Azure B Nanocomposites of Chemically and Electrochemically Produced Graphene Oxide: Comparison of Amperometric Sensor Performance for NADH

Graphene oxide (GO) can interact with positively charged aromatic compounds because it has oxygen-containing functional groups, such as -OH, C=O, and O-C-O. This advantage is generally used to produce composite structures using GO sheets. This paper describes the formation of Azure B nanocomposites with GO samples, produced with electrochemical and chemical procedures. All materials produced at this paper was characterized by using X-ray diffraction, X-ray photoelectron spectroscopy, scanning tunneling microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, UV-visible absorption spectroscopy, and cyclic voltammetry techniques. Electrochemical performance of these two nanocomposites was compared through electrooxidation of NADH and nanocomposite of electrochemically prepared GO demonstrated better performance than that of chemically fabricated GO. When the sensor was applied as an amperometric sensor for quantification of NADH, it revealed a sensitivity of 0.51 mu A mu M-1 cm(-2) and a detection limit of 0.15 mu M, with a linear range of 050-508 mu M. Moreover, the sensor exhibited good amperometric, successive usage, and long-term usage stability and reproducibility.