Current Perspective of Carbon Nanotubes Application in Neurology.

The recent advances in nanotechnology have allowed new fields of research to investigate cutting edge brain-specific therapies and to tackle the complex brain-related disorders. The blood-brain barrier (BBB) is a major obstacle for drug delivery to the brain resulting in only few drugs reaching the market to tackle brain disorders. Nanoparticles (NPs) provide a flexible platform for conjugating drugs and targeting ligands and have been extensively researched to facilitate BBB crossing and effective delivery to the brain. In addition, the inherent properties of NPs are being utilized to facilitate other therapeutic possibilities. One example is carbon nanotubes (CNTs), which exhibit several attractive characteristics allowing their use in the brain environment. The properties include a high aspect ratio, the ability to penetrate biological membranes due to their tubular shape and their infrared absorption properties. In this chapter, we review major advances in using CNTs for treating brain tumor and degenerative diseases with special focus on their abilities to cross the BBB following systemic administration, which is the major obstacle for most other NPs.

Multiphoton luminescence imaging of chemically functionalized multi-walled carbon nanotubes in cells and solid tumors.

The intrinsic nonlinear photoluminescence (PL) property of chemically functionalized multi-walled nanotubes MWNTs (f-MWNTs) is reported in this study. f-MWNTs are imaged in fixed lung epithelial cancer cells (A549) and Kupffer cells in vitro, and in subcutaneously implanted solid tumors in vivo, for the first time, using multiphoton PL and fluorescence lifetime imaging (FLIM). Multiphoton imaging in the near-infrared excitation region (∼750-950 nm), employed in this study in a label-free manner, provides sensitivity and resolution optimal to track f-MWNTs within intra-cellular compartments and facilitates tumour imaging and sentinel lymph node tracking in vivo. Wider applications include employing this technique in live imaging of f-MWNTs in biological milieu to facilitate image-guided drug delivery.