Electrochemical determination of cadmium ions in biological and environmental samples using a newly developed sensing platform made of nickel tungstate-doped multi-walled carbon nanotubes

Abstract

Simple and rapid analysis of cadmium ion in environmental and biological samples is of great importance due to the severe toxicity caused by this heavy metal. In the present work, nickel tungstate (NiWO4) dispersion was mixed with multi-walled carbon nanotubes (MWCNTs) to obtain a homogenous composite of (NiWO4/MWCNTs) which was assigned as carbon paste electrode modifier. The composite was fully characterized using various characterization techniques including X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Thermo-Gravimetric Analysis (TGA) and Fourier Transform InfraRed (FTIR). The electrochemical redox reactions of cadmium (II) ions at the modified electrode interface were investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and linear sweep voltammetry (LSV). Effective parameters on the electro-analysis assay performance including the electrode composition, types of electrolyte, scan rate and pH were tested to achieve the best effective optimum conditions. Accordingly, a linear relation of cadmium ions was achieved in the concentration range 50–450 µM with limit of detection of 0.12 µM. Besides, the proposed electrode was successfully used to monitor trace amounts of cadmium ions in various real samples. Graphical abstract Schematic illustration of synthesis process of NiWO4/MWCN nanocomposite and its application as high-performance cadmium ion sensors

Construction of Nickel Tungsten Oxide Anchored Carbon Nanofibers Modified with Glassy Carbon Electrode for Enhanced Electrochemical Detection of Metronidazole in Urine and Environmental Water Sample

“…The NiWO 4 has peaks at 2ϴ = 12.82°, 18.21°, 24.72°, 33.56°, 36.80°, 46.93°, 52.24°, 59.73°, 62.55°, 65.80°, and 72.87°, which correspond to the NiWO 4 standard pattern of the cubic structure (JCPDS No:00-015-0755) and the hkl numbers of the planes are (010), (100), (011), (111), (−111), (002), (−121), (202), (−113), (311) and (−232). Hence, the results indicate a high level of purity with the presence of entirely synthesized NiWO 4 material and the successful formation of CNF/NiWO 4 nanocomposite [48][49][50]. Figure4Bdepicts the FTIR spectra of NiWO 4, CNF, and NiWO 4 /CNF nanocomposites.…”

Triangle-Shaped Cerium Tungstate Nanoparticles Used to Modify Carbon Paste Electrode for Sensitive Hydroquinone Detection in Water Samples

“…Pavithra et al reported the sonochemical synthesis of nickel tungstate nanoparticles and their application in photocatalytic dye degradation and electrochemical determination of lead ions in environmental samples [ 34 ]. Mohammed et al evaluated cadmium ion levels in water and urine samples using an electrochemical sensor based on nickel-tungstate-doped multi-walled carbon nanotube composites [ 35 ]. One-dimensional praseodymium tungstate nanoparticles at reduced graphene oxide nanocomposite for sensitive detection of insecticide fenitrothion in water samples is reported by Sundaresan et al [ 36 ], while Goudarzi et al described the development of a photocatalytic degradation platform based on eco-friendly synthesized manganese-doped thallium tungstate nanostructures for efficient removal of various antibiotics from environmental aquatic media [ 37 ].…”