical advancement, including drug delivery into the brain with high efficiency and accuracy. The challenging domain of effective brain delivery has led to a keen scientific pursuit and as a result many novel methods have been invented and patented. In the present paper, we summarize recent important advancements in employing nanotechnology for drug delivery. The technological strategies are essentially non-invasive methods of drug delivery to malignancies of the central nervous system (CNS) and are based on the use of nanosystems (colloidal carriers) such as liposomes, polymeric nanoparticles, solid lipid nanoparticles, polymeric micelles and dendrimer. Based on the current findings, it can be concluded that crossing of the BBB and drug delivery to CNS is extremely complex and require a multidisciplinary approach such as a close collaboration and common efforts among researchers of several scientific areas, particularly medicinal chemists, biologists and pharmaceutical technologists.