Voltammetric Determination of Bisphenol A in Water and Juice Using a Lanthanum (III)-Doped Cobalt (II,III) Nanocube Modified Carbon Screen-Printed Electrode

Electrochemical Sensors in the Food Sector: A Review

In a world that is becoming increasingly concerned with health, safety, and the sustainability of food supply chains, the control and assurance of food quality have become of utmost importance. This review examines the application and potential of electrochemical sensors in the dynamic field of food science to meet these expanding demands. The article introduces electrochemical sensors and describes their operational mechanics and the components contributing to their function. A summary of the most prevalent electrochemical methods outlines the diverse food analysis techniques available. The review shifts to discussing the food science applications of these sensors, highlighting their crucial role in detecting compounds in food samples like meat, fish, juice, and milk for contemporary quality control. This paper showcases electrochemical sensors' utility in food analysis, underscoring their significance as powerful, efficient tools for maintaining food safety and how they could transform our approach to global food quality control and assurance.

Construction and Application of an Electrochemical Sensor for Determination of D-Penicillamine Based on Modified Carbon Paste Electrode

D-penicillamine (D-PA) is a sulfur-containing drug that has been used for various health conditions. However, like any medication, overdosing on D-PA can have adverse effects and may require additional treatment. Therefore, developing simple and sensitive methods for sensing D-PA can play a crucial role in improving its efficacy and reducing its side effects. Sensing technologies, such as electrochemical sensors, can enable accurate and real-time measurement of D-PA concentrations. In this work, we developed a novel electrochemical sensor for detecting D-PA by modifying a carbon paste electrode (CPE) with a multi-walled carbon nanotube-Co3O4 nanocomposite, benzoyl-ferrocene (BF), and ionic liquid (IL) (MWCNT-Co3O4/BF/ILCPE). Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry (CHA) were employed to explore the electrochemical response of D-PA on the developed sensor, the results of which verified a commendable electrochemical performance towards D-PA. Under optimized conditions, the developed sensor demonstrated a rapid response to D-PA with a linear dynamic range of 0.05 μM-100.0 μM, a low detection limit of 0.015 μM, and a considerable sensitivity of 0.179 μA μM-1. Also, the repeatability, stability, and reproducibility of the MWCNT-Co3O4/BF/ILCPE sensor were studied and showed good characteristics. In addition, the detection of D-PA in pharmaceutical and biological matrices yielded satisfactory recoveries and relative standard deviation (RSD) values.

Development of a novel green catalyzed nanostructured Cu(II) macrocyclic complex-based disposable electrochemical sensor for sensitive detection of bisphenol A in environmental samples

BPA is an endocrine disruptor and the leading environmental pollutant due to its use as raw material in industries. Therefore, the present work reports the sensitive, efficient, and disposable electrochemical paper-based SPE for determining the BPA sensor using an amide-based macrocyclic complex (nanostructured complex of copper acetate with macrocyclic ligand, i.e., CuL (CH3COO)2) synthesized using Citrus limon (lemon) extract via sonication for the first time. The structural, morphological, and electrochemical analyses have been characterized by mass spectroscopy, FTIR, UV-Vis, XRD, FESEM-EDX, elemental mapping and electrochemical techniques. The sensor platform for detecting BPA was fabricated by simple drop-casting on the disposable paper-based SPE using macrocyclic complex, i.e., CuL (CH3COO)2/SPE. After optimizing the conditions, CuL (CH3COO)2/SPE electrode was employed for determining BPA via CV with a wide linear range of 31 × 10-9 μM-0.205 μM, low LOD of 0.027 nM, and high sensitivity of 49.71 μA (log nM)-1 cm-2 having correlation coefficient (R2) of 0.976 which is quite better in compared to other reported SPE sensor for detection of BPA. Further, our sensor also showed good selectivity and reproducibility, in addition to detecting BPA in environmental samples (tube well water, river water and drain water) with acceptable recoveries and RSDs values. In this work, the combination of macrocyclic complex and paper-based SPE has turned out to be a cost-effective electrochemical sensor.

Facile Chemical Synthesis of Co-Ru-Based Heterometallic Supramolecular Polymer for Electrochemical Oxidation of Bisphenol A: Kinetics Study at the Electrode/Electrolyte Interface

Regardless of the adverse effects of Bisphenol A (BPA), its use in industry and in day-to-day life is increasing at a higher rate every year. In the present study, a simple and reliable chemical approach was used to develop an efficient BPA sensor based on a Co-Ru-based heterometallic supramolecular polymer (polyCoRu). Surface morphology and elemental analysis were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Furthermore, functional group analysis was accomplished by Fourier transform infrared spectroscopy (FT-IR). UV-vis spectroscopy was used to confirm the complexation in the ratio of 0.5:0.5:1 (metal 1/metal 2/ligand). Electrochemical characterization of the synthesized polyCoRu was conducted using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analyses. The study identified two distinct linear dynamic ranges for the detection of BPA, 0.197-2.94 and 3.5-17.72 μM. The regression equation was utilized to determine the sensitivity and limit of detection (LOD), resulting in values of 0.6 μA cm-2 μM-1 and 0.02 μM (S/N = 3), respectively. The kinetics of BPA oxidation at the polyCoRu/GCE were investigated to evaluate the heterogeneous rate constant (k), charge transfer coefficient (α), and the number of electrons transferred during the oxidation and rate-determining step. A probable electrochemical reaction mechanism has been presented for further comprehending the phenomena occurring at the electrode surface. The practical applicability of the fabricated electrode was analyzed using tap water, resulting in a high percentage of recovery ranging from 96 to 105%. Furthermore, the reproducibility and stability data demonstrated the excellent performance of polyCoRu/GCE.

ZnO Hollow Quasi-Spheres Modified Screen-Printed Graphite Electrode for Determination of Carmoisine

Food colorants are important in food selection because they improve the gastronomic appeal of foods by improving their aesthetic appeal. However, after prolonged use, many colorants turn toxic and cause medical problems. A synthetic azo-class dye called carmoisine gives meals a red color. Therefore, the carmoisine determination in food samples is of great importance from the human health control. The current work was developed to synthesis ZnO hollow quasi-spheres (ZnO HQSs) to prepare a new electrochemical carmoisine sensor that is sensitive. Field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) have been used to analyze the properties of prepared ZnO HQSs. A screen-printed graphite electrode (SPGE) surface was modified with ZnO HQSs to prepare the ZnO HQSs-SPGE sensor. For carmoisine detection, the ZnO HQSs-SPGE demonstrated an appropriate response and notable electrocatalytic activities. The carmoisine electro-oxidation signal was significantly stronger on the ZnO HQSs-SPGE surface compared to the bare SPGE. Cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CHA), and differential pulse voltammetry (DPV) have been utilized to investigate the suggested protocol. The DPV results revealed an extensive linear association between variable carmoisine concentrations and peak current that ranged from 0.08 to 190.0 µM, with a limit of detection (LOD) as narrow as 0.02 µM. The ZnO HQSs-SPGE's ability to detect carmoisine in real samples proved the sensor's practical application.

Performance of a dual-chamber microbial fuel cell as a biosensor for in situ monitoring Bisphenol A in wastewater

This research explores the possibilities of a dual-chamber microbial fuel cell as a biosensor to measure Bisphenol A (BPA) in wastewater. BPA is an organic compound and is considered to be an endocrine disruptor, affecting exposed organisms, the environment, and human health. The performance of the microbial fuel cells (MFCs) was first controlled with specific operational conditions (pH, temperature, fuel feeding rate, and organic loading rate) to obtain the best accuracy of the sensor signal. After that, BPA concentrations varying from 50 to 1000 μg L^-1 were examined under the biosensor's cell voltage generation. The outcome illustrates that MFC generates the most power under the best possible conditions of neutral pH, 300 mg L^-1 of COD, R 1000 Ω, and ambient temperature. In general, adding BPA improved the biosensor's cell voltage generation. A slight linear trend between voltage output generation and BPA concentration was observed with R² 0.96, which indicated that BPA in this particular concentration range did not real harm to the MFC's electrogenic bacteria. Scanning electron microscope (SEM) images revealed a better cover biofilm after BPA injection on the surface electrode compared to it without BPA. These results confirmed that electroactive biofilm-based MFCs can serve to detect BPA found in wastewaters.

A state-of-the-art review on the nanomaterial-based sensor for detection of venlafaxine

Venlafaxine (denoted as VFX), a member of the most extensively prescribed antidepressants, is used to handle major depressive disorder, panic disorder and anxiety. This medication affects brain chemistry, which could cause an imbalance in depressed people. VFX and its metabolites, on the other hand, are pollutants in the water environment. Through movement and transformation in several procedures like adsorption, photolysis, hydrolysis and biodegradation, they have harmed living creatures, resulting in the enhancement of diverse active chemicals found in the environment. As a result, determining VFX at modest concentrations with excellent sensitivity, specificity and repeatability are critical. To quantify VFX, various analytical methodologies have been developed. Electroanalytical processes, on the other hand, have piqued interest because of their superior benefits over traditional techniques such as speed, sensitivity, directness and affordability. Subsequently, the purpose of this article is to show how to determine VFX electrochemically using a wide range of electrodes, including CPE, GCE, MCE, SPE, PGE and ISE.

Understanding the endocrine disruptor and determination of bisphenol A by functional Cu-BTABB-MOF/rGO composite as facile rapid electrochemical sensor: an experimental and DFT investigation

A pioneering CuBTABB-MOF/rGO composite customized electrode is fabricated and utilized as a sensor towards identifying bisphenol A (BPA) in a phosphate buffer solution of pH 7.0. The composite is characterized by FTIR, Raman spectroscopy, XRD, SEM, EDX, HRTEM, and XPS to study its structural and morphological properties. Compared with Cu-BTABB-MOF and Cu-BTABB-MOF@GO, the Cu-BTABB-MOF@rGO modified electrode is more sensitive and selective to BPA due to a strong interaction between them. The developed Cu-BTABB-MOF@rGO modified electrode exhibits good sensitivity (6.95 × 10^-5 A mol^-1 L^-1) for BPA having a wide linear range of 0-100 μmol L^-1 with the LOD of 2.08 × 10^-5 mol L^-1, reproducibility of 4.35%, and relative standard deviation (RSD) and stability of 90% for thirty days. In addition, the developed electrocatalyst remained unoccupied from interfering substances and consequently provided an encouraging platform for swift detection of BPA in real samples such as pond water and packed water bottles. Additionally, we utilized DFT (density functional theory) to model GO and Cu-BTABB-MOF structures for detecting BPA molecules.

Recent Advantages of Mediator Based Chemically Modified Electrodes; Powerful Approach in Electroanalytical Chemistry

Background:

Modified electrodes have advanced from the initial studies aimed at understanding electron transfer in films to applications in areas such as energy production and analytical chemistry. This review emphasizes the major classes of modified electrodes with mediators that are being explored for improving analytical methodology. Chemically modified electrodes (CMEs) have been widely used to counter the problems of poor sensitivity and selectivity faced in bare electrodes. We have briefly reviewed the organometallic and organic mediators that have been extensively employed to engineer adapted electrode surfaces for the detection of different compounds. Also, the characteristics of the materials that improve the electrocatalytic activity of the modified surfaces are discussed.

Objective:

Improvement and promotion of pragmatic CMEs have generated a diversity of novel and probable strong detection prospects for electroanalysis. While the capability of handling the chemical nature of the electrode/solution interface accurately and creatively increases , it is predictable that different mediators-based CMEs could be developed with electrocatalytic activity and completely new applications be advanced.

Fabrication of Electrochemical Sensor for Epinine Determination Amplified with MgO/CNTs Nanocomposite and Ionic Liquid

Background:

Catecholamines are a large group of pharmacological and biological compounds that are widely used in biological systems. These compounds are prepared both naturally and synthetically with many key roles in the human body and its activities. Therefore, many researchers focused on the identification and determination of catecholamines in biological samples.

Methods:

MgO/SWCNTs were synthesized through the chemical precipitation method. In addition, cyclic voltammetry, differential pulse voltammetry, and chronoamperometric methods were used for the electro-oxidation reaction study of epinine at the surface of the modified electrode.

Results:

Carbon paste electrode (CPE) modified with MgO/SWCNTs nanocomposite and 1-butyl- 3-methylimidazolium methanesulfonate (BMMS) was used as an electrochemical sensor for the determination of epinine. The results showed a linear dynamic range of 5.0 nM-250 μM with a detection limit of 0.1 nM for epinine determination using MgO/SWCNTs/BMMS/CPE as a sensor.

Conclusion:

In the present study, a highly sensitive electrochemical sensor was designed and fabricated as an analytical tool for the determination of epinine. MgO/SWCNTs/BMMS/CPE was successfully used for the determination of epinine in water and dextrose saline with an acceptable recovery range of 98.7%-102.72%.

Doxorubicin Anticancer Drug Monitoring by ds-DNA-Based Electrochemical Biosensor in Clinical Samples

In this research, glassy carbon electrode (GCE) amplified with single-wall carbon nanotubes (SWCNTs) and ds-DNA was fabricated and utilized for voltammetric sensing of doxorubicin with a low detection limit. In this technique, the reduction in guanine signal of ds-DNA in the presence of doxorubicin (DOX) was chosen as an analytical factor. The molecular docking study revealed that the doxorubicin drug interacted with DNA through intercalation mode, which was in agreement with obtained experimental results. The DOX detection performance of ds-DNA/SWCNTs/GCE was assessed at a concentration range of 1.0 nM-20.0 µM. The detection limit was found to be 0.6 nM that was comparable and even better (in many cases) than that of previous electrochemical reported sensors. In the final step, the ds-DNA/SWCNTs/GCE showed powerful ability for determination of the DOX in injection samples with acceptable recovery data.

Hybrid nanostructures of Pd-WO3 grown on graphitic carbon nitride for trace level electrochemical detection of paraoxon-ethyl

Well-defined crystal structures of Pd-doped WO₃ nanorods were assembled on graphitic carbon sheets (Pd-WO₃/g-C₃N₄) for ultrasensitive detection of paraoxon-ethyl (PEL) using an electrochemical method. The electrochemical behavior of PEL on the Pd-WO₃/g-C₃N₄ hybrid composite was investigated using cyclic voltammetry (CV) and amperometric techniques. The Pd-WO₃ crystallite was seen to modify the kinetics of g-C₃N₄, which improved the reduction/redox peak currents of PEL at the Pd-WO₃/g-C₃N₄ composite compared to those of the g-C₃N₄ and WO₃/g-C₃N₄-modified electrode. Moreover, the π-π interaction and hydrogen bond between the PEL and Pd-WO₃/g-C₃N₄ composite improved the charge-transfer properties. The Pd-WO₃/g-C₃N₄ hybrid composite was therefore able to obtain an enhanced sensitivity (3.70 ± 0.05 μA μM^-1 cm^-2) and low detection limit (0.03 nM; S/N = 3) with a wide range of linear concentrations (0.01-60 and 80-900.0 ± 5 μM) at applied potential of - 0.63 V (vs. Ag/AgCl). The detection of PEL in agricultural water and soil samples was successfully demonstrated with satisfactory RSD of 2.5 to 3.1% and recovery results of 97 to 102%, respectively.

Au@SnO2-vertical graphene-based microneedle sensor for in-situ determination of abscisic acid in plants

For developing electrochemical plant sensors, in-situ detection of hormone levels in living plants is worth attempting. A microneedle array sensor based on Au@SnO₂-vertical graphene (VG)/Ta microelectrodes was constructed for analyzing abscisic acid (ABA) in plants. Graphene was vertically grown on Ta wires with a diameter of 0.6 mm by direct current arc plasma jet chemical vapor deposition with SnO₂ as the Au catalyst carrier. These VG nanosheets were embedded with core-shell Au@SnO₂ nanoparticles, and the formation mechanism of the sensing layer was investigated. Three Au@SnO₂-VG microelectrodes, one Ti wire, and one Pt wire were packed into a microneedle array sensor with a three-electrode system. ABA was then quantitatively detected by direct electrocatalytic oxidation, which involves the synergistic catalytic effects of the abundant catalytic active sites of the Au@SnO₂ nanoparticles and the excellent conductivity of the VG nanosheets. The microneedle array sensor responds to ABA in the pH range 4-7, the response concentration range was 0.012 (or 0.024)-495.2 μM, and the detection limit varied between 0.002 and 0.005 μM. The small size, wide pH range, low detection limit, and wide linear concentration range allow the microneedle array sensor to be inserted into plants for in-situ detection of ABA.

A New Electrochemical Platform for Dasatinib Anticancer Drug Sensing Using Fe3O4-SWCNTs/Ionic Liquid Paste Sensor

A new electrochemical platform was suggested for the sensing of the dasatinib (DA) anticancer drug based on paste electrode modification (PE) amplified with Fe₃O₄-SWCNTs nanocomposite and 1-hexyl-3-methylimidazolium tetrafluoroborate (mim-BF₄⁻). The new platform showed a linear dynamic range from 0.001–220 µM with a detection limit of 0.7 nM to determine DA at optimal condition. Electrochemical investigation showed that the redox reaction of DA is relative to changing the pH of solution. Moreover, Fe₃O₄-SWCNTs/mim-BF₄⁻/PE has improved the oxidation current of DA about 5.58 times which reduced its oxidation potential by about 120 mV at optimal condition. In the final step, Fe₃O₄-SWCNTs/mim-BF₄⁻/PE was used as an analytical platform to determine the DA in tablets and a dextrose saline spike sample, and the results showed recovery data 99.58–103.6% which confirm the powerful ability of the sensor as an analytical tool to determine the DA in real samples.

A sensitive and fast approach for voltammetric analysis of bisphenol a as a toxic compound in food products using a Pt-SWCNTs/ionic liquid modified sensor

A sensitive and fast approach has been introduced for the voltammetric sensing of bisphenol A based on modification of a paste electrode with Pt-SWCNTs and 1-ethyl-3-methylimidazolium n-butylsulfate as a highly conductive binder. The new sensor was used to determine the concentration of bisphenol A in food products in I-V mode. The Pt-SWCNTs nanocomposite was synthesized through the polyol method and its morphology was evaluated by field emission scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy techniques. The determining factors influencing the sensing performance, i.e., pH and mediators used in the modification process were optimized in the first step and the results showed that at a pH of 7.0, a modified paste containing 9% (w:w) nanocomposite and 20% (v:v) 1-ethyl-3-methylimidazolium n-butylsulfate formed catalytic properties enhancing the oxidation signal of bisphenol A by 5.9 folds. Current density investigation clearly confirmed the conductivity of Pt-SWCNTs and 1-ethyl-3-methylimidazolium n-butylsulfate in the paste matrix. In addition, fabricated sensor showed considerable sensing behavior for bisphenol A in the concentration range of 0.5 nM-180 μM with a detection limit of 0.2 nM. In the final step, using standard addition technique, the ability of fabricated sensor for sensing bisphenol A in food products was evaluated, and the results confirmed improved performance of the modified electrodes.

Recent developments in voltammetric and amperometric sensors for cysteine detection

This review article aims to provide an overview of the recent advances in the voltammetric and amperometric sensing of cysteine (Cys). The introduction summarizes the important role of Cys as an essential amino acid, techniques for its sensing, and the utilization of electrochemical methods and chemically modified electrodes for its determination. The main section covers voltammetric and amperometric sensing of Cys based on glassy carbon electrodes, screen printed electrodes, and carbon paste electrodes, modified with various electrocatalytic materials. The conclusion section discusses the current challenges of Cys determination and the future perspectives.

Recent Advances in the Electrochemical Sensing of Venlafaxine: An Antidepressant Drug and Environmental Contaminant

Venlafaxine (VEN), as one of the popular anti-depressants, is widely utilized for the treatment of major depressive disorder, panic disorder, as well as anxiety. This drug influences the chemicals in the brain, which may result in imbalance in depressed individuals. However, venlafaxine and its metabolites are contaminants in water. They have exerted an adverse influence on living organisms through their migration and transformation in various forms of adsorption, photolysis, hydrolysis, and biodegradation followed by the formation of various active compounds in the environment. Hence, it is crucial to determine VEN with low concentrations in high sensitivity, specificity, and reproducibility. Some analytical techniques have been practically designed to quantify VEN. However, electroanalytical procedures have been of interest due to the superior advantages in comparison to conventional techniques, because such methods feature rapidity, simplicity, sensitivity, and affordability. Therefore, this mini-review aims to present the electrochemical determination of VEN with diverse electrodes, such as carbon paste electrodes, glassy carbon electrodes, mercury-based electrodes, screen-printed electrodes, pencil graphite electrodes, and ion-selective electrodes.

Recent Advances in Electrochemical Sensors and Biosensors for Detecting Bisphenol A

In recent years, several studies have focused on environmental pollutants. Bisphenol A (BPA) is one prominent industrial raw material, and its extensive utilization and release into the environment constitute an environmental hazard. BPA is considered as to be an endocrine disruptor which mimics hormones, and has a direct relationship to the development and growth of animal and human reproductive systems. Moreover, intensive exposure to the compound is related to prostate and breast cancer, infertility, obesity, and diabetes. Hence, accurate and reliable determination techniques are crucial for preventing human exposure to BPA. Experts in the field have published general electrochemical procedures for detecting BPA. The present timely review critically evaluates diverse chemically modified electrodes using various substances that have been reported in numerous studies in the recent decade for use in electrochemical sensors and biosensors to detect BPA. Additionally, the essential contributions of these substances for the design of electrochemical sensors are presented. It has been predicted that chemically modified electrode-based sensing systems will be possible options for the monitoring of detrimental pollutants.

Fabrication of magnetic iron oxide-supported copper oxide nanoparticles (Fe3O4/CuO): modified screen-printed electrode for electrochemical studies and detection of desipramine

The present investigation examines a sensitive electrochemical technique to detect desipramine through Fe₃O₄/CuO nanoparticles (NPs). Fe₃O₄/CuO NPs were synthesized via a coprecipitation procedure, and the products were characterized via energy disperse spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and vibrating sample magnetometer. The voltage–current curve and differential pulse voltammetry examinations of Fe₃O₄/CuO-modified screen-printed electrode (Fe₃O₄/CuO/SPE) were followed by the determination of electro-catalytic activities toward desipramine oxidation in a phosphate buffer solution (pH = 7.0). In addition, the value of diffusion coefficient (D = 3.0 × 10⁻⁶ cm² s⁻¹) for desipramine was calculated. Then, based on the optimum conditions, it was observed that the currents of the oxidation peak were linearly proportionate to the concentration of desipramine in the broad range between 0.08 and 400.0 μM and LOD of 0.03 μM (S/N = 3). Finally, our new sensor was successfully utilized to detect desipramine in the real samples, with reasonable recovery in the range of 97.2% to 102.7%.

The present investigation examines a sensitive electrochemical technique to detect desipramine through Fe₃O₄/CuO nanoparticles.