A PoL/RGO material was successfully synthesized and employed to modify the working electrode for determining Methylparaben (MPB) in medication products through voltammetric techniques. The structure of the nanocomposite was characterized by UV-Visible and Fourier transform infrared spectrum and its application to the MPB electrochemical detection was tested by the cyclic voltammetry and DPV techniques. In the result, the modified PoL-RGO/GCE electrode exhibited a superior response toward MPB by applying the DPV method, compares to using the bare GCE, with a limit of detection, a limit of quantification is 0.20 and 0.70 µM, respectively, and the concentration ranging from 1 to 200 µM. In addition, the repeatability (RSD of 2.2, 1.6, 1.4 for 5, 50 and 100 µM MPB, respectively), and the reproducibility (RSD of 4.7%) of the technique were examined as well.

The features of nanomaterials such as graphene, molybdenum disulfide, carbon nanotubes and quantum dots for unique sensing applicability are mentioned in this review study. Some notable sensors that have been produced are described on the basis of the particular analyte compound to be determined and the functionalization processes that are used. For COVID-19 determination, biocompatible sensors manufactured from these materials capable of determining specific chemical components are also highlighted, which could support efficient and reliable sensing and rapid diagnosis.

In the present article, the synthesis of zeolite imidazole framework-11 (ZIF-11) by ultrasonic-assisted hydrothermal process and its application as an electrode modifier for electrochemical determination of uric acid in urine are demonstrated. The obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherms. It was found that the ZIF-11 with rhombic dodecahedron topology and high surface area (1066 m2.g-1) was synthesized in a certain temperature and found in around 25–40°C, and other crystalline phases of zinc benzimidazolate deferring from ZIF-11 phase were found in less 25°C or higher than 40°C. The ZIF-11 is stable in the pH range 6-10. The modification of glassy carbon electrode was performed with ZIF-67 using the drop-casting procedure. The present ZIF-11 modified electrode was employed to study the electrochemical behavior of uric acid (UA). UA oxidation is catalyzed by this electrode in aqueous buffer solution (pH 7) with a decrease of 70 mV in overpotential compared to glassy carbon electrode. With the differential pulse–anodic stripping voltammetry (DP-ASV) method, the oxidation current of UA versus its concentration shows good linearity in the range 20–540μM ( R = 0.998 ) with a detection limit of 0.48 μM ( S / N = 3 ). The obtained ZIF-11 modified electrode was applied in the detection of UA content in urine samples, and satisfied results were obtained.

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In this paper, we discuss veterinary medicine and its applications in the food industry as well as the risk to the health of humans and animals caused by these residues. We review how the veterinary residues enter and cause some detrimental effects. We also mention two techniques to determine the residue of veterinary medications that exist in food originating from animals, including classic and advanced techniques.Finally, we discuss the potential of various developed methods and compare them with some traditional techniques.