In this experimental work, silver tungstate nanostructures were fabricated by a simple combustion synthesis method utilizing sucrose molecules as a new environmentally friendly fuel and structure-controlling agent. Subsequently, a carbon paste electrode (CPE) was modified with the Ag2WO₄ nanocomposite and an ionic liquid (IL) to exploit the synergistic effects of both materials, yielding a cost-effective and highly efficient platform for the electrochemical detection of Vortioxetine (VRT). The Ag2WO₄/IL-modified CPE exhibited markedly enhanced electrochemical activity compared to the bare electrode, as evidenced by the increased oxidation currents and reduced charge-transfer resistance observed in cyclic voltammetry and electrochemical impedance spectroscopy analyses. The sensor demonstrated excellent linearity across a wide concentration range (0.03-60µM) under optimized conditions, with a detection limit of 0.01µM, indicating high sensitivity in adsorptive differential pulse voltammetry (AdsDPV) measurements. Additionally, the platform displayed excellent selectivity, stability, and reproducibility, with recovery values between 97.0 and 103.3% and relative standard deviation (RSD) values from 2.1 to 3.6%. The findings affirm the potential of the Ag2WO₄/IL/CPE sensor for precise quantification of VRT in biological fluids and pharmaceutical formulations. This work presents a promising electrochemical sensing strategy with potential extensions to other neuroactive drugs in clinical diagnostics.

The present study discusses the successful synthesis of a series of reduced graphene oxide/polypyrrole (rGO/PPy) nanocomposites using an in situ oxidative polymerization method. The focus of the evaluation was on their performance as electrode materials for supercapacitor applications, with assessments conducted using cyclic voltammetry (CV). Specifically, the investigation aimed to elucidate the impact of varying PPy content on the electrochemical characteristics of the rGO/PPy system. Four distinct composites were analyzed, characterized by differing PPy loadings, rGO/PPy5, rGO/PPy10, rGO/PPy15, and rGO/PPy20, measured at a scan rate of 10 mV s⁻¹. The CV profiles revealed quasi-rectangular shapes with pronounced redox peaks, thus confirming the presence of both electric double-layer capacitance (EDLC) and pseudocapacitance within the composite structure. The specific capacitance values were measured at 115.66, 89.20, 230.36, and 189.93 F g⁻¹ for rGO/PPy5, rGO/PPy10, rGO/PPy15, and rGO/PPy20, respectively. Notably, the rGO/PPy15 composite exhibited the highest capacitance, indicating an optimal loading of PPy that promotes efficient charge transfer, enhanced ion diffusion, and optimal utilization of electroactive sites. Lower concentrations of PPy resulted in inadequate redox contributions, while excessive PPy content obstructed the rGO conductive network, impeding charge transport. The observed synergistic interaction between the highly conductive rGO framework and the redox-active PPy matrix facilitates superior charge storage capabilities and stability. In conclusion, this study demonstrates that the optimization of PPy content within rGO/PPy composites significantly enhances their electrochemical performance. The rGO/PPy15 formulation stands out for its excellent combination of high capacitance, substantial reversibility, and robust structural integrity, thereby positioning it as a promising candidate for next-generation high-performance supercapacitor devices.

In this work, we report a novel electrochemical sensor based on a carbon black-incorporated hydrogel-modified screen-printed carbon electrode (CB@hydrogel/ SPCE) for the sensitive and selective detection of L-cysteine (L-Cys). The synergistic combination of conductive carbon black and porous carbon black-alginate/acrylamide hydrogel matrix enhanced the electroactive surface area and facilitated rapid electron transfer, which significantly improved the sensor performance. The CB-hydrogel was characterized by Field Emission Scanning Electron Microscopy (FE-SEM): Fourier transform infrared spectroscopy (FTIR): Cyclic Voltammetry (CV): and Differential Pulse Voltammetry (DPV) techniques. DPV studies revealed the electrochemical oxidation of L-Cys on CB@hydrogel/SPCE followed a diffusion-controlled and quasi-reversible mechanism involving a two-electron transfer process. The sensor exhibited a wide linear range from 5 to 170 µM, with a sensitivity of 1.8 µA mM−1 cm−2, limit of detection (LOD) of 1.26 µM, and limit of quantification (LOQ) of 3.83 µM. The sensor demonstrated an excellent selectivity against common interferents such as ascorbic acid, uric acid, glucose, and dopamine. The practical applicability of the sensor was validated by successful quantification of L-Cys in spiked real samples, including apple juice, orange juice, and yogurt, with high recovery rates and minimal matrix effects. These findings highlight the potential of the CB@hydrogel/SPCE platform for reliable and accurate electrochemical detection of L-Cys in complex food matrices.

Abstract During standard cyclic voltammetry (CV) measurements of Li plating/stripping in a three-electrode Swagelok cell, unusually high residual currents were observed, exceeding typical solid electrolyte interphase and double-layer contributions. Systematic investigation revealed that electrolyte leakage and unintended polarization of cell components, such as the stainless steel working electrode plunger, increased the effective electrode surface area and amplified capacitive effects. The effects of cell design, electrolyte volume and concentration, and working electrode surface roughness on capacitive currents were investigated. Optimizing the cell configuration and controlling the substrate surface significantly reduced residual currents, resulting in increased Coulombic efficiency and improved measurement reproducibility. Comparing CV with galvanostatic cycling with potential limitation further revealed intrinsic differences between the protocols, underscoring the impact of experimental conditions on observed electrochemical behavior. The findings provide a cautionary guide for the electrochemical research community, highlighting the critical role of cell design in ensuring reliable and interpretable measurements.

Structure elucidation, cyclic voltammetry, fluorescence, DFT, biological potency, and in silico profiling of new bivalent transition metal coordination compounds of 7-amino-4H-pyrazolo[3,4-b]pyridinone Ligand

Label-free impedimetric immunosensor for the detection of Fibulin-2 as a novel biomarker for the diagnosis of hypertrophic cardiomyopathy in human saliva.

Lattice matching Fe3P-Cu3P heterointerfaces for efficient hydrogen evolution reaction in alkaline and seawater media.

Conversion/reconversion-driven heterostructure electrode for enhanced electrochemical performances in lithium-ion/sodium-ion batteries and supercapattery.

Rapid and efficient preparation of uranium layers by electrodeposition from aqueous and organic solution systems.

Automated exo-glycosidase-based glycan sequencing on a digital microfluidic system with integrated electrochemical detection of monosaccharides.

Fructose-silica polymer composite nanomaterials for resveratrol delivery and electrochemical sensing: Preliminary evaluation in brain glioma cells.

Bisphenol A sensing using carbon fibre transducers with and without metal-organic frameworks modification: towards greener tools for fish safety and surveil ecosystems.

Revealing the analytical potential of thin organic film electrodes: Electrochemical insights into anticancer drug docetaxel at liquid|liquid interfaces.

Smartphone-enabled detection of urea in animal feed based on a disposable electrode modified with silver nanoparticles decorated on nitrogen-doped graphene nanoplatelets.

Electrochemical detection of eugenol and cadmium using cyclic voltammetry: Implications for complexation interaction and quantitative determination

4-Phenyl isothiocyanate modified electrode based on diazonium electrodeposition for heavy metals detection in pharmaceuticals.

Ultrasensitive electrochemical aptasensor for Pseudomonas aeruginosa detection using N-doped MWCNTs/AgNPs nanocomposite.

A 3D printed platform for sample treatment and detection of phytic acid in spinach leaves using a paper-based electrochemical biosensor.

Facile engineering of the 2D flaky structured bismuth yttrium oxide for the electrochemical detection of carbofuran in staple food samples.

HighlightsDesign of easy fabricate and low-cost graphite rotation disk electrode.Effect of background in cyclic voltammetry analysis.