Biosensor Application of Carbonaceous Nanocoil Material: Preparation, Characterization, and Determination of Dopamine and Uric Acid in the Presence of Ascorbic Acid

Abstract

Carbonized electrode materials were prepared from carbonization of graphene nanoribbon (GNR) / coal tar pitch (CTP) composite (m% of GNR: 1%, 3%, 5% and 10%). The carbonized materials were denoted as follows: CTP-GNR1, CTP-GNR2, CTP-GNR3 and CTP-GNR4. Characterization included cyclic voltammetry (CV), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). CTP-GNR1 was obtained as the nanocoil structure via SEM. Electrocatalytic activity for some redox probes, such as ferrocene and ferric/ferrous (K3Fe(CN)6 and K4Fe(CN)6) probe on the CTP-GNR1 modified glassy carbon (GC/CTP-GNR1) was found to be greater than others. The nanocoil material (CTP-GNR1) was used in the determination of dopamine (DA) and uric acid (UA) by differential pulse voltammetry (DPV). The electrode exhibits linear responses to DA and UA in the ranges of 2 μM–20 μM in the presence of 300 μM of L-ascorbic acid (AA). The detection limits (S/N = 3) for DA and UA are 3 nM and 6 nM, respectively.