Peroxide Sensor Research Articles

Layered bimetallic hydroxide nanocage assembled on MnO2 nanotubes: A hierarchical porous sugar gourd-like electrocatalyst for the sensitive detection of hydrogen peroxide in food.

Hydrogen peroxide is used widely as a disinfection or bleaching additive during processing in the food industry. However, excessive residues of hydrogen peroxide in food have serious human health implications. In the present study, a novel electrochemical sensing electrode (MnO2/ZIF-67@LDH) with hierarchical porous sugar gourd-like structure was fabricated through a multi-step hydrothermal method using ZIF as the precursor. The unique porous nanocage structure of the sensing electrode provided multidimensional charge transfer channels and accelerated the electron transfer rate. As a hydrogen peroxide sensor, the electrode had two detection linear ranges of 1×10-3-4mmol L-1 and 4-8mmol L-1, and the detection limit was 0.26µmol L-1. The MnO2/ZIF-67@LDH sensor was also applied to determine the content of hydrogen peroxide in actual food samples of juice and milk, and satisfactory recovery were achieved. The present study provides a novel and effective design strategy for the construction of electrochemical sensing electrodes.

Chemically Bonded Carbon Nanotube Film to a Nanostructured Gold Electrode for Electrochemical Sensing of Hydrogen Peroxide

Chemically Bonded Carbon Nanotube Film to a Nanostructured Gold Electrode for Electrochemical Sensing of Hydrogen Peroxide

Structural Phase Transition of Mo2C for Enhancing Electrochemical Sensing of Hydrogen Peroxide

Regulating the electrocatalytic activity of metal carbides is the key to achieving highly sensitive electrochemical sensing. Molybdenum carbide (Mo2C) nanoparticles were anchored on the surface of nitrogen doped carbon nanomaterials (NC) through polymerization and calcination. By adjusting the calcination conditions, the crystal phase structure of Mo2C nanoparticles was successfully regulated, and two kinds of Mo2C nanoparticles with different crystal phase structure were obtained. The effect of the crystal structure of Mo2C on the electrocatalytic reduction of H2O2 was investigated. The results show that Mo2C with the hexagonal structure (H-Mo2C) has higher electrocatalytic activity for H2O2 reduction reaction, and the sensor based on H-Mo2C/NC could detect H2O2 in a wide linear range from 0.02 mM to 7.1 mM with a high sensitivity of 282.9 μA·mM−1·cm−2 and a low detection limit of 0.45 μM (S/N = 3). Moreover, the sensor can also accurately determine the content of H2O2 in disinfectant and milk samples. This study demonstrated Mo2C with the hexagonal structure as an effective sensing material for H2O2.

Interfacing Silver Nanoparticles with Hematene Nanosheets for the Electrochemical Sensing of Hydrogen Peroxide

Background: Hydrogen peroxide (H2O2) is an important metabolite that plays a crucial role in enzymatic reactions in living organisms. However, it acts as a reactive oxygen species (ROS) that causes various chronic diseases. The main challenging aspects in detecting H2O2 in body cells are the ultra-lowlevel concentrations and its reactivity. Hence, it is highly essential to develop a platform for H2O2 with high sensitivity and selectivity. Objective: In this work, we report an electrochemical biosensor for hydrogen peroxide (H2O2) by interfacing 3-dimensional silver nanoparticles (Ag-NPs) with 2-dimensional hematene (HMT) nanosheets. Methods: The two-dimensional nanomaterial, HMT, was exfoliated from natural iron ore hematite (α- Fe2O3) and characterized by Raman spectroscopy. The morphology of the Ag nanoparticles and HMT was imaged by scanning electron microscope. Electrochemical characterization of Ag/HMT modified glassy carbon electrode (GCE) was performed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Results: The fabricated sensor showed a wide linearity range of H2O2 concentrations from 0.99 μM to 1110 μM and a low detection limit of 0.16 μM using CV. Further, the sensor was successfully applied for the electrochemical sensing of hydrogen peroxide using chronoamperometry (CA) from 20 μM to 1110 μM (LOD 5.5 μM). Conclusion: The proposed electrochemical sensor for H2O2 is fast responding with a high sensitivity, and shows selectivity in the presence of biologically important molecules. These consequences suggested that the formation of heterostructures between 2D and 3D nanomaterials unveils the possibility of stable and selective electrochemical sensors for bioanalytics.

Construction of self-support three-dimensional nickel iron layered double hydroxide by dielectric barrier discharge microplasma for electrochemical sensing in food, serum and cell

With the development of non-enzyme sensors, non-noble metal catalysts have been widely utilized to construct glucose (Glu) or hydrogen peroxide (H2O2) sensors. However, most of them cannot achieve dual-function detection and are insensitive. In this paper, we prepared a NiFe layered double hydroxide (LDH) with a three-dimensional structure using dielectric barrier discharge microplasma (DBD microplasma) via a simple chemical reaction. The results demonstrate that this sensor exhibits sensitivities of 31591.0 μA·mM−1·cm−2 and 5199.3 μA·mM−1·cm−2 for Glu and H2O2 detection respectively. Additionally, wide linear ranges of 0.0004–2 mM and 0.0006–4 mM were achieved for Glu and H2O2 detection, respectively. Furthermore, we verified the applicability of this catalyst in analyzing human serum samples, cell samples, and food samples which yielded satisfactory results. The constructed sensor possesses advantages such as simplicity, efficient preparation, and high sensitivity.

Green reduction and uniform assembly of silver nanoparticles on polydopamine functionalized sulfur-doped graphitic carbon nitride nanosheets for highly sensitive H2O2 detection via nonenzymatic approach

In this study, we demonstrate a new strategy to fabricate an enzyme-free hydrogen peroxide (H2O2) sensor electrode based on silver nanoparticles (AgNPs) decorated polydopamine/sulfur-doped graphitic carbon nanocomposite (denoted as AgNPs@PDA/S-g-C3N4). The S-g-C3N4 nanosheets are derived from the pyrolysis of trithiocyanouric acid, followed by thermal exfoliation. A mussel-inspired PDA nanolayer enhances the solubility and high dispersion of S-g-C3N4 nanosheets and AgNPs in aqueous phase synthesis. The amine and catecholic functional groups of PDA are the major nucleation sites for Ag+ ions adsorption and ascorbic acid was further used as a green reducing agent for the growth of AgNPs. PDA adhesion layer can effectively connect the AgNPs and S-g-C3N4 nanosheets via electrostatic interaction to increase the stability and biocompatibility of the ternary composite structure. Various spectroscopy and microscopy techniques confirmed the formation of AgNPs@PDA/S-g-C3N4 nanocomposite. Our AgNPs@PDA/S-g-C3N4 nanocomposite fabricated disposable sensor exhibited outstanding sensing ability to H2O2 reduction at −0.65 V (vs. Ag/AgCl), which is confirmed through an amperometric detection method. The sensor exhibits rapid response (2 s) to H2O2 sensing with high sensitivity (1020 μA mM−1 cm−2), wide detection range (0.002–23 mM) and low limit of detection of 0.086 μM. The practicality of the H2O2 sensor was evaluated with commercial milk and mouthwash samples, which retained satisfactory recoveries. Thus, our results indicate that the PDA functionalization not only enhances the S-g-C3N4 solubility but also increases the interfacial charge transport in AgNPs@PDA/S-g-C3N4 nanocomposite material which develops a potential sensing method for nonenzymatic H2O2 sensor. Due to the effective surface modification strategies, such as PDA nanocoating and AgNPs deposition, the exfoliated S-g-C3N4 nanosheets gained excellent electrochemical properties, facilitating potential candidates in electrochemical applications.

Fabrication of Polyvinyl Alcohol Doped CuO Thin Films for Improved Amperometric-Non Enzymatic Hydrogen Peroxide Sensing

Fabrication of Polyvinyl Alcohol Doped CuO Thin Films for Improved Amperometric-Non Enzymatic Hydrogen Peroxide Sensing

Synergistic redox of dual-shaped silver nanostructures for highly selective sensing of hydrogen peroxide

A novel growth-based plasmonic sensor for hydrogen peroxide (H2O2) determination was developed from dual-shaped silver nanostructures consisting of starch-stabilized yellow silver nanospheres (AgNSs) and citrate-capped red silver nanoprisms (AgNPrs). AgNPrs were enlarged through a unique mechanism of AgNSs dissolution to silver ions which are subsequently reduced to silver metal by H2O2. Citrate-capping maintains the lateral anisotropic growth by protecting the AgNPrs from oxidation while exposing the sensitive edges to Ostwald ripening. This highly unique process addresses the selectivity issues encountered with decomposition-based AgNSs/NPrs sensors. Absorbance values from the AgNSs decomposition and AgNPrs growth facilitated a more sensitive spectrophotometric assay through ratiometric analysis. Increasing the concentration of the AgNSs/NPrs sensor to 80:40 ppm also improved sensitivity of naked eye detection of H2O2 by generating a wide range of color transitions. Furthermore, selectivity, accuracy and precision evaluation suggest that the dual-shaped silver nanostructure sensor is a potential alternative to H2O2 determination by allowing a simple, rapid, highly selective, and sensitive measurement.

Colorimetric sensor based on biogenic nanomaterials for high sensitive detection of hydrogen peroxide and multi-metals

Hydrogen peroxide (H2O2) and heavy metals, which are among the wastes of the industrial sector, become a threat to living things and the environment above certain concentrations. Therefore, the detection of both H2O2 and heavy metals with simple, low-cost, and fast analytical methods has gained great importance. The use of nanoparticles in colorimetric sensor technology for the detection of these analytes provides great advantages. In recent years, green synthesis of nanomaterials with products that can be considered biowaste is among the popular topics. In this study, silver/silver chloride nanoparticles (Ag@AgCl NPs) were synthesized using the green synthesis method as an eco-friendly and cheap method, the green algae extract was used as a reducing agent. The characterization of Ag@AgCl nanoparticles and green algae extract was carried out with several techniques such as Transmission Electron Microscopy (TEM), UV–Visible spectrometry (UV–Vis), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction patterns (XRD) methods were used for characterization. According to TEM analysis, the Ag@AgCl NPs typically spherical in form and range in size from 4 to 10 nm, and UV–vis showed the formation of surface plasmon resonance (SPR) of the Ag@AgCl between 400 and 450 nm. In addition, its activity as a colorimetric sensor for hydrogen peroxide (H2O2) and multi-metal detection was evaluated. Interestingly, Ag/AgCl NPs caused different color formations for 3 metals simultaneously in the sensor study for heavy metal detection, and Fe3+, Cu2+, and Cr6+ ions were detected. The R2 values for H2O2, Fe3+, Cu2+, and Cr6+ were 0.9360, 0.9961, 0.9787, and 0.9625 the limit of detection (LOD) was 43.75, 1.69, 3.18, and 5.05 ppb (ng/mL), respectively. It was determined that Ag@AgCl NPs have the potential to be used as a colorimetric sensor for the detection of H2O2 and heavy metals from wastewater.

Catalytically Synthesized Prussian Blue by a One-Step Copolymerization of Polydopamine-Polypyrrole for Electrochemical Sensing of Hydrogen Peroxide

Catalytically Synthesized Prussian Blue by a One-Step Copolymerization of Polydopamine-Polypyrrole for Electrochemical Sensing of Hydrogen Peroxide

Study of Chitosan-Stabilized Ti3C2Tx MXene for Ultrasensitive and Interference-Free Detection of Gaseous H2O2.

The development of sensitive, selective, and reliable gaseous hydrogen peroxide (H2O2) sensors operating at room temperature still represents a remaining challenge. In this work, we have investigated and combined the advantageous properties of a two-dimensional Ti3C2Tx MXene material that exhibits a large specific surface area and high surface activity, with favorable conducting and stabilizing properties of chitosan. The MXene-chitosan membrane was deposited on the ferrocyanide-modified screen-printed working carbon electrode, followed by applying poly(acrylic acid) as an electrolyte and accumulation medium for gaseous H2O2. The sensor showed highly sensitive and selective electroanalytical performance for detecting trace concentrations of gaseous H2O2 with a very low detection limit of 4 μg m-3 (4 ppbv), linear response in the studied concentration range of 0.5-30.0 mg m-3, and good reproducibility with an RSD of 1.3%. The applicability of the sensor was demonstrated by point-of-interest detection of gaseous H2O2 during the real hair bleaching process with a 9 and 12% H2O2 solution.

Ultrasensitive Nonenzymatic Real-Time Hydrogen Peroxide Monitoring Using Gold Nanoparticle-Decorated Titanium Dioxide Nanotube Electrodes.

An amperometric enzyme-free hydrogen peroxide (H2O2) sensor was developed by catalytically stabilizing active gold nanoparticles (Au NPs) of 4-5 nm on a porous titanium dioxide nanotube (TiO2 NTs) electrode. The Au NPs were homogeneously distributed on anatase TiO2 NTs with an outer diameter of ~102 nm, an inner diameter of ~60 nm, and a wall of thickness of ~40 nm. The cyclic voltammogram of the composite electrode showed a pair of redox peaks characterizing the electrocatalytic reduction of H2O2. The entrapping of Au NPs on TiO2 NTs prevented aggregation and facilitated good electrical conductivity and electron transfer rate, thus generating a wide linear range, a low detection limit of ~104 nM, and high sensitivity of ~519 µA/mM, as well as excellent selectivity, reproducibility, repeatability, and stability over 60 days. Furthermore, excellent recovery and relative standard deviation (RSD) were achieved in real samples, which were tap water, milk, and Lactobacillus plantarum bacteria, thereby verifying the accuracy and potentiality of the developed nonenzymatic sensor.

Reversible CeO2–x and CeO2–x:Eu3+ Luminescent Hydrogen Peroxide Sensors with Recovery Rates Controlled by Temperature and UV Irradiation

Hydrogen peroxide (HP) plays an indispensable role in living organisms, being both an intracellular messenger and a substrate or byproduct of a number of enzymes. In this way, HP sensing is important for monitoring the activity of various cell systems and assessing the redox balance of the cell as whole. HP sensors based on luminescent inorganic nanoparticles can be considered as a prospective alternative to traditional dye- and enzyme-based sensors, which usually are unstable and nonreversible. The undoped (CeO2–x) and Eu3+-doped (CeO2–x:Eu3+) colloidal ceria nanoparticles studied in the paper provide HP detection by reversible quenching of Eu3+ (590 nm) and Ce3+ (430 nm) luminescence bands. The dynamics of Eu3+ and Ce3+ luminescence quenching and recovery during HP-nanoceria interaction provides an insight into the microscopic mechanisms of HP sensing by CeO2–x and CeO2–x:Eu3+ nanoparticles. Both CeO2–x and CeO2–x:Eu3+ luminescent sensors are reversible and their recovery rates can be sufficiently increased by temperature and continuous UV irradiation. At the same time, Eu3+ ions deteriorate the catalase-mimetic activity of CeO2–x NPs and worsen their antioxidant properties, which should be kept in mind while using these sensors in biological media.

Hydrogen peroxide sensor HyPer7 illuminates tissue-specific plastid redox dynamics.

The visualization of photosynthesis-derived reactive oxygen species has been experimentally limited to pH-sensitive probes, unspecific redox dyes, and whole-plant phenotyping. Recent emergence of probes that circumvent these limitations permits advanced experimental approaches to investigate in situ plastid redox properties. Despite growing evidence of heterogeneity in photosynthetic plastids, investigations have not addressed the potential for spatial variation in redox and/or reactive oxygen dynamics. To study the dynamics of H2O2 in distinct plastid types, we targeted the pH-insensitive, highly specific probe HyPer7 to the plastid stroma in Arabidopsis (Arabidopsis thaliana). Using HyPer7 and glutathione redox potential (EGSH) probe for redox-active green fluorescent protein 2 genetically fused to the redox enzyme human glutaredoxin-1 with live cell imaging and optical dissection of cell types, we report heterogeneities in H2O2 accumulation and redox buffering within distinct epidermal plastids in response to excess light and hormone application. Our observations suggest that plastid types can be differentiated by their physiological redox features. These data underscore the variation in photosynthetic plastid redox dynamics and demonstrate the need for cell-type-specific observations in future plastid phenotyping.

Author Correction: NiTe Magnetic Semiconductor Nanorods for Optical Limiting and Hydrogen Peroxide Sensor

Author Correction: NiTe Magnetic Semiconductor Nanorods for Optical Limiting and Hydrogen Peroxide Sensor

Development, Characterization, and Structural Analysis of a Genetically Encoded Red Fluorescent Peroxynitrite Biosensor.

Boronic acid-containing fluorescent molecules have been widely used to sense hydrogen peroxide and peroxynitrite, which are important reactive oxygen and nitrogen species in biological systems. However, it has been challenging to gain specificity. Our previous studies developed genetically encoded, green fluorescent peroxynitrite biosensors by genetically incorporating a boronic acid-containing noncanonical amino acid (ncAA), p-boronophenylalanine (pBoF), into the chromophore of circularly permuted green fluorescent proteins (cpGFPs). In this work, we introduced pBoF to amino acid residues spatially close to the chromophore of an enhanced circularly permuted red fluorescent protein (ecpApple). Our effort has resulted in two responsive ecpApple mutants: one bestows reactivity toward both peroxynitrite and hydrogen peroxide, while the other, namely, pnRFP, is a selective red fluorescent peroxynitrite biosensor. We characterized pnRFP in vitro and in live mammalian cells. We further studied the structure and sensing mechanism of pnRFP using X-ray crystallography, 11B-NMR, and computational methods. The boron atom in pnRFP adopts an sp2-hybridization geometry in a hydrophobic pocket, and the reaction of pnRFP with peroxynitrite generates a product with a twisted chromophore, corroborating the observed "turn-off" fluorescence response. Thus, this study extends the color palette of genetically encoded peroxynitrite biosensors, provides insight into the response mechanism of the new biosensor, and demonstrates the versatility of using protein scaffolds to modulate chemoreactivity.

Rethreading Design of Ratiometric roGFP2 Mimetic Peptide for Hydrogen Peroxide Sensing.

Reconstruction of the miniaturized peptide to mimic the tailored functions of protein has been attractive but challenging. Herein, initialized from the crystal structure of redox-sensitive green fluorescent protein-2 (roGFP2), we propose a practical approach to construct the roGFP2 mimetic peptide by rethreading the aromatic residues adjacent to the chromophore fragment. By fine-tuning the residues of peptides, a mini tetrapeptide (Cys-Phe-Phe-His) was designed, which can act as a hydrogen peroxide sensor using its ratiometric fluorescence. The roGFP2 mimetic tetrapeptide is biocompatible and photostable and has competitive fluorescent properties with roGFP2 by the virtue of its assembly induced emissions. We expand the ratiometric tetrapeptide for sensing hydrogen peroxide in acidic chambers. The results provide a promising approach for the artificial design of miniaturized peptides with the desired function.

Redox-stress response resistance (RRR) mediated by hyperoxidation of peroxiredoxin 2 in senescent cells.

Aging is closely related to redox regulation. In our previous work, we proposed a new concept, "redox-stress response capacity (RRC)," and found that the decline in RRC was a dynamic characteristic of aging. However, the mechanism of RRC decline during aging remains unknown. In this study, using the senescent human fibroblast cell model and Caenorhabditis elegans model, we identified that peroxiredoxin 2 (PRDX2), as a hydrogen peroxide (H2O2) sensor, was involved in mediating RRC. PRDX2 knockdown led to a decline of RRC and accelerated senescence in fibroblasts and prdx-2 mutant C. elegans also showed decreased RRC. The mechanism study showed that the decreased sensor activity of PRDX2 was related to the increase in hyperoxidation of PRDX2 in senescent cells. Moreover, the level of PRDX2 hyperoxidation also increased in old C. elegans. Simultaneous overexpression of both PRDX2 and sulfiredoxin (SRX) rescued the reduced RRC and delayed senescence. The increase in PRDX2 hyperoxidation in senescent cells led to a decrease in its sensor activity, resulting in the decreased cellular response to H2O2, which is similar to the mechanism of insulin resistance due to the lower insulin receptor sensitivity. Treatment of young cells with a high level of H2O2 to induce a higher level of PRDX2-SO3 resulted in mimicking the RRC decline in senescent cells, which is also similar to a model of insulin resistance induced by high levels of insulin. All these results thrillingly indicate that there is an insulin-resistance-like phenomenon in senescent cells, we named it redox-stress response resistance, RRR. RRR in senescent cells is an important new discovery that explains RRC decline during aging and reveals the internal relationship between redox regulation and aging from a new perspective.

ZnO@C Microballs Wrapped with Ni(OH)2 Nanofilms for Electrochemical Sensing of Glucose and Hydrogen Peroxide.

Tailor-made metal oxide/hydroxide core-shell structures are promising for the fabrication of effective electrocatalysts. Here, we report the development of a core-shell structure based on carbon-doped and Ni(OH)2 nanofilms wrapped ZnO microballs (NFs-Ni(OH)2 /ZnO@C MBs) for glucose and hydrogen peroxide (H2 O2 ) monitoring. The unique ball-like morphology of the designed structure is achieved through a facile solvothermal strategy by the control of reaction conditions. Typically, ZnO@C MBs offer highly conductive core, and the shell of Ni(OH)2 nanofilms increases the density of catalytic active sites. The interesting morphology and the brilliant electrocatalytic efficacy of designed hybrid, encourage us to design a multi-mode sensor for glucose and H2 O2 screening. The NFs-Ni(OH)2 /ZnO@C MBs/GCE glucose sensor presented good sensitivities (647.899 & 161.550 μA (mmol L-1 )-1 cm-2 ), a quick response (<4 s), lower limit of detection (0.04 μmol L-1 ), and wide detection range (0.004-1.13 & 1.13-5.02 mmol L-1 ). Similarly, the same electrode revealed excellent H2 O2 sensing features including good sensitivities, two linear parts of 3.5-452 and 452-1374 μmol L-1 , and detection limit of 0.03 μmol L-1 as well as high selectivity. Thus, the development of novel hybrid core-shell structure is useful for potential applications in glucose and H2 O2 screening from environmental and physiological samples.

Improving self-supported nanowire arrays using response surface methodology for the synthesis of a H2O2 nanostructured sensor

In this paper, we introduce a data-driven approach for optimizing the design of highly sensitive hydrogen peroxide (H2O2) sensors based on self-supported nickel nanowire (Ni NW) arrays using response surface methodology (RSM). Our goal is to enhance the performance of the sensor by customizing the length of Ni NW while optimizing the working conditions, including the H2O2 concentration and applied potential. Focusing solely on the commercially available porous membranes, we successfully employ RSM to identify the optimal conditions for the sensor: a NW length of 2.64 μm, an optimal concentration of 3.25 mM H2O2, and a detection potential of 0.02 V. We fabricate a sensor with the optimal NW length and validate its performance through comparison to sensors with different NW lengths, such as a planar Ni sensor and a previously investigated nanostructured sensor. Our optimized sensor achieves a 50% reduction in the limit of detection (LOD) and an 18% increase in sensitivity compared with the previously investigated nanostructured sensor. Moreover, the optimized sensor is at least 35 times more sensitive for H2O2 detection than sensors with planar geometries, which are standard in commercial applications. Our results highlight the potential of RSM as a powerful, cost-effective, and theoretically agnostic tool for optimizing nanostructured sensors and accelerating the design-build-test cycle. The optimized H2O2 sensor can be applied in various fields, including the food industry, medical diagnostics, and environmental monitoring. This sensor can significantly enhance glucose detection in non-invasive samples such as tears and saliva when combined with immobilized glucose oxidase enzymes, which is crucial for continuous glucose monitoring in diabetes mellitus patients. The methodology presented in this study allows further extensions to investigate other design variables and sensing materials as well as optimize sensors for detecting different substances, fostering advancements in sensor technologies.