Peroxide Electrochemical Sensor Research Articles

A universal three-dimensional hydrogel electrode for electrochemical detection of SARS-CoV-2 nucleocapsid protein and hydrogen peroxide

Coronavirus disease 2019 (COVID-19) is a highly contagious illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in a global health crisis. The primary diagnostic method for COVID-19 is quantitative reverse transcription PCR, which is time-consuming and requires expensive instrumentation. Here, we developed an electrochemical biosensor for detecting SARS-CoV-2 biomarkers using a 3D porous polyacrylamide/polyaniline hydrogel (PPG) electrode prepared by UV photopolymerization and in situ polymerization. The electrochemical immunosensor for detecting SARS-CoV-2 N protein via the immune sandwich principle demonstrated a lower detection limit of 42 pg/mL and comparable specificity to a commercial enzyme-linked immunosorbent assay, which was additionally validated in pseudoviruses. The electrochemical sensor for hydrogen peroxide showed a low detection limit of 0.5 μM and excellent selectivity, which was further confirmed in cancer cells under oxidative stress. The biomarkers of SARS-CoV-2 were successfully detected due to the signal amplification capability provided by 3D porous electrodes and the high sensitivity of the antigen-antibody specific binding. This study introduces a novel three-dimensional electrode with great potential for the early detection of SARS-CoV-2.

In Situ Performance Monitoring of Electrochemical Oxygen and Hydrogen Peroxide Sensors in an Additively Manufactured Modular Microreactor.

Miniaturized and microstructured reactors in process engineering are essential for a more decentralized, flexible, sustainable, and resilient chemical production. Modern, additive manufacturing methods for metals enable complex reactor-geometries, increased functionality, and faster design iterations, a clear advantage over classical subtractive machining and polymer-based approaches. Integrated microsensors allow online, in situ process monitoring to optimize processes like the direct synthesis of hydrogen peroxide. We developed a modular tube-in-tube membrane reactor fabricated from stainless steel via 3D printing by laser powder bed fusion of metals (PBF-LB/M). The reactor concept enables the spatially separated dosage and resaturation of two gaseous reactants across a membrane into a liquid process medium. Uniquely, we integrated platinum-based electrochemical sensors for the online detection of analytes to reveal the dynamics inside the reactor. An advanced chronoamperometric protocol combined the simultaneous concentration measurement of hydrogen peroxide and oxygen with monitoring of the sensor performance and self-calibration in long-term use. We demonstrated the highly linear and sensitive monitoring of hydrogen peroxide and dissolved oxygen entering the liquid phase through the membrane. Our measurements delivered important real-time insights into the dynamics of the concentrations in the reactor, highlighting the power of electrochemical sensors applied in process engineering. We demonstrated the stable continuous measurement over 1 week and estimated the sensor lifetime for months in the acidic process medium. Our approach combines electrochemical sensors for process monitoring with advanced, additively manufactured stainless steel membrane microreactors, supporting the power of sensor-equipped microreactors as contributors to the paradigm change in process engineering and toward a greener chemistry.

Highly efficient electrochemical detection of H2O2 utilizing an innovative copper porphyrinic nanosheet decorated bismuth metal-organic framework modified electrode.

The ability to detect hydrogen peroxide is important due to the presence in biological systems. Researchers are highly interested in developing efficient electrochemical hydrogen peroxide sensors. Metal-organic frameworks (MOFs) with their composites, an emerging class of porous materials, are ideal candidates for heterogeneous catalysts because of their versatile functionalities. Using a facile solvothermal reaction, we fabricated a 2D Cu-TCPP nanosheet uniformly grown on a 3D Bi-MOF. The process takes advantage of the large surface area and pore volume of the Bi-MOF while maintaining the crystallinity of Bi-BTC when Cu-TCPP is added to the surface. The sensor was fabricated by depositing the Bi-BTC-Cu-TCPP nanocomposites on a glassy carbon electrode to conduct electrochemical measurements such as cyclic voltammetry and electrochemical impedance spectroscopy. Finally, differential pulse voltammetry was utilized to investigate the effect of hydrogen peroxide on the electrochemical activity of Bi-BTC-Cu-TCPP deposited on a glassy carbon electrode. This electrode showed high electrochemical performance activity for the reduction of hydrogen peroxide. The sensor showed a linear response to H2O2 in the 10-120 μM concentration range, with a detection limit of 0.20 μM. The sensor was also stable and selective for H2O2 in the presence of other interfering species. This work demonstrates the potential of nanocomposite-based electrochemical sensors for sensitive and selective detection of H2O2. Besides, the modified electrode has many advantages, including remarkable catalytic activity, long-term stability, good reproducibility, and a good signal response during H2O2 reduction.

Hydrogen peroxide sensing with nitrogen-doped carbon nanowalls

The fabrication of miniaturized, low-cost, enzyme-free sensors based on nanomaterials via high-performance techniques is expected to provide important benefits for applications in biological detection. In this work, nitrogen-doped carbon nanowalls (CNWs) were synthesized and used to fabricate electrochemical sensor for hydrogen peroxide (H2O2) sensing. The CNWs were grown on Ti\\SiO2\\Si substrates by radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) method with different nitrogen concentration. Structural and morphological properties of the obtained CNWs were analyzed using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron microscopy. Cyclic voltammetry and chronoamperometry were used to analyze the electrochemical properties of N-doped CNWs. This study demonstrates the effectiveness of CNWs doping with nitrogen during the synthesis process to improve the electrochemical characteristics of the sensor. It was shown that CNWs doped at high nitrogen flow rate (N2: 20 sccm) exhibited the highest amperometric response. Cyclic voltammetry results indicate that the CNWs doped at high nitrogen flow rate demonstrate excellent electrochemical activity for the reduction of H2O2. These results could pave the way for the development of easy-to-manufacture and highly efficient metal-free biosensors for H2O2 detection.

Hydrogen Peroxide Electrochemical Sensor Based on Ag/Cu Bimetallic Nanoparticles Modified on Polypyrrole.

Due to the strong oxidizing properties of H2O2, excessive discharge of H2O2 will cause great harm to the environment. Moreover, H2O2 is also an energetic material used as fuel, with specific attention given to its safety. Therefore, it is of great importance to explore and prepare good sensitive materials for the detection of H2O2 with a low detection limit and high selectivity. In this work, a kind of hydrogen peroxide electrochemical sensor has been fabricated. That is, polypyrrole (PPy) has been electropolymerized on the glass carbon electrode (GCE), and then Ag and Cu nanoparticles are modified together on the surface of polypyrrole by electrodeposition. SEM analysis shows that Cu and Ag nanoparticles are uniformly deposited on the surface of PPy. Electrochemical characterization results display that the sensor has a good response to H2O2 with two linear intervals. The first linear range is 0.1-1 mM (R2 = 0.9978, S = 265.06 μA/ (mM × cm2)), and the detection limit is 0.027 μM (S/N = 3). The second linear range is 1-35 mM (R2 = 0.9969, 445.78 μA/ (mM × cm2)), corresponding to 0.063 μM of detection limit (S/N = 3). The sensor reveals good reproducibility (σ = 2.104), repeatability (σ = 2.027), anti-interference, and stability. The recoveries of the electrode are 99.84-103.00% (for 0.1-1 mM of linear range) and 98.65-104.80% (for 1-35 mM linear range). Furthermore, the costs of the hydrogen peroxide electrochemical sensor proposed in this work are reduced largely by using non-precious metals without degradation of the sensing performance of H2O2. This study provides a facile way to develop nanocomposite electrochemical sensors.

Cheap and Mass-Producible Electrochemical Sensor of Hydrogen Peroxide

Abstract Hydrogen peroxide is present naturally in any living cell. Although hydrogen peroxide concentration in cell is strictly regulated during normal metabolism, several human diseases lead to increased hydrogen peroxide concentration in body fluids. It is beneficial to monitor hydrogen peroxide levels in human body for early disease diagnostics. This can be done by creation of electronic device, which will use electrochemical sensor in order to perform automated hydrogen peroxide concentration measurement in a sample. The aim of the research is to use printed circuit board (PCB) technology in order to create a replaceable electrochemical hydrogen peroxide sensor that could be cheaply mass-produced to enable further development of automated health diagnostics device.

Ru doping induced lattice distortion of Cu nanoparticles for boosting electrochemical nonenzymatic hydrogen peroxide sensing

In this paper, we report a new strategy to activate the electrocatalytic activity of Cu to realize the non-enzymatic detection of hydrogen peroxide. The Ru-doped copper nanoparticles were prepared on the surface of carbon materials by direct pyrolysis of Ru in exchange for Cu-BTC metal-organic framework. The materials were characterized by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD). Surprisingly, Ru doping induced obvious lattice distortion of Cu nanoparticles, which made Cu nanoparticles exhibit excellent electrocatalytic activity for hydrogen peroxide reduction. The sensor based on Ru-doped Cu nanoparticles can detect hydrogen peroxide in a wide linear range from 0.01 mM to 5.55 mM. Moreover, as a hydrogen peroxide sensor, it has a high sensitivity of 327.14 µA·mM−1·cm−2 and a low detection limit of 8.9 µM. Therefore, Cu nanoparticles with the lattice distortion was demonstrated to be a potential material for hydrogen peroxide electrochemical sensor.

Highly Efficient Sensing of Hydrogen Peroxide Based on Atomically Dispersed Iron- and Nitrogen-Doped Carbon

Electrochemical hydrogen peroxide (H2O2) sensors are valuable tools in biological research and industrial applications for in situ monitoring H2O2 levels with the advantages of simplicity, portability, rapid response, and low cost. Herein, we demonstrate a novel electrochemical sensing platform based on Fe- and N-doped C composite (Fe–N–C) modified electrodes for sensitive detection of H2O2. This platform showed an excellent response to H2O2 reduction in near-neutral pH solutions with a low reduction potential and high sensitivities. The results of site-poisoning experiments suggest that the atomically dispersed Fe–Nx sites, which resemble the peroxidase-type enzymes, contribute to the high activity of the Fe-N-C catalyst for the H2O2 reduction reaction. Further, we developed a screen-printed electrode (SPE) modified with Fe–N–C with excellent electrocatalytic performances, including a favorable sensitivity (24.95 ± 0.77 μA μM−1 cm−2) and a low detection reagent (40 μl solution). Moreover, the as-prepared Fe–N–C/SPE was successfully applied to H2O2 sensing in an actual milk sample, with good recovery (between 98% and 102%). The as-prepared Fe–N–C/SPE sensor also exhibits superior selectivity, stability, and reproducibility, making it a promising candidate as a portable platform for H2O2 analytes, further improving its practical H2O2 sensing applications.

Cu single-atom catalyst-based flexible hydrogen peroxide electrochemical sensor with oxygen resistance for monitoring ROS bursts.

The study of cellular responses linked to oxidative stress mechanisms is crucial in comprehending diverse physiological and pathological life processes, including mitochondrial dysfunction. Nonetheless, despite the interference of O2, the monitoring of ROS released from cells poses a challenging task. In this study, carbon-based copper single-atom catalysts (Cu SACs) were synthesized that exhibits excellent electrocatalytic performance for H2O2 reduction with an initial potential at 0.23 V and effectively avoids interference from O2. Based on this catalyst, a flexible and stretchable oxygen-tolerant sensor was constructed and applied to monitor the calcium ion-induced ROS burst in human umbilical vein endothelial cells (HUVECs) in a simulated physiological condition. This study effectively eradicates interference that may arise from the reduction of O2 and presents a dependable platform for real-time in situ monitoring of physiologically active molecules by utilizing H2O2 detection.

Ultrasensitive hydrogen peroxide electrochemical sensor based on dual-phase perovskite oxide tubular nanofiber

Dual-phase La0.9Sr0.1NiO3 tubular perovskite oxides exhibit excellent electrochemical performance for H2O2 detection with a wide linear response range of 1–7000 μM, fast response time (t = 0.9 s), good selectivity, and admirable long-term stability.

Bio-Nanohybrid Gelatin/Quantum Dots for Cellular Imaging and Biosensing Applications.

The bio-nanohybrid gelatin protein/cadmium sulfide (Gel/CdS) quantum dots (QDs) have been designed via a facile one-pot strategy. The amino acids group of gelatin chelate Cd2+ and grow CdS QDs without any agglomeration. The 1H NMR spectra indicate that during the above process there are no alterations of the gelatin protein structure conformation and chemical functionalities. The prepared Gel/CdS QDs were characterized and their potential as a system for cellular imaging and the electrochemical sensor for hydrogen peroxide (H2O2) detection applications were investigated. The obtained results demonstrate that the developed Gel/CdS QDs system could offer a simple and convenient operating strategy both for the class of contrast agents for cell labeling and electrochemical sensors purposes.

Electrochemical Sensor for Hydrogen Peroxide Based on Prussian Blue Electrochemically Deposited at the TiO2-ZrO2-Doped Carbon Nanotube Glassy Carbon-Modified Electrode.

In this investigation, a hydrogen peroxide (H2O2) electrochemical sensor was evaluated. Prussian blue (PB) was electrodeposited at a glassy carbon (GC) electrode modified with titanium dioxide– and zirconia-doped functionalized carbon nanotubes (TiO2.ZrO2-fCNTs), obtaining the PB/TiO2.ZrO2-fCNTs/GC-modified electrode. The morphology and structure of the nanostructured material TiO2.ZrO2-fCNTs was characterized by transmission electron microscopy, the specific surface area was determined via Brunauer–Emmett–Teller, X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The electrochemical properties were studied by cyclic voltammetry and chronoamperometry. Titania-zirconia nanoparticles (5.0 ± 2.0 nm) with an amorphous structure were directly synthesized on the fCNT walls, aged during periods of 20 days, obtaining a well-dispersed distribution with a high surface area. The results indicated that the TiO2.ZrO2-fCNT–nanostructured material exhibits good electrochemical properties and could be tunable by enhancing the modification conditions and method of synthesis. Covering of the nanotubes with TiO2-ZrO2 nanoparticles is one of the main factors that affected immobilization and sensitivity of the electrochemical biosensor. The electrode modified with TiO2-ZrO2 nanoparticles with the 20-day aging time was superior regarding its reversibility, electric communication, and high sensitivity and improves the immobilization of the PB at the electrode. The fabricated sensor was used in the detection of H2O2 in whey milk samples, presenting a linear relationship from 100 to 1,000 μmol L−1 between H2O2 concentration and the peak current, with a quantification limit (LQ) of 59.78 μmol L−1 and a detection limit (LD) of 17.93 μmol L−1.

High-performance non-enzymatic hydrogen peroxide electrochemical sensor prepared with a magnetite-loaded carbon nanotube waterborne ink

• Magnetite-loaded carbon nanotube waterborne ink with peroxidase-like activity. • Mechanical stability allowing determinations in forced convection/quiescent conditions. • Ease of preparation, suitable for inkjet and screen-printing methods. • Remarkable analytical figures of merit towards the detection of hydrogen peroxide. • Composite’s formulation optimized to maximize its catalytic properties. In this study, a non-enzymatic hydrogen peroxide sensor was developed employing a waterborne carbon nanotube ink containing catalytic submicrometric particles of magnetite. Magnetite particles were synthesized via a solvothermal method and characterized by scanning electron microscopy (SEM) and powder X-ray diffraction measurements (XRD). For the ink preparation, Fe 3 O 4 particles were incorporated into a waterborne carbon nanotube ink and the mixture was drop casted onto a glassy carbon and used for coating Valox TM strips to fabricate standalone electrodes. As a non-enzymatic amperometric sensor, the resulting Fe 3 O 4 /CNT ink coated electrodes exhibited high-performance values towards the detection of H 2 O 2 , presenting a limit of detection of 0.5 µM, a linear detection range up to 2 mM, a sensitivity of 1040 µA cm −2 mM −1 and tolerance to common interfering agents like ascorbic acid, glucose and Cl - /SO4 -2 ions. Moreover, the Fe 3 O 4 /CNT electrodes presented a high stability, losing only 20% of their catalytic performance after three weeks.

Development of carbon-based metal free electrochemical sensor for hydrogen peroxide by surface modification of carbon nanowalls

A novel metal-free amperometric sensor based on O2/Ar plasma modified carbon nanowalls (CNW) was successfully developed for non-enzymatic detection of hydrogen peroxide (H2O2).This study demonstrates the effectiveness of surface modification of CNW by O2/Ar plasma treatment to improve the electrochemical sensing performance. It was shown that the CNW treated in low oxygen flow rate (O2/Ar: 0.1/10sccm) exhibited the highest concentration of incorporated oxygen on its structure, which consequently resulted in conversion of intrinsic hydrophobicity of CNW to hydrophilicity. Interestingly, however, further increase in oxygen flow rate did not increase the oxygen content of CNW structure, but instead it resulted in an increment in the defect and contributing less oxygen on CNW surface. The highest amperometric response was observed for the CNW treated with O2/Ar: 1.0/10sccm, which has lower oxygen content than the CNW treated with O2/Ar: 0.1/10sccm, but still possessing hydrophilic characteristic as well as owning more defect sites. These results can suggest the importance of both defects and oxygen-containing functional groups in electrochemical behavior of the electrode as both defects and oxygen-containing functional groups can act as potential active sites for electrochemical reactions and oxygen-containing functional groups can enhance the hydrophilicity and surface area wetted by the electrolyte. The modified CNW exhibited the potential for quantification analysis of H2O2 with a wide linear range covering from 50 μM to 28000 μM, a good sensitivity of 126.6 μA/mM.cm2 and a detection limit of 0.91 μM (S/N = 3). This study demonstrates the success in utilizing the CNW structure towards detecting of H2O2 as a metal-free sensor.

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures.

This article describes the synthesis of nanostructured copper oxide on copper wires and its application for the detection of hydrogen peroxide. Copper oxide petal nanostructures were obtained by a one-step hydrothermal oxidation method. The resulting coating is uniform and dense and shows good adhesion to the wire surface. Structure, surface, and composition of the obtained samples were studied using field-emission scanning electron microscopy along with energy-dispersive spectroscopy and X-ray diffractometry. The resulting nanostructured samples were used for electrochemical determination of the H2O2 content in a 0.1 M NaOH buffer solution using cyclic voltammetry, differential pulse voltammetry, and i–t measurements. A good linear relationship between the peak current and the concentration of H2O2 in the range from 10 to 1800 μM was obtained. The sensitivity of the obtained CuO electrode is 439.19 μA·mM−1. The calculated limit of detection is 1.34 μM, assuming a signal-to-noise ratio of 3. The investigation of the system for sensitivity to interference showed that the most common interfering substances, that is, ascorbic acid, uric acid, dopamine, NaCl, glucose, and acetaminophen, do not affect the electrochemical response. The real milk sample test showed a high recovery rate (more than 95%). According to the obtained results, this sensor is suitable for practical use for the qualitative detection of H2O2 in real samples, as well as for the quantitative determination of its concentration.

Facile synthesis of Cu@Cu2O aerogel for an effective electrochemical hydrogen peroxide sensor

Herein, a facile one-step reduction method was used to synthesize Cu@Cu 2 O aerogel to fabricate an electrochemical sensor for detection of hydrogen peroxide. Advanced techniques including X-ray powder diffractions (XRD), transmission electron micrographs (TEMs), field-emission scanning electron microscopy (FESEM) were utilized to characterize the structure of Cu@Cu 2 O aerogel. The results showed that the Cu@Cu 2 O aerogel is composed of Cu and Cu 2 O nanoparticles with a three-dimensional porous structure. The chronoamperometry method was implemented to evaluate the electrochemical performance of Cu@Cu 2 O/GCE (GCE=glassy carbon electrode) towards H 2 O 2 . Under optimal conditions, Cu@Cu 2 O/GCE showed a wide detection range (2∼860 μmol), a low detection limit (0.46 μM, S/ N = 3), a sensitivity of 1855.53 mA M − 1 cm −2 and a good selectivity. In addition, the electrochemical sensor based on Cu@Cu 2 O aerogel can be used for the determination of hydrogen peroxide in watery samples. .

Comparative of MIL101(Cr) and nano‐MIL101(Cr) Electrode as an Electrochemical Hydrogen Peroxide Sensor

AbstractHerein, an electrochemical sensor for the detection of H2O2 based on nafion glassy carbon electrode modified with MIL101(Cr) and nano‐MIL101(Cr) are developed and its electrochemical characterizations analyzed by CV and CA. In comparison with the NGCE, MIL101/NGCE and nano‐MIL101/NGCE, the nano‐MIL101/NGCE showed a sharp redox peak specific to H2O2 was obtained in the phosphate‐calibrated solution. nano‐MIL101/NGCE exhibited good linear response in terms of the relationship between peak currents and concentrations as from 0 to 650 μM (R2=0.99), with a low limit of detection 3.8 μM, high sensitivity 986 μA mM−1 cm−2 and nano‐MIL101/NGCE exhibited ideal repeatability, reproducibility, stability and the interference‐free perception of H2O2.

Three-dimensional loofah sponge derived amorphous carbon-graphene aerogel via one-pot synthesis for high-performance electrochemical sensor for hydrogen peroxide and dopamine

In this work, three-dimensional structured loofah sponge derived amorphous carbon-graphene aerogel (LSDC-GA) was firstly synthesized via one pot hydrothermal method. Graphene nanosheets are connected with each other to form a 3D porous structure, while LSDC nanosheets are randomly embedded between graphene layers without aggregation. Compared with GA and LSDC, LSDC-GA has the largest specific surface area of about 526.4 m2·g−1. The C and O elements of the hybrid LSDC-GA material are originating from reduced GO and LSDC, and the C/O atomic ratio was decreased in the order of LSDC > LSDC-GA > GA. LSDC-GA exhibits the smallest Rct value corresponding to 98.5 Ω, indicative of the excellent electrical conductivity. When applied in the electrochemical detection of hydrogen peroxide (H2O2), the so-formed LSDC-GA electrode shows enhanced sensing properties with high sensitivity, a linear electrochemical range from 12 μM to 2.69 mM, a low detection limit of 1.2 µM, and satisfied selectivity, stability and reproducibility as well. Furthermore, for electrochemical biosensor application of dopamine (DA) detection, the LSDC-GA material also exhibits a linear electrochemical range of 2.5 μM–560 μM and a low limit down to 0.25 μM. These improved sensing performances enable it as promising electrode material for extensive electrochemical sensing applications.

One-step synthesis of crumpled graphene fully decorated by copper-based nanoparticles: Application in H2O2 sensing

The production of 3D graphene-based materials is an alternative to retain the intrinsic properties of 2D graphene, and improve others like specific surface area, porosity, mechanical properties, etc. For practical applications such as electrochemical sensors, the production of electroactive 3D graphene-based composites in one single step with good processability and electrochemical response is extremely desirable. Here, we synthesize 3D composites of crumpled graphene (CG) decorated by copper-based nanoparticles in dry state form without further steps. The aerosol-assisted capillary compression strategy adopted results in copper-based nanoparticles directly connected to CG. The carbon nanostructure controls the nucleation and growth of nanoparticles during capillary compression. We explored the application of the composites as an electrochemical sensor for hydrogen peroxide, and it connects the best performance to the synergism between crumpled graphene and the copper-based nanoparticles.

Organic–inorganic hybrid phosphite-participating S-shaped penta-CeIII-incorporated tellurotungstate as an electrochemical enzymatic hydrogen peroxide sensor for β-d-glucose detection

An organic–inorganic hybrid phosphite-participating S-shaped penta-CeIII-incorporated tellurotungstate was synthesized and used as an electrochemical enzymatic hydrogen peroxide sensor for β-d-glucose detection.