Determination of tetracycline in the presence of major interference in human urine samples using polymelamine/electrochemically reduced graphene oxide modified electrode

A polymelamine (p-Mel) film on electrochemically reduced graphene oxide (ERGO) on a glassy carbon (GC) electrode (p-Mel@ERGO/GC) was designed using a potentiodynamic method for the simultaneous and selective determination of tetracycline (TET) in the presence of a major interference, uric acid (UA). The modified surfaces were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and cyclic voltammetry. The surface coverage of the modified electrode was found to be 3.98 x 10(-11) mol cm(-2). The modified p-Mel@ERGO/GC electrode not only enhanced the oxidation currents of the TET and UA, but also shifted their oxidation potential toward a less positive direction compared to the bare GC, GO/GC, ERGO/GC, and p-Mel/GC electrodes. The modified electrode was used effectively for the selective determination of TET in the presence of a 50-fold excess of UA. Differential pulse voltammetry revealed a detection limit of 5 mu M TET. The present modified electrode can be applied to the simultaneous determination of TET and UA in human urine samples. To the best of the authors' knowledge, this is the first report of the simultaneous determination of TET and UA. (C) 2016 Elsevier B.V. All rights reserved.