Tellurium-nanowire-coated glassy carbon electrodes for selective and sensitive detection of dopamine

Tellurium-nanowire-coated glassy carbon electrodes (TNGCEs) have been fabricated and employed for selective and sensitive detection of dopamine (DA). TNGCEs were prepared by direct deposition of tellurium nanowires, 600 ± 150 nm in length and 16 ± 3 nm in diameter, onto glassy carbon electrodes, which were further coated with Nafion to improve their selectivity and stability. Compared to the GCE, the TNGCE is more electroactive (by approximately 1.9-fold) for DA, and its selectivity toward DA over ascorbic acid (AA) and uric acid (UA) is also greater. By applying differential pulse voltammetry, at a signal-to-noise ratio of 3, the TNGCE provides a limit of detection of 1 nM for DA in the presence of 0.5 mM AA and UA. Linearity (R2 = 0.9955) of the oxidation current at 0.19 V against the concentration of DA is found over the range 5 nM–1 μM. TNGCEs have been applied to determine the concentration of dopamine to be 0.59 ± 0.07 μM in PC12 cells.

► We have developed Tellurium-nanowire-coated glassy carbon electrodes (TNGCEs) for selective and sensitive detection of dopamine. ► TNGCEs were further coated with Nafion to improve their selectivity and stability. ► The Nafion-treated TNGCE relative to a bare GCE is more electroactive (by approximately 1.9-fold) and selective for dopamine (DA). ► In the presence of 500 μM of ascorbic acid and uric acid, the TNGCE provides an LOD of 1 nM for DA, with good linearity from 5 nM to 1 μM. ► The practicality of TNGCEs has been further validated by quantifying the concentration of dopamine in PC12 cells.