Long Term Determination of Dopamine and Uric Acid in the Presence of Ascorbic Acid Using Ytterbia/Reduced Graphene Oxide Nanocomposite Prepared Through a Sonochemical Route Publisher



Jafari H¹ ; Ganjali MR^{1, 2} ; Dezfuli AS¹ ; Faridbod F^{1, 2} Show Affiliations
Source: Applied Surface Science Published:2018

Abstract

Decoration of reduced graphene oxide (RGO) with nano-size inorganic particles creates a class of composites with considerably improved characteristics. Improvements in the function of electrochemical energy-storage devices, catalysts and sensors using such particles, have hence attracted a great deal of interest to the area. This manuscript tends to report the results of the research on the application of a sonochemical route for anchoring nano-sized Yb 2 O 3 (Ytterbia) particles, on sheets of RGO. The anchoring phenomenon is based on the self-assembly of the Yb 2 O 3 nano-particles under sonochemical treatments in an ultrasonic bath. To evaluate the method, the produced Yb 2 O 3 -RGO nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), which proved the uniform distribution of the nano-particles on the RGO sheets. Additionally, the Yb 2 O 3 -RGO nano-composites were evaluated through cyclic voltammetry (CV), to assess the potentials of their application in electrochemical devices. The high activity of the produced Yb 2 O 3 -RGO nanocomposites can be attributed to the synergistic effect between Yb 2 O 3 and RGO as well as the porous structure of the nanocomposite. Due to their stability, electrocatalytic properties and large accessible surface area, the low detection limit sensor is usable for long term usages in blood serum and wide linear dynamic range. There are linear relationships between current intensities and concentrations in the region 0.3–800 μM dopamine (DA), and 0.2–210 μM uric acid (UA), and the limits of detection (LOD) (S/N = 3) are down to 0.02 μM and 0.01 μM for DA and UA, respectively in 0.5 mM solution of ascorbic acid. © 2017 Elsevier B.V.