The development of coenzyme Q(10) (CoQ(10)) based electrochemical sensor for the detection of oxidative stress initiators is described for the first time. The sensor relies on CoQ(10) redox properties. CoQ(10) was immobilized at the surface of glassy carbon electrodes (GCE) in combination with cyclodextrins (CD), alpha-CD or beta-CD, that ensure the formation of a well dispersed CoQ(10) film. Nanostructured thin films of CoQ(10) alone and in complexes with alpha-CD or beta-CD at the electrode surface were characterized by scanning electron microscopy (SEM) and Fourier-transformed infrared spectroscopy (FTIR), enabling to identify the morphology of the films and the interactions between the CoQ(10) and CD. Nafion (R) was used to ensure sensor stability. The optimization of the CoQ(10) sensor configuration was made by assessing CoQ(10) redox properties through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), correlated with the results obtained from SEM and FTIR characterization. Next, the sensor in the optimized configuration, GCE/alpha-CD + CoQ(10)/Nafion (R), was applied for the detection of oxidant molecules, hydrogen peroxide and the superoxide radical, through the evaluation of the CoQ(10) redox properties monitored by fixed potential chronoamperometry and square wave voltammetry (SWV). (C) 2019 Elsevier Ltd. All rights reserved.