Highly sensitive and selective electrochemical detection of dopamine based on CuCrO2-TiO2 composite decorated screen-printed modified electrode

Abstract

In the present study, a dopamine (DA) sensor was constructed based on a screen-printed carbon electrode (SPCE) combined with CuCrO2-TiO2 composite. The CuCrO2-TiO2 composite was prepared by a self-combustion glycine nitrate process (GNP) and used to the selective and sensitive detection of DA. The prepared CuCrO2-TiO2 composite-modified SPCE electrode revealed an enhanced sensor response to the detection of DA, showing high peak current with less oxidation potential. The surface area and phase evolution of the CuCrO2-TiO2 composite were determined by the glycine-nitrate (GN) ratios. The structures of the prepared material were verified by scanning electron microscopy, X-ray diffraction, and scanning transmission electron microscopy studies. The active surface area of the composite was identified by BET surface area analysis. These studies confirmed the porous structure of the CuCrO2-TiO2 composite. The electrochemical performance of the SPCE/CuCrO2-TiO2 electrode was studied by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry methods. The SPCE/CuCrO2-TiO2 (GN = 1.5) electrode presented distinguished electrocatalytic activity for the detection of DA with a long linear response range (1–230 µM), low detection limit (0.14 µM), and high sensitivity (16.82 µA µM−1 cm−2). The modified sensor also showed outstanding repeatability, storage stability, reproducibility, and along with acceptable practicality.