Oxygen biosensor based on carbon nanotubes directly grown on graphitic substrate

Films of carbon nanotubes were synthesized on the graphitic substrates by CVD method in the presence of catalyst. Two different catalysts were used, that is nickel and iron, supported on graphitic substrates. The as-obtained nanotubes were analyzed by SEM imaging with EDX and Raman spectroscopy. The results revealed their multi-walled morphology. Free radical reaction was carried out in order to chemically functionalize synthesized CNT-forests. Naphthyl moieties were attached to the carbon network and modified electrode served as a platform for the adsorption of redox enzyme – bilirubin oxidase. Electrodes covered with enzyme functionalized CNT-forests were tested as oxygen sensors based on the mediatorless biocatalytic oxygen reduction.