A nanocomposite based on the incorporation of the complex 4'-(4-carboxyphenyl)-2,2':6',2 '' terpyridine triphenylphosphine diacetonitrile ruthenium(II) tetrafluoroborate with multiwalled carbon nanotubes and ionomer supported upon a glassy carbon electrode substrate is reported and characterized with scanning electron microscopy, transmission electron microscopy and infrared spectroscopy. The electrochemical behavior and stability of the composite electrode was investigated via cyclic voltammetry. The modified electrode exhibits an electro-catalytic activity towards the oxidation of both hydrazine and phenyl hydrazine in 0.1 M phosphate buffer solution (PBS, pH 7.4). The oxidation of hydrazine and phenyl hydrazine occurs at 0.81 V and 032 V with limit of detection found to be 3.7 x 10(-7) M and 1.15 x 10(-7) M and having a linear range from 5 x 10(-6) M to 6.5 x 10(-3) M, and 5 x 10(-6) M to 0.2 x 10(-3) M, respectively. (C) 2014 Elsevier Ltd. All rights reserved.