ZIF-8 derived nitrogen-doped porous carbon and nitrogen-doped graphene nanocomposite modified electrode for simultaneous determination of ascorbic acid, dopamine and uric acid
A voltammetric sensor was developed using nitrogen-doped porous carbon and nitrogen-doped graphene nanocomposite modified glassy carbon electrode for simultaneous determination of dopamine (DA), uric acid (UA) and ascorbic acid (AA). Detailed characteristics of nanocomposites were investigated by SEM, TEM, XPS, XRD and FT-IR. Experimental conditions such as accumulation time, accumulation potential and buffer solution pH were optimized. The sensor demonstrated a linear plot of 0.01~15.0 mmol/L for AA, 0.08~350.0 μmol/L for DA, and 0.5~100.0 μmol/L for UA, with detection limit of 1.99 μmol/L, 0.011 μmol/L and 0.088 μmol/L, respectively. The established method exhibited excellent reproducibility, anti-interference and stability, which were applied for DA, UA and AA determination in real urine samples with recoveries between 100.2 % and 102.0%.