Filling carbon nanotubes for nanobiotechnological applications

Abstract

With the great development in new filling methodologies for preparing endohedral carbon nanotubes, encapsulation strategies employing biomedically relevant molecular guests have emerged rapidly in recent years. All of these hybrid nanomaterials feature distinct properties and potential applications depending on both the chemical nature and spatial arrangement of the encapsulated molecular guests. In this focus article, we discuss the most significant examples in which carbon nanotube (CNTs) hybrids, filled with suitable molecular species, are used for biomedical applications. CNTs containing strongly emitting molecules hold great promises for diagnostic devices, whereas those filled with radioactive species and magnetically-active nanoparticles are attracting considerable attention for theranostic applications. Examples describing the use of the CNTs' tubular cavity as an active reservoir for the controlled release of drugs are also discussed. This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2014

Carbon Nanotubes as an Effective Opportunity for Cancer Diagnosis and Treatment

“…As already mentioned, CNTs exhibit properties that can be exploited for designing excellent drug nano-vectors. Some of these features are, for example: enhanced EPR effect [134], a needle-like shape that facilitates transmembrane penetration and intracellular accumulation [135,136] and the easiness of molecule loading onto the surface or within the interior core of CNTs via both covalent and non-covalent interactions [137,138,139,140]. …”

Lanthanide light for biology and medical diagnosis

“…(iii) In view of the possible toxicity of QDs, analytical chemists have been investigating the potentiality of carbon nanodots (CND or C-dots, [9]) and nanotubes (CNT, [10]). The field is fairly new, Cdots having been discovered in 2004 and quantitative and comparative data are still scarce, but the carbon particles appear to be biocompatible, non-toxic, easily derivatizable, and their fluorescence properties can be tuned by modifying their size and/or surface.…”

Carbon nanotubes allow capture of krypton, barium and lead for multichannel biological X-ray fluorescence imaging

“…The shielding provided to biological systems by this graphene membrane system from the toxic influence of lead and barium as ‘heavy' metals, further illustrates its flexible utility. The elements used as high-contrast tags were chosen primarily according to their unique spectral and hence illustrative potential; given the range of CNT fillings already reported6753, there is no doubt that many alternative tags are available. This research anticipates the creation of a highly multiplexed library of XRF contrast agents that employ a wide range of elements; the use of binary and higher elemental combinations could even enable a complete cellular ‘barcode' system.…”

“…Additional modes of imaging can also be readily envisaged, for example, through the use of magnetic resonance imaging- or radiochemically active elemental fillings. Although today there are significant hurdles53 to the use of filled CNT XRF contrast agents in imaging live humans for healthcare (X-ray safety, radiation penetration depths and governmental approval of internal use of CNTs being chief among them), this technology could be used in the near future for highly illustrative ex vivo imaging of animal models.…”