Nanobiotechnology-Based Drug Delivery to the Central Nervous System

Abstract

Background: Drug delivery across the blood-brain barrier (BBB) is a major limitation in the treatment of central nervous system (CNS) disorders. Several approaches are being investigated to improve drug delivery across the BBB. Objective/Methods: This review deals with the role of nanobiotechnology in CNS drug delivery. The small size of the nanoparticles enables them to penetrate the BBB and facilitate the delivery of drugs across the barrier. Several mechanisms are involved in this process and various strategies are used based on different types of nanomaterial and combinations with therapeutic agents. Examples are given of the use of liposomes and polymeric nanoparticles. Results: Nanoparticles can be used as nonviral vectors for CNS gene therapy. Although the use of nanotechnology is expected to reduce the need for invasive procedures for delivery of therapeutics to the CNS, some devices such as implanted catheters and reservoirs will still be needed. Nanomaterials can improve the safety and efficacy of such devices. Nano-engineered probes can deliver drugs at the cellular level using nanofluidic channels. There is some concern about the safety of nanoparticle entry in the brain and this needs to be resolved before human use. Conclusion: Although there is no approved nanotechnology-based CNS drug as yet that incorporates nanobiotechnology, the future for such developments is promising.

Theranostic liposomes loaded with quantum dots and apomorphine for brain targeting and bioimaging

“…However, internalization of receptors and their ligands by clathrin-coated pits corresponds to receptormediated transcytosis. 35 It could occur with theranostic liposomes since polyethylene glycol is recognized by lowdensity lipoprotein receptors on brain endothelial cells 36 Caveolae are invaginations on the cell membrane which are coated with caveolin. Filipin can inhibit liposomal uptake, suggesting the potential transport by caveolar pathways.…”

Occupational medicine implications of engineered nanoscale particulate matter

“…This is intriguing in light of the lung deposition model proposed by the International Council on Radiation Protection that shows nanoparticles less than 10 nm in aerodynamic diameter will preferentially deposit in the head airways region rather than the alveolar space [89][90][91] .…”

Nanotechnology-based drug delivery systems for the treatment of Alzheimer’s disease

“…[155][156][157] Drug delivery across the BBB to the brain may provide a significant advantage over currently used strategies without damaging the BBB. 158,159 The transport mechanism of NPs across the BBB can be explained by the increased retention of the NPs in the brain blood capillaries in combination with the adsorption of the NPs to the capillary walls. These events lead to a higher concentration gradient, which increases the transport across the endothelial cell layer and thus enhances the delivery to the brain.…”

“…The NPs could permeate the BBB through the tight junctions, which are open between the endothelial cells of the brain blood vessels. 158,160,163 Endocytosis by the endothelial cells followed by the release of the drugs within these cells facilitates delivery to the brain. 164,165 Transcytosis can also facilitate transport through the endothelial cell layer.…”

“…[166][167][168] Finally, a combination of the effects described above can be used ( Figure 3). 158,160,163 NPs can also be administered nasally to promote absorption 169 and delivery to the brain. 160,170,171 Other technological strategies include coating NPs with polyethylene glycol (PEG), 172 polymers, or antibodies to improve nasal absorption.…”