Simultaneous detection of ascorbic acid, dopamine and uric acid based on vertical N-doped carbon nanosheets/three-dimensional porous carbon

A vertical N-doped carbon nanosheets/three-dimensional porous carbon (3D-KSC/CCSBP) nanocomposite was prepared by carbonizing the Schiff base foam which was vertically grown on 3D-KSC. The Schiff base foam was generated by the condensation of aminaldehyde between p-benzaldehyde and hydrazine hydrate. The morphology and pore properties of 3D-KSC/CCSBP were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, electron energy spectroscopy and nitrogen adsorption/desorption isotherm. Cyclic voltammetry and differential pulse voltammetry were used to study the electrochemical behaviors of 3D-KSC/CCSBP and its catalytic performance against ascorbic acid (AA), dopamine (DA) and uric acid (UA). The results show that the electrochemical sensor based on the 3D-KSC/CCSBP nanocomposite can simultaneously detect AA, DA and UA without interference, and their linear ranges are 1.98 mM–6 mM for AA, 14.1 μM–0.1 mM for DA and 0.45 mM–1.2 mM for UA. The detection limits are 0.66 mM for AA, 4.6 μM for DA and 0.15 mM for UA. In addition, the sensor also has good stability, repeatability and anti-interference ability, which indicates a broad prospect in the future practical detection.