A high-performance electrochemical sensor based on g-C₃N₄-E-PEDOT for the determination of acetaminophen

A fast, ultrasensitive electrochemical sensing platform based on graphitic carbon nitride-electrochemically deposited-poly(3,4-ethylenedioxythiophene) (g-C₃N₄-E-PEDOT) composite was constructed by in-situ electropolymerization and applied for the quantitative determination of acetaminophen (AP). E-PEDOT was introduced as the conducting matrix for developing g-C₃N₄ composite to complement the poor conductivity disadvantage of g-C₃N₄. The strong affinity and synergetic effect between g-C₃N₄ and E-PEDOT, which were analyzed by PM6 computational calculation, highly improved the electron transfer property and remarkably enhanced the electrochemical catalytic activity of the composite. The g-C₃N₄-E-PEDOT modified glassy carbon electrode (GCE) demonstrated better electrocatalytic activity towards the oxidation of AP than bare, g-C₃N₄ and E-PEDOT modified ones. Under the optimized conditions, the oxidation peak currents at the g-C₃N₄-E-PEDOT/GCE increased linearly in the concentration range of AP from 0.01 to 2 μM and 2–100 μM, and an ultra-low limit of detection (LOD) of 34.28 nM was obtained (S/N = 3). In addition, the g-C₃N₄-E-PEDOT/GCE was successfully applied for the AP determination in the clinical human serum, and also exhibited excellent selectivity, reproducibility and stability. Except the novel AP determination approach, moreover, this work provided a new electrochemical application angle of graphitic carbon nitride theoretically as well as experimentally.