Electrochemical preparation and the characterizations of poly(3,5-diamino 1,2,4-triazole) film for the selective determination of pyridoxine in pharmaceutical formulations

This work describes the synthesis and characterization of a polymeric film of 3,5-diamino 1,2,4-triazole on a pencil graphite electrode for the selective sensing of pyridoxine (PY). The PGE was modified using the electropolymerization process by the potentiodynamic method. The polymerized electrode (PDAT/PGE) was characterized by IR, SEM, AFM, cyclic voltammetry, and electrochemical impedance spectroscopy. PY undergoes irreversible oxidation at 0.79 V on PDAT/PGE in phosphate buffer of pH 5. Using the differential pulse voltammetric technique (DPV), PY showed a linear range from 5 to 950 μM with a lower detection limit of 2.96 μM. The PDAT/PGE was applied for the analytical determination of PY in pharmaceutical tablets with good recovery.

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Supplementary Information

The online version contains supplementary material available at 10.1007/s11696-023-02777-5.

A modified carbon paste electrode with N-rGO/CuO nanocomposite and ionic liquid for the efficient and cheap voltammetric sensing of hydroquinone in water specimens

This paper reports a voltammetric sensor based on copper oxide nanoparticles on nitrogen-doped reduced graphene oxide nanocomposite (N-rGO/CuO)-ionic liquid modified carbon paste electrode (N-rGO/CuO-ILCPE) for determining the hydroquinone (HQ). The N-rGO/CuO was prepared by a facile protocol, followed by characterization via fourier transform-infrared (FT-IR) patterns, field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) analysis. The electrochemical behaviour was linearly symmetrical to various hydroquinone levels (1.0-600.0 μM) with a narrow limit of detection (LOD = 0.25 μM). The diffusion coefficient was also estimated to be 4.1 × 10^-6 cm²/s. The N-rGO/CuO-ILCPE was impressively applicable in determination of hydroquinone in the real specimens.

Transition metal copper composite ionic liquid self-built ratiometric sensor for the detection of paracetamol

In this paper, a MOF derivative Cu-PF₆-MOF composed of transition metal copper and ionic liquid [BMIM] PF₆ was used to construct a ratiometric electrochemical sensor for paracetamol detection. Cu-PF₆-MOF was synthesized by chemical bath method and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), X-ray Photoelectron Spectroscopy (XPS) and X-ray powder diffraction (XRD). Owing to the introduction of ionic liquid [BMIM] PF₆ and the synthetic effect on transition metal copper and ionic liquid [BMIM] PF₆, Cu-PF₆-MOF has the higher conductivity, larger electroactive surface area and better intrinsic catalytic properties of the skeletal transition metal, exhibiting enhanced electrocatalytic response to the reduction of paracetamol. The stable reduction peak at -104 mV was used as the ratiometric signal for analytical paracetamol detection using differential pulse voltammetry (DPV), with a linear range of 0.1-100 μM and a detection limit of 0.03 μM (S/N = 3). In addition, the constructed sensor showed good reproducibility, stability and interference resistance, as well as ideal recoveries (98.20%-104.40%) for the analysis of paracetamol in water samples.

Application of magnetic nanomaterials in electroanalytical methods: A review

Magnetic nanomaterials (MNMs) have gained high attention in different fields of studies due to their ferromagnetic/superparamagnetic properties and their low toxicity and high biocompatibility. MNMs contain magnetic elements such as iron and nickel in metallic, bimetallic, metal oxide, and mixed metal oxide. In electroanalytical methods, MNMs have been applied as sorbents for sample preparation before the electrochemical detection (sorbent role), as the electrode modifier (catalytic role), and the integration of the above two roles (as both sorbent and catalytic agent). In this paper, the application of MNMs in electroanalytical methods have been classified based on the main role of the nanomaterial and discussed separately. Furthermore, catalytic activities of MNMs in electroanalytical methods such as redox electrocatalytic, nanozymes catalytic (peroxidase, catalase activity, oxidase activity, superoxide dismutase activity), catalyst gate, and nanocontainer have been discussed.