Electrochemical Detection Of H2O2 Research Articles

One-Pot Synthesis of Nanoflower-Like Zn2SnS4 as Nanozymes for Highly Sensitive Electrochemical Detection of H2O2 Released by Living Cells.

The sensitive and reliable nanozyme-based sensor enables the detection of low concentrations of H2O2 in biological microenvironments, it has potential applications as an in-situ monitoring platform for cellular H2O2 release. The uniformly dispersed bimetallic sulfide (Zn2SnS4) nanoflowers were synthesized via a one-pot hydrothermal method and the two kinds of metal ions can serve as morphology and structure directing agents for each other in the synthetic process. The nanoparticles were utilized as nanozyme materials to fabricate a novel electrochemical sensor, and it exhibits a distinct electrochemical response towards H2O2 with excellent stability and detection capability (with a minimum detection limit of 1.79 nM (S/N=3)), the excellent characteristics facilitate the precise detection of low concentrations of H2O2 in biological microenvironments. Use the macrophages differentiated from leukemia THP-1 cells as a representative sensing model, the sensor was successfully utilized for real-time monitoring of the release of H2O2 induced by living cells, which has significant potential applications in clinical diagnosis and cancer treatment.

Flexible Co-Ni nanocomposites in situ synthesized on carbon fibers for highly sensitive electrochemical detection of H2O2

In this study, Co-Ni nanomaterials were in situ synthesized on carbon fiber paper substrates, termed Co-Ni paper. Scanning electron microscopy characterization demonstrates fabricated flake-like Co-Ni nanocomposites uniformly distribute on carbon fibers, forming three-dimensional continuous network structure. The fabricated sample is determined to be a mixture of Co, Ni and C elements according to energy-dispersive X-ray spectrometer analysis. Without any pretreatments, Co-Ni paper exhibits excellent electro-oxidation capabilities towards H2O2, such as an excellent detecting performance in a wide linear range of 0‒11.5 mM of H2O2, fast amperometric responses within 1 s, and a low detection limit of 2.53 μM. Along with these intriguing properties, the in situ-synthesized Co-Ni paper has a good anti-interference towards Na2SO4, ZnCl2, glucose and NaCl during H2O2 detection. Moreover, the H2O2 electro-chemical sensor on Co-Ni paper also possesses excellent reproducibility, long-term stability and high mechanical stability. This Co-Ni-paper-based sensor is effective to determine H2O2 in blood samples, thus it is promising for electrochemical H2O2 sensing.

Graphene supported gold hollow sphere for real-time electrochemical detection of H2O2 released from cells

In this work, graphene undergoes twice oxidization to produce reoxidized-graphene oxide (ROGO), and then ROGO reacts with thiourea to obtain thiol-functionalized reduced ROGO (rROGO-SH), achieving reduction and surface thiolation. Subsequently, Au hollow spheres (Au HS) are decorated on rROGO-SH, and an electrochemical sensor is therefore fabricated by coating rROGO-S-Au HS on a glassy carbon electrode (GCE). rROGO-S-Au HS/GCE exhibits attractive electrochemical performance for H2O2 detection with a wide linear detection range (5 μM to 11.5 mM), low detection limit (5 μM), and good sensitivity (0.19 mA mM−1 cm−2). Due to its good performance for in-vivo detection, rROGO-S-Au HS/GCE can sensitively detect a trace amount of H2O2 released from living tumor cells. Hence, the rROGO-S-Au HS based electrochemical sensing platform shows great potential for online monitoring of H2O2 levels at tumor sites, which is beneficial for the rapid and sensitive diagnosis of cancer, as well as in vivo monitoring of tumor progression.

Synergism of Holmium Orthovanadate/Phosphorus-Doped Carbon Nitride Nanocomposite: Nonenzymatic Electrochemical Detection of Hydrogen Peroxide.

Developing efficient and robust electrode materials for electrochemical sensors is critical for real-time analysis. In this paper, a hierarchical holmium vanadate/phosphorus-doped graphitic carbon nitride (HoVO4/P-CN) nanocomposite is synthesized and used as an electrode material for electrochemical detection of hydrogen peroxide (H2O2). The HoVO4/P-CN nanocomposite exhibits superior electrocatalytic activity at a peak potential of -0.412 V toward H2O2 reduction in alkaline electrolytes while compared with other reported electrocatalysts. The HoVO4/P-CN electrochemical platform operated under the optimized conditions shows excellent analytical performance for H2O2 detection with a linear concentration range of 0.009-77.4 μM, a high sensitivity of 0.72 μA μM-1 cm-2, and a low detection limit of 3.0 nΜ. Furthermore, the HoVO4/P-CN-modified electrode exhibits high selectivity, remarkable stability, good repeatability, and satisfactory reproducibility in detecting H2O2. Its superior performance can be attributed to a large specific surface area, high conductivity, more active surface sites, unique structure, and synergistic action of HoVO4 and P-CN to benefit enhanced electrochemical activity. The proposed HoVO4/P-CN electrochemical platform is effectively applied to ascertain the quantity of H2O2 in food and biological samples. This work outlines a promising and effectual strategy for the sensitive electrochemical detection of H2O2 in real-world samples.

Advances in Non-Enzymatic electrochemical materials for H2O2 sensing

With the progression of society, an increasing emphasis on physical well-being and environmental safety has driven extensive research into technologies closely aligned with human health and environmental protection. Hydrogen peroxide (H2O2), a representative reactive oxygen species (ROS), serves as one of the products resulting from the single electron reduction of oxygen in organisms, playing a crucial role in cell signaling and maintaining internal stability. Relevant alterations of H2O2 concentrations have been implicated in the pathogenesis of various diseases, including diabetes and cancer. Moreover, the utilization of H2O2 is widely prevalent in various industries including chemical, pharmaceutical, and food sectors. However, the repetitive or uncontrolled utilization of H2O2 engenders deleterious implications for human well-being and environmental integrity. Therefore, there is immense significance in exploring a simple yet effective method for real-time and quantitative detection of H2O2 in living cells and actual samples. The use of nanocatalysts as sensing materials in the electrochemical detection method has garnered significant attention from researchers due to their operational simplicity, high sensitivity, cost-effectiveness, and facile miniaturization. However, there remains a dearth of comprehensive reviews on the electrochemical detection of H2O2 utilizing nanomaterials. In this paper, we focus on summarizing contemporary techniques for H2O2 detection with a specific emphasis on electrochemical detection methods, and highlighting the significant advancements in the field of electrochemical detection of H2O2 nanomaterials while also providing insights into future developments.

Coupling metal organic frameworks nanozyme with carbon nanotubes on the gradient porous hollow fiber membrane for nonenzymatic electrochemical H2O2 detection

In this paper, we present a gradient porous hollow fiber structure integrated the signal transduction within a microspace, serving as a platform for cellular metabolism monitoring. We developed a nonenzymatic electrochemical electrode by coupling carbon nanotubes (CNT) and metal organic frameworks (MOF) nanozyme on three-dimensional (3D) gradient porous hollow fiber membrane (GPF) for in-situ detection of cell released hydrogen peroxide (H2O2). The GPF was used as a substrate for cell culture as well as the supporting matrix of the working electrode. The ultrasonically coupled CNT@MOF composite was immobilized on the outer surface of the GPF by means of pressure filtration. Notably, the MOF, acting as a peroxidase mimic, exhibits superior stability compared to traditional horseradish peroxidase. The incorporation of CNT not only provided sufficient specific surface area to improve the uniform distribution of MOF nanozyme, but also formed 3D conductive network. This network efficiently facilitates the electrons transfer during the catalytic process of the MOF, addressing the inherent poor conductivity of MOFs. The GPF-CNT@MOF nonenzymatic bioelectrode demonstrated excellent electrocatalytic performance including rapid response, satisfactory sensing selectivity, and attractive stability, which enabled the development of a robust in-situ cellular metabolic monitoring platform.

Self-assembly of Copper Nanoclusters Using DNA Nanoribbon Templates for Sensitive Electrochemical Detection of H2O2 in Live Cells

The excessive secretion of H2O2 within cells is closely associated with cellular dysfunction. Therefore, high sensitivity in situ detection of H2O2 released from living cells was valuable in clinical diagnosis. In the present work, a novel electrochemical cells sensing platform by synthesizing copper nanoclusters (CuNCs) at room temperature based on DNA nanoribbon (DNR) as a template (DNR-CuNCs). The tight and ordered arrangement of nanostructured assemblies of DNR-CuNCs conferred the sensor with superior stability (45 days) and electrochemical performance. The MUC1 aptamer extending from the DNR template enabled the direct capture MCF-7 cells on electrode surface, this facilitated real-time monitoring of H2O2 release from stimulated MCF-7 cells. While the captured MCF-7 cells on the electrode surface significantly amplified the current signal of H2O2 release compared with the traditional electrochemical detection H2O2 released signal by MCF-7 cells in PBS solution. The approach provides an effective strategy for the design of versatile sensors and achieving monitored cell release of H2O2 in long time horizon (10 h). Thereby expanding the possibilities for detecting biomolecules from live cells in clinical diagnosis and biomedical applications.

Prudently designed Se@fMWCNT as a peroxidase mimicking nanozyme for distinctive electrochemical detection of H2O2 and glutathione

A Se@fMWCNT nanocomposite with peroxidase mimicking activity was used for the electrochemical detection of H2O2 and glutathione. Both analytes were detected using amperometry at a low potential of −0.2 V, with excellent selectivity and sensitivity.

Facile fabrication of HRP-Cu3(PO4)2 hybrid nanoflowers on screen-printed electrode for electrochemical detection of H2O2

H2O2 sensor is widely used in biomedicine, environmental governance and food processing. However, it is limited by the complex preparation processes and high cost of raw materials. In this work, we develop a facile, simple and cost-effective method to fabricate H2O2 sensor based on a screen-printed electrode via in-situ growth method. The copper was first electrodeposited on the working electrode of screen-printed electrode (SPE) as a sacrificial layer, subsequently, the SPE was immersed in horseradish peroxidase (HRP) containing phosphate buffer saline (PBS). The Cu ions formed by oxidation of the copper layer combined with HRP and phosphate ions to construct HRP-Cu3(PO4)2 hybrid nanoflowers on its surface. The fabrication process is straightforward, without complex reaction conditions and dangerous drugs, which is conducive to mass production. This sensor showed a good linear response to H2O2 with a detection limit of 1.8 μM and a sensitivity of 263.3 μA∙mM−1∙cm−2. Additionally, it possessed excellent selectivity and long-time stability. The performance of this sensor was investigated in various beverages such as milk, beer, and juice, showing reliable detection of H2O2 which highlights the potential practical applications of the sensor.

Metal-organic framework-derived leaf-like and stick-like Co3O4 for electrochemical sensing of H2O2

Developing electrochemical H2O2 sensors with high sensitivity and selectivity is highly desirable in the food industry. Low-dimensional transition metal oxides are promising in electrochemical sensing due to their attractive characteristics. In this study, leaf-like zeolitic imidazolate framework (ZIF-L) and stick-like zeolitic imidazolate framework (ZIF-S) were used to prepare leaf-shaped L-Co3O4 (L-Co3O4) and stick-shaped Co3O4 (S-Co3O4). The low-dimensional structure could shorten the electron transmission paths and expose more active sites. A series of characterizations were carried out to investigate the morphology and composition of these two materials. Further, the L-Co3O4 and S-Co3O4 were investigated for electrochemical H2O2 detection. The L-Co3O4 showed good electrocatalytic activity toward H2O2 in the ranges of 0.5–4500 and 4500–10000 μM with a detection limit of 0.47 μM. Moreover, the S-Co3O4 had good H2O2 detection performance in the ranges of 0.5–4500 and 4500–10000 μM with a detection limit of 0.33 μM. The constructed sensors also showed good anti-interference ability, reproducibility, stability, and applicability.

Highly Conductive Peroxidase-like Ce-MoS2 Nanoflowers for the Simultaneous Electrochemical Detection of Dopamine and Epinephrine.

The accurate and simultaneous detection of neurotransmitters, such as dopamine (DA) and epinephrine (EP), is of paramount importance in clinical diagnostic fields. Herein, we developed cerium-molybdenum disulfide nanoflowers (Ce-MoS2 NFs) using a simple one-pot hydrothermal method and demonstrated that they are highly conductive and exhibit significant peroxidase-mimicking activity, which was applied for the simultaneous electrochemical detection of DA and EP. Ce-MoS2 NFs showed a unique structure, comprising MoS2 NFs with divalent Ce ions. This structural design imparted a significantly enlarged surface area of 220.5 m2 g-1 with abundant active sites as well as enhanced redox properties, facilitating electron transfer and peroxidase-like catalytic action compared with bare MoS2 NFs without Ce incorporation. Based on these beneficial features, Ce-MoS2 NFs were incorporated onto a screen-printed electrode (Ce-MoS2 NFs/SPE), enabling the electrochemical detection of H2O2 based on their peroxidase-like activity. Ce-MoS2 NFs/SPE biosensors also showed distinct electrocatalytic oxidation characteristics for DA and EP, consequently yielding the highly selective, sensitive, and simultaneous detection of target DA and EP. Dynamic linear ranges for both DA and EP were determined to be 0.05~100 μM, with detection limits (S/N = 3) of 28 nM and 44 nM, respectively. This study shows the potential of hierarchically structured Ce-incorporated MoS2 NFs to enhance the detection performances of electrochemical biosensors, thus enabling extensive applications in healthcare, diagnostics, and environmental monitoring.

Hierarchical confinement of Prussian blue nanoparticles via NH2-MIL-88B(Fe): Rational design and electrocatalytic application

The design of Prussian blue nanoparticles (PB NPs) with satisfied electrocatalytic ability and stability is still challenging. Herein, a hierarchical confinement strategy of PB NPs is proposed using NH2MIL-88B(Fe) (denoted herein as NH2MIL) as both self-confined template and Fe3+ sources, K3[Fe(CN)3] as precursor. The catalytic synthesis of PB NPs is further achieved during the hydrothermal process at 100 °C for 1 h. The as-prepared PB@NH2MIL exhibits the morphology of “sea cucumber”, retaining the intrinsic skeleton of NH2MIL dotted with lots of PB NPs (<40 nm). In addition, the initial coordination of [Fe(CN)3]3- with the active free coordination sites of NH2MIL results in the coatom phenomenon between NH2MIL and PB NPs. Thus, the as-prepared PB@NH2MIL possesses the efficient electronic transmission, the enhanced electrocatalytic properties as well as stability under prolonged electrochemical measurements. Finally, the as-prepared PB@NH2MIL can be used as artificial peroxidase for the electrochemical detection of H2O2 with a wider linear range (0.01–1000 μM) and low detection limit (3 nM).

Fabrication of Hydroxyl‐Group‐Rich Reduced Graphene Oxide Film and its Application for Electrochemical Detection of Hydrogen Peroxide

AbstractGraphene oxide (GO) can be obtained economically from graphite, and it has, therefore, been used for energy storage, conversion, and biosensor fabrication. To overcome the limitations associated with the poor electrical conductivity of GO, mild thermal reduction is widely used. However, owing to considerable variations in GO in terms of size and shape, uniform reduction of GO films is highly challenging. Herein, it reports a mildly reduced uniform graphene oxide thin film (mrUG) that is enriched with functional hydroxyl groups. This film is effective for electrochemical H2O2 decomposition and detection. A uniform graphene oxide thin film (UGTF) is first fabricated on an indium tin oxide (ITO) substrate and subjected to mild thermal annealing at 300 °C. Remarkably, the variations in all important parameters, including film thickness, surface roughness, reduction level, are significantly low in the case of mrUG. Moreover, It is found that unlike GO, UGTF undergoes structural rearrangement easily and possesses many hydroxyl groups (─OH) when reduced for a specific duration (t = 10 s, mrUG(10)). mrUG(10) is highly stable and effectively decomposed H2O2, which is advantageous for the electrochemical detection of H2O2 with extremely low signal variations. Therefore, mrUG(10) can be used as a carbon‐based metal‐free electrocatalyst in biosensors, energy, and electronic applications.

A novel sensor based on P-Ru/NC for sensitive electrochemical detection of H2O2

The reasonable design and construction of electrocatalytic nanomaterial is crucial to improve the performance of non-enzymatic electrochemical sensors. Here, P-Ru/NC nanocomposite was synthesized for boosting electrochemical H2O2 sensing. The anchoring of ruthenium nanoparticles (Ru NP) and the doping of P are achieved by one-step pyrolysis. The synergistic effect between Ru NP and P doping made P-Ru/NC possess larger electrochemical surface area, rich active sites and fast electron transfer rate. The electrochemical results reveal that P-Ru/NC/GCE shows higher electrocatalytic activity toward H2O2 than Ru/NC/GCE and P-NC/GCE. The sensor based on P-Ru/NC can detect H2O2 in a wide range from 0.02 mM to 6.1 mM with a high sensitivity of 544.57 µA·mM−1·cm−2 and a low detection limit (4.41 µM). Therefore, this work demonstrated an effective sensing platform for non-enzymatic detection of H2O2.

Facile antisolvent crystallization-based synthesis of Cu/CoO nanocomposites as catalysts for the electrochemical detection of H2O2

Facile antisolvent crystallization-based synthesis of Cu/CoO nanocomposites as catalysts for the electrochemical detection of H2O2

Cobalt-based layered double hydroxide nanosheet-supported AuNPs for high performance electrochemical H2O2 detection

Enzyme-free electrochemical sensors with both high sensitivity and selectivity for H2O2 is highly desirable for biological science. During the electrochemical reduction of H2O2, the breakage of the O-O bond and subsequent stabilization of OH on the electrode are key to the performance of the electrochemical sensors. Noble metal nanoparticles could efficiently stabilize the above intermediate, but the stability of the naked nanoparticles was not satisfactory. Carbon-based supported materials are thus proposed, but lack efficient active sites for H2O2 reduction. Herein, cobalt-based layered double hydroxide-supported gold nanoparticles (AuNPs/Co-LDH) nanocomposite were fabricated as the electrode material for high-performance electrochemical H2O2 reduction in neutral media. Due to the abundant redox sites (Co2+/Co3+) and large surface area, AuNPs were formed in situ on Co-LDH with good dispersion and stability. Meanwhile, the redox sites of Co-LDH could also aid the electrochemical H2O2 reduction. A sensitivity of 406.61 μA mM−1 cm−2 and a detection limit of 0.19 μM were achieved, which outperformed most of reported nanomaterials. The above excellent electrochemical properties endow the follower-like AuNPs/Co-LDH as promising alternative to enzymes in the biological field.

Trimetallic metal–organic framework nanosheets as nanozymes for the electrochemical sensing of H2O2

A variety of two-dimensional (2D) metal–organic framework (MOF) nanosheets have been discovered with excellent peroxidase-like activity due to their merits of accessible active sites and large surface area. However, few methods can be used for the large-amount production of 2D MOF nanosheets. Herein, we report a simple room temperature solution phase method for the high-yield synthesis of 2D trimetallic MOF nanosheets with three kinds of metal ions as ligands. The as-synthesized NiCoM (M = Cu, Fe, and Zn) nanosheets showed markedly enhanced electrochemical activity due to the synergistic effect. Among these obtained nanosheets, NiCoFe showed the highest electrocatalytic activity, demonstrating that Fe played a dominant role in determining the activities of nanozymes. As a proof-of-concept application, 2D NiCoFe nanosheets are used as modified materials for the electrochemical detection of H2O2. The results showed that the fabricated sensor can detect hydrogen peroxide (H2O2 ) with a detection range of 5.0 μM − 15 mM, a detection limit of 2.1 μM, excellent selectivity and stability. Moreover, the fabricated NiCoFe nanosheet-based electrochemical sensor can be used for the detection of H2O2 in serum samples. Our work provides a scalable method for the large-scale synthesis of 2D trimetallic MOF nanosheets as enhanced nanozymes for various applications.

Synthesis of CuxO/Ag nanoparticles on exfoliated graphene: application for enhanced electrochemical detection of H2O2 in milk

In this paper, a novel composite is constructed as a non-enzymatic hydrogen peroxide (H2O2) sensor by liquid-phase exfoliation method, which is composed of copper oxide, cuprous oxide and silver nanoparticles doped few-layer-graphene (CuxO/Ag@FLG). Its surface morphology and composition were characterized by scanning electron microscopy (SEM) and X-ray photo spectroscopy (XPS), and its H2O2 sensing performances include catalytic reduction and quantitative detection were studied with electrochemical methods. Our sensor had a high sensitivity of 174.5 μA mM−1 cm−2 (R2 = 0.9978) in an extremely wide range of concentrations from 10 μM to 100 mM, a fast response (about 5 s) and a low limit of detection (S/N = 3) of 2.13 μM. The sensor exhibits outstanding selectivity in the presence of various biological interference, such as dopamine, ascorbic acid, uric acid, citric acid, etc. In addition, the constructed sensor continued 95% current responsiveness after 1 month of storage further points to its long-term stability. Last but not least, it has a good recovery rate (90.12–102.00%) in milk sold on the open market, indicating that it has broad application possibilities in the food industry and biological medicine.

RGO-Modified paper supported Globe Thistles-Like NiCo2S4 flexible electrodes enhancing H2O2 sensing

The Globe Thistles-Like (GTL) NiCo2S4 nanostructures were supported on reduced graphene oxide modified filter paper (FP). The prepared GTL NiCo2S4/rGO/FP is investigated as a disposable and flexible electrode for the electrochemical detection of H2O2 in alkaline media. Owing to the rich redox active sites, the synergistic effect between Co3+ and Ni2+, and the rapid electron transportation of substituting sulfur (S) for oxygen (O) in NiCo2O4, the GTL NiCo2S4/rGO/FP exhibits considerable enzyme-free H2O2 sensing performance with wide linear H2O2 ranging from 38.8 to 37306.8 μM, high sensitivity of 2.4326 mA mM−1 cm−2, and low detection limit of 0.08 μM. The GTL NiCo2S4/rGO/FP electrode has stable sensing performance and is highly selective toward analyte for physiological interfering species. The excellent electrochemical performance of GTL NiCo2S4/rGO/FP composite is attributed to the GTL structure of NiCo2S4. By studying the hydrothermal reaction time, electrochemical active surface area, and hydrophilic-hydrophobic surfaces of GTL NiCo2S4/rGO/FP composite, the relationship between the microstructure and sensing performance of the composite was elucidated. Surely this study opens up new possibilities for the application of low-cost, biodegradable flexible electrode materials in wearable sensors in the near future.

Correction: Green synthesis and characterization of Ag nanoparticles in a phytic acid/ascorbic acid/sodium hydroxide system and their application in the electrochemical detection of H2O2

Correction for ‘Green synthesis and characterization of Ag nanoparticles in a phytic acid/ascorbic acid/sodium hydroxide system and their application in the electrochemical detection of H2O2’ by Baolong Niu et al., New J. Chem., 2023, 47, 8797–8808, https://doi.org/10.1039/D2NJ06332H.