A Carbon‐Black‐Doped Molybdenite‐Based Electrochemical Sensor for Simultaneous Determination of Uric Acid, Dopamine, and Ascorbic Acid

Abstract

A simple, rapid, cost-effective and non-enzymatic amperometric sensor for sensitive and simultaneous determination of uric acid (UA), dopamine (DA), and ascorbic acid (AA) was developed based on a new combination of carbon black (CB) and molybdenite (MLN) modified glassy carbon electrode (GCE). The synergistic effect of CB and MLN can increase electrode's conductivity, accelerate the electrochemical catalytic reaction and enhance the oxidation currents of UA, DA and AA. Cyclic voltammetry demonstrated the sensor to perform excellently in the electrochemical oxidation of AA, DA and UA, respectively. The oxidation potentials are well separated (oxidation peaks at À 50 mV, 200 mV and 350 mV vs. Ag/ AgCl) for AA, DA and UA with the detection limits of 5 μmol/L, 8.7 μmol/L and 9 μmol/L (S/N = 3), respectively. The MLN-CB/ GCE sensor also demonstrated superior electrochemical properties including good stability, selectivity and reproducibility. In addition, the prepared sensor for UA allowed the determination of UA in highly diluted body fluids (urine), and the analytical results obtained by the present sensor were in good agreement with those obtained by conventional spectrophotometry.

Development of a Cu@ERGO-p(L-Lys) Modified GCE Electrochemical Sensor for the Simultaneous Detection of Ascorbic Acid, Dopamine, and Uric Acid

“…When the novel fabricated electrode is compared with previous research, it produces much lower LOD values than others. 2,18,27,48,49 The LOD values for AA, DA, and UA were 1562.5, 15.1, and 23.8 times lower than the ERGO electrode 28 and 12.5, 3, and 7.1 times lower than the ERGO-p(L-Lys) electrode, 18 respectively. As a result, the developed sensor shows excellent analytical performance for AA, DA, and UA analysis.…”