Impact of gadolinium oxide with functionalized carbon nanosphere: A portable advanced electrocatalyst for pesticide detection in aqueous environmental samples.

In this study, we developed a portable electrochemical sensor for realizing the pesticide residue in biological, environmental, and vegetable samples. A lower concentration of carbendazim pesticide (CBZ) was electrochemically exposed by newly developed gadolinium oxide/functionalized carbon nanosphere modified glassy carbon electrode (Gd2O3/f-CNS/GCE). The Gd2O3/f-CNS composite was prepared by two-pot ultrasonic-assisted co-precipitation method and characterized by various physicochemical analytical techniques. In addition, the electrocatalytic activity of the composite was investigated by cyclic voltammetry (CV) towards the detection of CBZ. Besides, the Gd2O3/f-CNS/GCE exhibited excellent electrocatalytic capability and sensitivity towards the oxidation of CBZ due to its high electrochemical active surface area, good conductivity, and fast electron transfer ability. A wide linear range of CBZ (0.5-552 µM) was attained with a low level of detection (LOD) of 0.009 µM L-1 and exceptional stability of 93.41%. The proposed sensor exemplifies practical feasibility in blood serum, water, and vegetable samples with an remarkable recovery range of 96.27-99.44% and primary current response of ∼91% after 15 days.

Temperature abetted synthesis of novel magnesium stannate nanoparticles assisted for nanomolar level detection of hazardous flavonoid in biological samples.

Fabrication of temperature-influenced nanoparticles over the superficial region of glassy carbon electrode (GCE) stimulates the electrocatalytic activity owing to their morphology, defective sites, and higher active surface area, etc. In this regard, we have fabricated annealed magnesium stannate nanoparticles (Mg2SnO4 NPs) on GCE for nanomolar level detection of hazardous flavoring and pharmaceutical compound Rutin (RT). To analyze the impact of temperature, we have compared annealed Mg2SnO4 NPs with unannealed magnesium stannate hydrate (MgSnO3·3H2O) particles. The physicochemical properties of synthesized materials were characterized with different microscopic and spectroscopic techniques. From these studies, annealed Mg2SnO4 NPs formed purely without any flith and existence of water molecules as compared to unannealed MgSnO3·3H2O. Moreover as fabricated, Mg2SnO4 NPs/GCE outcomes with higher redox behavior compared to other electrodes in presence of RT at optimized working buffer (pH = 7.0). Interestingly, the electrode successfully established a dual wider linear response (0.062-34.8 & 34.8-346.8 µM) with a nanomolar detection limit (1 nM) and higher sensitivity. The practicability analysis of the proposed sensor also affords excellent selectivity, reproducibility, repeatability, reversibility, and storage stability. Furthermore, the real sample analysis was carried out in blood and orange samples fallout with better recovery results.

Electrochemical detection of thiamethoxam in food samples based on Co3O4 Nanoparticle@Graphitic carbon nitride composite.

Thiamethoxam is a class of neonicotinoid insecticide widely used in agriculture. Due to their high water solubility, thiamethoxam can be transported to surface waters and have the potential to be toxic to human life. Herein, a simple and robust method is presented for the detection of thiamethoxam based on hydrothermally synthesized nanoparticles of cobalt oxide into the graphitic carbon nitride composite (Co3O4@g-C3N4 NC). The materials were well characterized by XRD, FT-IR, XPS, FESEM, HRTEM, EDX, and UV-vis which provide crystalline nature, structure, and composition. The impedance measurement shows an intimate electrode/electrolyte interface by casting Co3O4@g-C3N4 onto a screen-printed carbon electrode (SPCE), delivering an interfacial resistance as low as 12.5 Ωcm2. The cyclic voltammetry and differential pulse voltammetry measurements exhibit the nanocomposite as a superior electrocatalyst for the electrochemical detection of thiamethoxam and achieved a low detection limit of 4.9 nM with a wide linear range of 0.01-420 µM. The present work also demonstrates a promising strategy for electrochemical detection of thiamethoxam in real samples such as potato and brown rice.