Carbon Nanotube: A Versatile Carrier for Various Biomedical Applications

With the development of nanotechnology different biological nanomaterials have been developed, out of these, Carbon Nanotubes (CNTs) have attracted attention of various scientists as a carrier for the delivery of therapeutic agents. CNTs are third allotropic form of carbon-fullerenes which consist of graphite sheet rolled up into a cylindrical tube. They have nanometer scale diameter with high aspect ratio. CNTs exist in two forms, single-wall (SWCNTs) and multiwall (MWCNTs) depending on the number of graphene layer they are surrounded with as well as to the method of synthesis. Techniques have been developed to produce nanotubes in sizeable quantities, including Electrical arc discharge, Laser ablation, Chemical vapor deposition, Gas phase catalytic processes, as they tend to strip carbon atoms off from the carbon bearing compounds. Various techniques are available for the evaluation of CNTs which mainly involve the estimation of purity, functionalization and structure variations. Presence of impurities in the CNTs makes them vulnerable to be used as carrier in drug delivery hence CNTs need to undergo purification. To integrate into biological system CNTs can be loaded with active molecules by forming stable covalent bonds or supramolecular assemblies based on non-covalent interactions. Functionalized CNTs have been remarkably shown to exert their potential benefits in drug delivery, drug targeting and various other fields such as diagnostic, tissue regeneration. This review attempts to highlight all aspects of CNTs such as their structure, characterization, synthesis and purification, functionalization, bio-compatible applications in the clinical science and toxicity related issues due to CNTs.