Electrochemical Sensing of Theophylline using Modified Glassy Carbon Electrode

In this work, three dimensional NiO nanowrinkles (3D NiO-NWs) were prepared and used as electrode materials to modify the surface of a glassy carbon electrode (3D NiO-NWs/GCE). Then, differential pulse voltammetry (DPV), cyclic voltammetry (CV) and chronoamperometry (CHA) were employed to determine the electrochemical response of theophylline on as-fabricated sensor. The electrochemical theophylline oxidation was elevated on the modified electrode. The peak current on the modified electrode in phosphate buffer solution (PBS, 0.1 M, pH=7.0) showed a linear elevation with an increase in the theophylline concentration (0.1-900.0 mu M), with a narrow detection limit of 0.03 +/- 0.001 mu M.