A novel fabrication of Fe3O4 nanotubes (NT) on FID as nanoelectrode for enzyme-free glucose-sensing application is described. The structural transformation of Fe3O4 NT occurs on, first, immersion of a ZnO nanowire into an aqueous solution of FeCl3, and, subsequently, annealing in air and in vacuum. A tube-like morphology, with length several micrometres and diameter similar to 100 nm, was observed with a scanning electron microscope. Those NT were confirmed to pcissess Fe3O4 in a cubic phase upon structural and composition analysis with X-ray diffraction, and Raman and X-ray photoelectron spectra. The directly grown Fe3O4 NT array is mechanically stable and provides an excellent electrochemical sensing platform. Showing excellent electrocatalytic response to glucose with detection limit 0.1 mu M, rapid response and great sensitivity with 3 ranges of linear relation for the amperometric detection of glucose, this array electrode is readily applicable to other analytes and has great prospective applications in electrochemical detection. (C) 2017 Elsevier B.V. All rights reserved.