Decoration of carbon nanotubes with biological entities for electronic device applications

The chemical modification of nanoscale materials has created increasing interest in novel hybrids for application in molecular devices. Both single(swnt) and multi-wall carbon nanotubes (mwnt) are an excellent platform for either covalent or noncovalent functionalisation. Due to their enhanced electronic properties, such as enhanced current carrying capacity, carbon nanotubes can also be used as electrical transducers. Immobilisation of biological moieties on carbon nanotubes has been motivated by the prospects of using nanotubes as a new type of sensor platform. Further, the covalent attachment of biological entities, such as antibodies, results in stable and specific reaction sites for sensing applications. In a first step towards developing nanoscale biosensors, we have successfully attached both antibodies (anti-Bovine Serum Albumin) and an enzyme (Soybean peroxidase) to functionalised MWNT via various reaction schemes. The reactions have been completed using both amide- and carboxyl-functionalised MWNT and the resultant material has been characterised using a number of techniques including: atomic force, confocal and transmission electron microscopies, Raman, nuclear magnetic resonance and UV-vis spectroscopies as well as conventional electrochemistry. The biological integrity of the attached antibody (or enzyme) has also been confirmed. The use of carbon nanotubes in various architectures (ie: single tube FET devices, fibres, mats and coatings) is one of the goals of this research and attempts have been made to integrate the biologically functionalised nanotube material as the active transducer element.