glassy carbon electrode modified with a nickel(II) norcorrole complex and carbon nanotubes for simultaneous or individual determination of ascorbic acid, dopamine, and uric acid

The authors report on the synthesis of a hybrid material consisting of the porphyrinoid metal complex nickel(II) norcorrole that was noncovalently bound to carbon nanotubes (CNT-NiNC). The hybrid was characterized by UV-vis, FTIR spectroscopy, and thermogravimetric analysis. The CNTNiNC hybrid possesses high catalytic activity and selectivity toward the oxidation of ascorbic acid, dopamine, and uric acid. It was used to modify a glassy carbon electrode which then is shown to enable simultaneous or individual determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA) at pH 6.5 and typical working potentials of -70, 200 and 380 mV (vs. SCE). The detection limits (at an SNR of 3) are 2.0 mu M for AA, 0.1 mu M for DA, and 0.4 mu M for UA.