Stripping Voltammetry Research Articles

A versatile voltammetric procedure for quantitative determination of Pb(II) directly in environmental water samples has been proposed. Differential pulse technique in the variant of anodic stripping voltammetry was applied to study Pb(II) at a solid bismuth microelectrode (SBiµE). The proposed procedure was tested using model solutions containing 0.1 mol L−1 acetate buffer (pH = 3.4) and 5 × 10−9 mol L−1 Pb(II). Under optimized measurement conditions, i.e., activation potential and time −2.5 V and 30 s, respectively, and accumulation potential and time −1.4 V and 30 s, respectively, a linearity range of 1 × 10−10–3 × 10−8 mol L−1, a detection limit of 3.4 × 10−11 mol L−1 and a relative standard deviation of 3.1% were obtained. The applicability of the developed procedure was confirmed by direct analysis of environmental waters, such as water from the Bystrzyca River and water from the Baltic Sea.

Achieving anodic stripping voltammetric detection of aluminum via Zn-assisted g-C3N4-modified sensor system.

Application of PAMAM-functionalized NH2-MCM-41 modified glassy carbon electrode for quantitative determination of Cu (II) in water samples by using stripping voltammetry

An advanced and sensitive cadmium detection using anodic stripping voltammetry validated by a chemometric approach

Nanomolar simultaneous determination of Cd(II) and Pb(II) using composite carbon material based on PEG-functionalized magnetic nanoparticles (PEG-Fe3O4).

Direct synthesis of C3+ hydrocarbons via the electrochemical CO2 reduction reaction is highly desirable for producing sustainable chemicals. However, this approach remains challenging due to the limited ability of current electrocatalysts to adsorb and couple key reaction intermediates effectively, with promising systems, such as Ni oxyhydroxide-derived catalysts, still exhibiting partial current densities toward C3+ hydrocarbons <0.9 mA cm-2. Motivated by the limited activity and control over the active site environment of these systems, we hypothesize that reducing the size of metallic Ni modifies its electronic states and introduces interfacial metal-support sites that promote more balanced *CO adsorption, critical for facilitating C-C coupling beyond C2 intermediates. Here, we report a plasma-assisted deposition method to synthesize size-controlled metallic Ni nanoislands on a carbon support. Characterization revealed that reducing the nanoisland size (<12 nm) forms undercoordinated, electron-deficient, and strained surfaces with a downshifted d-band center─features associated with weakened *CO binding, favoring intermediate coupling and C3+ hydrocarbon formation. Nanoislands as small as ∼3.5 nm delivered a 120-fold increase in C3+ hydrocarbon specific activity relative to large particles (bulk-like Ni). CO stripping voltammetry shows weaker *CO adsorption on isolated nanoislands. While C3+ partial current densities remain low (∼0.1 mA cm-2), these findings identify nanoparticle size and metal-support interactions as key design parameters for advancing CO2 conversion to long-chain hydrocarbons, offering a foundation for further improvement, as demonstrated by a >20-fold enhancement in the Ni-mass-based activity versus state-of-the-art catalysts.

Herein, we propose an ultrasensitive electrochemical immunosensor based on glucose oxidase labeling and enzyme-catalyzed Au staining. In brief, the primary antibody (Ab1), bovine serum albumin, an antigen and then a bionanocomposite that contains a second antibody (Ab2), poly(3-anilineboronic acid) (PABA), Au nanoparticles (AuNPs) and glucose oxidase (GOx) are modified on a glassy carbon electrode coated with multiwalled carbon nanotubes, yielding a corresponding sandwich-type immunoelectrode. In the presence of glucose, a chemical reduction of NaAuCl4 by enzymatically generated H2O2 can precipitate a lot of gold on the Ab2-PABA-AuNPs-GOx immobilized immunoelectrode. In situ anodic stripping voltammetry (ASV) detection of gold in 8 μL 1.0 M aqueous HBr-Br2 is conducted for the antigen assay, and the ASV detection process takes approximately 6 min. This method is employed for the assay of human immunoglobulin G (IgG) and human carbohydrate antigen 125 (CA125), which demonstrates exceptional sensitivity, high selectivity and fewer required reagents/samples. The achieved limits of detection (S/N = 3) by the method are 0.25 fg mL−1 for IgG (approximately equivalent to containing 1 IgG molecule in the 1 microlitre of the analytical solution) and 0.1 nU mL−1 for CA125, which outperforms many previously reported results.

In this study, we report sensors with interdigitated electrodes functionalized with layer-by-layer (LbL) films of carboxymethyl cellulose (CMC) and chitosan (CHI) for copper ion detection. Variations in CMC/CHI bilayers (1, 3, and 5) and the degree of deacetylation (DD ≈ 95%, 75%, 55%) of high molecular weight chitosans (approx. 106 g/mol) were explored for their impact on electrode sensitivity using anodic stripping voltammetry. Sensors made with 95% deacetylated chitosan exhibited nearly double the current intensity compared to those prepared with lower DD, highlighting the crucial role of amino groups in sensitivity. Rougher films enhanced copper detection, and optimal performance was achieved with three bilayers, demonstrating excellent reproducibility (2% standard deviation). The linear detection range was from 0.5 to 2.5 ppm, with a detection limit of 0.05 ppm. Validation with another analytical technique revealed relative errors ranging from 2.1% to 4.6%, confirming the method’s accuracy. The enhancement mechanism is linked to the physical-chemical characteristics of the CMC/CHI films, where the amino groups of CHI assist in copper ion complexation, improving sensor effectiveness. The control of chitosan’s DD provides a new level of customization in the properties of LbL films, enhancing the sensor’s analytical capability for highly sensitive metal ion detection.

Anovel sulfur-doped graphitic carbon nitride with sulfur-doped carbon quantum dots (S-g-C₃N₄@S-CDs) nanocomposite was synthesized using 5-amino-1,3,4-thiadiazole-2-thiol as a precursor. The nanocomposite was synthesized using thermal condensation and hydrothermal techniques, which exhibited excellent physicochemical properties, as confirmedby X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Field emission scanning-electron microscopy (FE-SEM) analyses. The prepared S-g-C₃N₄@S-CDs nantocomposite was employed to modify the surface of ascreen-printed carbon electrode (SPCE) and was used as a novel electrochemical sensor for the sensitive detection of heavy metals in water and food samples. The electrochemical performance of S-g-C₃N₄@S-CDs was evaluated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Differential pulse anodic stripping voltammetry (DPASV) was employed for the simultaneous determination of Hg2⁺, Cu2⁺, and Pb2⁺ ions in 0.1M HCl (pH, 1) as supporting electrolyte solution. The developed sensor exhibited excellent sensitivity due to the enhanced conductivity and electrocatalytic activity imparted by sulfur doping in the composite material. The linear ranges were 1.5 - 300.0 µgL⁻1 for Hg2+, 16.0 - 600.0 µgL⁻1 for Cu2+ and 26.0 - 1100.0 µgL⁻1 for Pb2+ with the limits of detection (LOD) of 0.56 µgL⁻1 (2.8nM), 6.0 µgL⁻1 (94.0nm), and 10.0 µgL⁻1 (48.3nM) and sensitivity values of 5.5, 1.3 and 0.8 µA µgL-1cm-2, respectively. The applications of the S-g- C₃N₄@S-CDs-based sensor for heavy metal ions were validated in food and water samples, which gave good recoveries in the range from 95.3% to 106.4%, with RSD values below 4.2%, demonstrating the good accuracy and precision of the developed sensor.

The detection and monitoring of mercury ions (Hg2+) in water have become increasingly critical due to their extreme toxicity, bioaccumulation potential, and regulatory significance under international frameworks such as the Minamata Convention. Persistent mercury contamination continues to affect water systems in both developed and developing nations, including India and the United Kingdom. As a step towards detecting mercury (Hg2+) in water samples, we have developed miniaturized point-of–analysis electrochemical sensor based on a new metal-free, thiadiazole (TDA) and triazine (Trz) linked porous organic polymer (TDA-Trz-POP). Unlike conventional sensors that rely on metal-based recognition elements, our heteroatom-rich POP enables highly selective Hg²⁺ capture via synergistic sulphur and nitrogen coordination. The resulting sensors exhibit a lower limit-of-detection (LoD) as 1.5 nM (≈ 0.4 ppb, below the WHO Limit of 6 ppb) and a Linear range of 5–100 nM (1.4 to 27 ppb). The selective and sensitive detection of Hg2+ attributed to the nitrogen- and sulphur-rich surface functionalities of the TDA-Trz-POP-modified electrode, with the underlying binding mechanism is discussed in detail. Using square wave anodic stripping voltammetry (SWASV), we demonstrate real-sample applicability in water, offering a robust, low-cost, and scalable solution for on-site mercury detection in groundwater. The present work is among the first demonstrations of a metal-free porous organic polymer (POP) integrated into SPEs for point-of-analysis mercury sensing with huge potential for public health in developing nations.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-19241-x.

Thallium is a soft metal with a grey or silvery hue. It commonly occurs in two oxidation states in chemical compounds: Tl+ and Tl3+. Thermodynamically, Tl+ is significantly more stable and typically represents the dominant form of thallium in environmental systems. However, in this chemical form, thallium remains highly toxic. This study focuses on the modification of a glassy carbon electrode (GCE) with silver nanostructures stabilised by potato starch derivatives. The modified electrode (GCE/AgNPs-E1451) was used for the determination of trace amounts of thallium ions using anodic stripping voltammetry. Emphasis was placed on assessing the effect of surface modification on key electrochemical performance parameters of the electrode. Measurements were carried out in a base electrolyte (EDTA) and in a real soil sample collected from Bali. The stripping peak current of thallium exhibited linearity over the concentration range from 19 to 410 ppb (9.31 × 10−8 to 2.009 × 10−6 mol/dm3). The calculated limit of detection (LOD) was 18.8 ppb (9.21 × 10−8 mol/dm3), while the limit of quantification (LOQ), corresponded to 56.4 ppb (2.76 × 10−7 mol/dm3). The GCE/AgNPs-E1451 electrode demonstrates several significant advantages, including a wide detection range, reduced analysis time due to the elimination of time-consuming pre-concentration steps, and non-toxic operation compared to mercury-based electrodes.

The reuse of materials for the development of high-performance electrochemical sensors is explored in this work. Specifically, bismuth (Bi) films were electrodeposited using Bi extracted by using an aqueous two-phase system (ATPS) from discarded fusible plugs (BiSn alloy), which are used as safety valves in gas cylinders. The ATPS is an environmentally friendly strategy for liquid-liquid extraction, and its suitability for obtaining purified Bi for use in electrochemistry is demonstrated. As a proof-of-concept, the bismuth film electrodes obtained from extracted Bi (BiATPS-FE) were applied for the simultaneous voltammetric determination of heavy metal species (Cd2+ and Pb2+). By applying square-wave anodic stripping voltammetry (SWASV), BiATPS-FE displayed a similar voltammetric response toward both the analytes compared to bismuth film electrodes prepared from standard Bi precursors (Bi-STD). Under optimized conditions, the BiATPS-FE sensor exhibited linear ranges of 0.50 to 7.0 μmol L-1 and 0.40 to 5.0 μmol L-1 for Cd2+ and Pb2+, respectively, with limits of detection of 0.044 μmol L-1 (Cd2+) and 0.019 μmol L-1 (Pb2+). The developed voltammetric method, adopting BiATPS-FE, was successfully applied to lake water and tea drink samples for the simultaneous determination of Cd2+ and Pb2+, with recovery percentages ranging from 93% to 100%. Furthermore, the proposed sensor (BiATPS-FE) showed good repeatability and reproducibility. The exciting analytical performance verified for the Bi-film electrodes emphasizes the feasibility of combining environmentally friendly materials recovery and electrochemical strategies to propose value-added electrochemical sensors.

Speciation analysis of Sb(III) and Sb(V) by adsorptive stripping voltammetry in the presence of Pyrogallol red

Electrochemical behavior of the synthetic food diazo dye Brilliant Black BN (E151) and the first voltammetric method for its determination.

This study presents the fabrication and evaluation of nanostructured metal oxide-modified electrodes for the highly sensitive electrochemical detection of heavy metal ions in water. Zinc oxide (ZnO) nanorods, titanium dioxide (TiO₂) nanoparticles, and tin dioxide (SnO₂) nanostructures were synthesized via hydrothermal and sol-gel methods and characterized using XRD, SEM, BET, FTIR, and XPS. These analyses confirmed the successful formation of crystalline, high-surface- area, and mesoporous materials with abundant surface hydroxyl groups. The nanostructures were used to modify glassy carbon electrodes (GCEs), which were then assessed using electrochemical impedance spectroscopy (EIS) and differential pulse anodic stripping voltammetry (DPASV). The ZnO nanorod-modified GCE (ZnO/GCE) demonstrated superior performance, achieving the lowest detection limits of 0.4 ppb for Pb²⁺, 0.6 ppb for Cd²⁺, and 0.3 ppb for Hg²⁺, attributed to its optimal morphology and enhanced electron transfer kinetics. The sensors exhibited excellent selectivity, reproducibility (&lt;5% RSD), and long- term stability (&gt;90% response after 4 weeks). This work highlights the significant potential of simple, cost-effective metal oxide nanostructures, particularly ZnO nanorods, as high-performance platforms for on-site water quality monitoring.

This study presents the fabrication and evaluation of nanostructured metal oxide-modified electrodes for the highly sensitive electrochemical detection of heavy metal ions in water. Zinc oxide (ZnO) nanorods, titanium dioxide (TiO₂) nanoparticles, and tin dioxide (SnO₂) nanostructures were synthesized via hydrothermal and sol-gel methods and characterized using XRD, SEM, BET, FTIR, and XPS. These analyses confirmed the successful formation of crystalline, high-surface-area, and mesoporous materials with abundant surface hydroxyl groups. The nanostructures were used to modify glassy carbon electrodes (GCEs), which were then assessed using electrochemical impedance spectroscopy (EIS) and differential pulse anodic stripping voltammetry (DPASV). The ZnO nanorod-modified GCE (ZnO/GCE) demonstrated superior performance, achieving the lowest detection limits of 0.4 ppb for Pb²⁺, 0.6 ppb for Cd²⁺, and 0.3 ppb for Hg²⁺, attributed to its optimal morphology and enhanced electron transfer kinetics. The sensors exhibited excellent selectivity, reproducibility (&lt;5% RSD), and long-term stability (&gt;90% response after 4 weeks). This work highlights the significant potential of simple, cost-effective metal oxide nanostructures, particularly ZnO nanorods, as high-performance platforms for on-site water quality monitoring.

Spectral characteristics of organic matter from algae and its complexation with copper: a case study of Ulva prolifera.

An electrochemical fluorescence dual-mode strategy for HER2-positive breast cancer cell detection.

A β-cyclodextrin/porous graphene ink electrode for smartphone-assisted electrochemical Hg2+ sensing.

This study introduces an improved method for the on-site quantification of cadmium and lead in officinal plants using differential pulse anodic stripping voltammetry (DP-ASV) with a glassy carbon electrode (GCE) modified by an in-situ mercury film (iMF-GCE). Initial experiments, conducted with one-variable-at-the-time (OVAT) approach, have provided suboptimal recovery rates and linearity, factors refined later through a systematic experimental approach involving two different designs: Plackett-Burman and Face Centered Composite Design (FCCD). Certified reference materials confirmed the method's reliability and its potential for effectiveness. The key parameters were optimized, achieving an Edep of -1.20V and a tdep of 195s for optimal performance. The results obtained allowed substantial improvements in accuracy, with recovery rates of 85.8% for Cd and 96.4% for Pb, and significantly lowered detection limits from, 1.54μgL-1 to 0.63μgL-1 for Cd and from 0.15μgL-1 to 0.045μgL-1 for Pb. Validation through field applications demonstrated the method's suitability for the analysis of official plants. Other applications are for environmental monitoring and food safety control.