Non-enzymatic biosensor based on F,S-doped carbon dots/copper nanoarchitecture applied in the simultaneous electrochemical determination of NADH, dopamine, and uric acid in plasma

Abstract

This work presents the synthesis and characterization of an innovative F,S-doped carbon dots/CuONPs hybrid nanostructure obtained by a direct mixture between F,S-doped carbon dots obtained electrochemically and copper nitrate alcoholic solution. The hybrid nanostructures synthesized were characterized by absorption spectroscopy in the Ultraviolet region (UV-vis), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and different electrochemical techniques. The fluoride and sulfur-doped carbon dots/CuONPs nanostructures were used to prepare a non-enzymatic biosensor on a printed carbon electrode, exhibiting excellent electrocatalytic activity for the simultaneous determination of NADH, dopamine, and uric acid in the presence of ascorbic acid with a detection limit of 20, 80, and 400 nmol L⁻¹, respectively. The non-enzymatic biosensors were also used to determine NADH, dopamine, and uric acid in plasma, and they did not suffer significant interference from each other.