A carbon nanofiber based biosensor for simultaneous detection of dopamine and serotonin in the presence of ascorbicacid

A biosensor based on an array of vertically aligned carbon nanofibers (CNFs) grown by plasma enhanced chemical vapor deposition is found to be effective for the simultaneous detection of dopamine (DA) and serotonin (5-HT) in the presence of excess ascorbic acid (AA). The CNF electrode outperforms the conventional glassy carbon electrode (GCE) for both selectivity and sensitivity. Using differential pulse voltammetry (DPV), three distinct peaks are seen for the CNF electrode at 0.13 V, 0.45 V, and 0.70 V for the ternary mixture of AA, DA, and 5-HT. In contrast, the analytes are indistinguishable in a mixture using a GCE. For the CNF electrode, the detection limits are 50 nM for DA and 250 nM for 5-HT.

► Carbon nanofiber and glassy carbon electrodes were used for the detection of dopamine and serotonin.
► Carbon nanofibers detected mixtures of dopamine and serotonin in the presence of ascorbic acid.
► Carbon nanofibers electrodes detected down to 50 nM dopamine and 100 nM serotonin.