Rapid and highly sensitive MnOx nanorods array platform for a glucose analysis

A Mn2O3 nanorod array has been successfully prepared by using simple pulse-reverse electrodeposition that was then followed by transformation to a higher MnOx oxidation state via electrochemical oxidation. The surface morphology and composition of the MnOx nanorods was verified via scanning electron microscopy and X-ray photoelectron spectroscopy. The MnOx nanorod array exhibits excellent electrocatalytic activity toward glucose oxidation under alkaline conditions and these properties were confirmed by using cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The structure of the MnOx nanorod array not only provides a large surface area, but also facilitates electron transfer and mass diffusion. The optimum oxidation time was determined to be 30 min, at which the MnOx glucose sensor demonstrated a sensitivity at 811.8 μA mM−1, which is the highest among the various types of MnOx-based sensors that have been reported so far. Moreover, it also exhibited an excellent long-term stability and a good selectivity in the presence of interferents, such as ascorbic acid, dopamine, uric acid, urea, and aspartic acid. The practical applicability of MnOx sensor was also studied by detecting glucose in human serum, in which it demonstrated an excellent selectivity and reliability.