Abstract
Copper oxide doped iron oxide nanocrystals (CuO center dot Fe2O3 NCs) were prepared using a simple hydrothermal technique at low temperature in an alkaline medium. The CuO center dot Fe2O3 NCs were characterized by means of conventional techniques such as Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) combined with X-ray electron dispersive spectroscopy (XEDS), and X-ray photoelectron spectroscopy (XPS). A sensitive and selective uric acid (UA) sensor was developed with the deposition of a thin-layer of doped NCs onto a flat glassy carbon electrode (GCE, surface area: 0.0316 cm(2)) using a coating binder. Enhanced analytical performances such as sensitivity, limit of detection (LOD), limit of quantification (LOQ), linear dynamic range (LDR), and long-term stability of the proposed uric acid sensor were achieved by a reliable current-voltage (I-V) system. The calibration curve was found to be linear (R-2 = 0.8670) over a broad range of uric acid concentrations (100.0 pM-100.0 mM). The sensitivity, LOD, and LOQ of the proposed uric acid sensor were found to be 3.16 x 10(-5) mu A mu M-1 cm(-2), 10.20 +/- 1.0 pM, and 340.0 mM, respectively. The expected CuO center dot Fe2O3 NCs/GCE/Nf sensor was used for real sample analysis to find the uric acid concentration and acceptable results were obtained. This electrochemical approach can be an innovative approach in enzyme-less biosensor development for the assessment of unsafe bio-molecules in the healthcare field.