This study describe the construction and characteristics of polymeric membrane electrodes based on 2-acetylpyridine-(IR)-(-)-fenchone azine ligand (A) and 2,6-diacetylpyridine-di-(IR)-(-)-fenchone diazine ligand (B) for determination of copper(U) ions. Optimum performance was observed with a membrane composition (w/w) of A (6): PVC (40): DOP (56): NaTPB (1) for ionophore A and B (7): PVC (50): TMDP (86): NaTPB (1) for ionophore B. Membrane electrode A works satisfactorily in the concentration range of 1.0x 1 0-5 to 1.0x 1 0-1 M with a detection limit of 4.0xlO-6 M and Nernstian slope of 30.0±0.2 mY/decade. Meanwhile, membrane electrode B works in the concentration range of I.Ox 1 0-5 to 1.0x 1 0-1 M with detection limit 2.5xlO-6 M and Nernstian slope of29.I±OA mY/decade. Both of these membrane electrodes exhibit wide pH range (4.0-5.0 and 6.0-10.0 for ligand A and 4.0-8.0 for ligand B) and posses a fast response time of below 20 s and also shelf life period of 3 months. The potentiom.....

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This study aims to develop a modified multiwalled carbon nanotubes paste electrodes based fenchone azine ligand complexes for detecting copper, nickel and mercury. The fenchone diazine ligand complexes were characterized by using nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, scanning electron microscopy and transmission electron microscopy. The electrochemical properties of the modified electrodes were determined using square wave stripping voltammetry, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that under optimal conditions, the electrodes showed a linear range between 0.1 nM and 1.0 µM, 10 nM and 1.0 µM, 5.0 µM and 0.1 mM with the limit of detection of 80 pM, 7.4 nM and 3.7 µM for detection of copper, nickel and mercury respectively. The interferences from Ba2+, Ca2+, Cd2+, Ce3+, Co2+, Cu2+, Pb2+, Mn2+, Mg.....

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The application of multiwalled carbon nanotubes (MWCNTs) paste electrode modified with chloropalladium(II) complex in the analysis of trace nickel is presented in this work. The chloropalladium(II) complex was characterized by fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectronspectroscopy (XPS), scanning electronmicroscope (SEM), and transmissionelectronmicroscope (TEM). Several operational parameters influencing the electroanalytical response of the modified electrode were optimized, such as the different composition of modifier, pH ofthe solution, accumulation potential, and accumulation time. At optimal condition a linear plot for nickel concentration between 10 nM to 1.0 M with a limit of detection 7.4 nM were obtained. The relative standard deviation for the 1.0 M of Ni(II) was 4.0% (n = 5). This study shows that with the exception of Co2+, excess co.....

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Over a decade, the Malaysia National Poison Centre found that 40% of pesticide poisoning cases may be linked to excessive paraquat (PQ) in water, soil, or food, underscoring the widespread impact on public health and emphasising the importance of detecting even trace amounts of PQ residues in the environment. Thus, this study presents a novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) reinforced cadmium sulphide co-anchoring on graphitic carbon nitride (CdS/g-C3N4) nanocomposites for PQ detection. The CdS/g-C3N4 nanocomposite was successfully synthesised and characterised through FTIR, XRD, EDX, FESEM and TEM analysis. The modified electrode (CdS/g-C3N4/MWCNTs PE) exhibited improved electrocatalytic activity, as demonstrated by cyclic voltammetry (CV) and impedance spectroscopy. The CdS/g-C3N4/MWCNTs PE displayed a high CV peak and low Rct value which corresponded to a higher electron transfer rate, reduced charge transfer resistance and enhanced mass transpo.....

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