Preferential Biofunctionalization of Carbon Nanotubes Grown by Microwave Plasma-Enhanced CVD

Multiwalled carbon nanotubes (CNTs) were grown by microwave plasma chemical vapor deposition using dendrimer-templated Fe nanoparticles as a catalyst. Variation of the dc bias voltage and the calcination temperature of the dendrimer-templated Fe 2 O 3 catalyst yielded a matrix of CNT arrays. Samples were immobilized with glucose oxidase, which were used for amperometric cyclic voltammetry experiments. Spectroscopic and electron microscopic characterizations indicate that enzyme adsorption per unit CNT area is higher for samples with lower quality, suggesting that CNTs with higher levels of defect densities are desirable for biosensing applications.