H2O2 Sensing Research Articles

Laser-Induced Copper/Carbon Nanocomposite from Anodically Electrodeposited Chitosan for H2O2 Sensing

This work presents anodically electrodeposited copper (Cu)/chitosan gel as a novel precursor for synthesizing a Cu/carbon nanocomposite through laser-induced carbonization. Metal/carbon nanocomposites offering advantageous properties compared to their individual counterparts stand out in various applications, particularly in those involving electrochemical phenomena. However, their synthesis often suffers from complicated and time-consuming synthesis procedures. Here, we integrate anodic electrodeposition and laser-induced carbonization to yield a rapid, simple, and inexpensive procedure for synthesizing metal/carbon nanocomposite. A precursor composite involving Cu-coordinated chitosan film is achieved through anodic electrodeposition on a copper anode. Irradiation by an infrared laser with optimized parameters results in the thermochemical decomposition of the Cu/chitosan composite, rapidly forming a nanocomposite material featuring highly graphitized and porous carbon materials. Elemental mapping confirms the formation of the nanocomposite, although no crystalline phases of copper are observed during X-ray diffraction. This can be attributed to the rapid nature of the laser-carbonization process. The nanocomposite material is further demonstrated for electrochemical sensing of hydrogen peroxide (H2O2), exhibiting a sensitivity of 2.65 mM−1 for concentrations ranging from 0.01 mM to 0.1 mM H2O2, and 0.01 ± 0.01 mM−1 for concentrations from 0.1 to 10 mM H2O2. These sensitivities are comparable to other non-enzymatic H2O2 biosensors. The finding of this work signifies a rapid and facile method for synthesizing metal/carbon nanocomposites with strong implications for the field of biosensors.

Electrophoretic Deposition of Co3O4 Particles/Reduced Graphene Oxide Composites for Efficient Non-Enzymatic H2O2 Sensing.

In this work, the facile fabrication of Co3O4 particles/reduced graphene oxide (Co3O4/rGO) composites on Indium tin oxide (ITO) slide was achieved by an electrophoretic deposition and annealing process. The deposition time and ratio of the precursors were optimized. Structural characterization and chemical composition investigation indicated successful loading of Co3O4 particles on graphene sheets. When applied as a non-enzymatic H2O2 sensor, Co3O4/rGO showed significant electrocatalytic activity, with a wide linear range (0.1-19.5 mM) and high sensitivity (0.2247 mA mM-1 cm-2). The good anti-interference ability, reproducibility, and long-term stability of the constructed sensor were also presented. The application of Co3O4/rGO in real sample analysis was evaluated in human urine sample with satisfactory results, indicating the feasibility of the sensor in physiological and medical applications.

Synthesis of Bimetallic Ni-Co Phosphide Nanosheets for Electrochemical Non-Enzymatic H2O2 Sensing

NiCoP nanosheets (NSs) were successfully synthesized using the hydrothermal and high-temperature phosphorization process. The obtained NiCoP NSs were immobilized on a glassy carbon electrode (GCE) and used to construct a novel sensing platform for electrochemical non-enzymatic H2O2 sensing. Physicochemical characteristics of NiCoP NSs were obtained by field-emission scanning electron microscopy (FESEM), field-emission transmission electron microscope (FETEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). In addition, the electrochemical properties of NiCoP NSs were obtained by cyclic voltammetry (CV) and chronoamperometry (CA) towards the non-enzymatic detection of H2O2. FESEM and FETEM images provided a morphological insight (the unique nanosheets morphology of NiCoP) that could expose more active sites to promote mass/charge transport at the electrode/electrolyte interface. XRD and XPS results also confirmed the crystalline nature of the NiCoP nanosheets and the coexistence of multiple transitional metal oxidation states in NiCoP nanosheets. These unique physicochemical characteristics had a degree of contribution to ensuring enhancement in the electrochemical behavior. As a result, the synthesized NiCoP NSs composed of intercalated nanosheets, as well as the synergistic interaction between bimetallic Ni/Co and P atoms exhibited excellent electrocatalytical activity towards H2O2 electroreduction at neutral medium. As the results showed, the electrochemical sensing based on NiCoP NSs displayed a linear range of 0.05~4 mM, a sensitivity of 225.7 μA mM-1 cm-2, a limit of detection (LOD) of 1.190 μM, and good selectivity. It was concluded that NiCoP NSs-based electrochemical sensing might open new opportunities for future construction of H2O2 sensing platforms.

Hollow Spherical NiCo2O4 and Gold Nanoparticle Composite for Electrochemical Non-Enzymatic Glucose and H2O2 Sensing

A novel electrochemical non-enzymatic sensor for glucose and H2O2 based on metal organic framework (MOF)-derived cobalt-nickel bimetallic oxides (NiCo2O4) and gold nanoparticle (AuNPs) composite modified glassy carbon electrode (GCE) was fabricated in this paper. The structure and morphology of the prepared materials was successfully characterised by X-ray diffraction (XRD), element mapping images and scanning electron microscopy (SEM). Moreover, the electrocatalytic activity for glucose and H2O2 was investigated at the NiCo2O4/AuNPs/GCE using cyclic voltammetry (CV) and amperometric i–t technique. The catalytic currents for glucose and H2O2 are proportional to their concentrations in the range of 0.2 μM–581 μM and 0.5 μM–1774.5 μM, respectively. The corresponding limits of detection (LOD) were calcuated be 0.0081 μM and 0.181 μM for glucose and H2O2. Furthermore, the NiCo2O4/AuNPs/GCE shows excellent stability, reproducibility and anti-interference ability.

Platinum/carbon dots nanocomposites from palm bunch hydrothermal synthesis as highly efficient peroxidase mimics for ultra-low H2O2 sensing platform through dual mode of colorimetric and fluorescent detection

Detection of hydrogen peroxide and glucose in nanomolar level is crucial for point-of-care medical diagnosis. It has been reported that human's central nervous system diseases such as Alzheimer's disease, Parkinson's disease, and even amyotrophic lateral sclerosis, are presumably caused H2O2 or reactive radical species (ROS). Sensing of H2O2 released from human biofluids, tissues, organ from metabolism disorder at ultra-low concentration assists for early identification of severe diabetis mellitus related to glucose, and heart attack, as well as stroke related to cholesterol. In this work, carbon dots (CDs) having an average diameter at 6.99 nm with highly photoluminescence performance were successfully synthesized from palm empty fruit bunch (EFB) using green and environmentally friendly process via hydrothermal condition. CDs acted well on peroxidase-like activity for H2O2 detection at room temperature, however their sensitivity on ultra-low H2O2 concentration needed to be improved. To enhance their reactivity on H2O2 nanozyme activity at room temperature, synthesis of hybrid metal nanoparticles (AgNPs and PtNPs) on CDs surface was established. The findings exhibited that CDs/PtNPs was the most suitable nanozyme achieving highly efficient peroxidase mimic for dual mode of colorimetric and fluorescent H2O2 sensing platform at very low limit of detection of 0.01 mM (10 nM) H2O2.

Progress of Advanced Nanomaterials in the Non-Enzymatic Electrochemical Sensing of Glucose and H2O2.

Non-enzymatic sensing has been in the research limelight, and most sensors based on nanomaterials are designed to detect single analytes. The simultaneous detection of analytes that together exist in biological organisms necessitates the development of effective and efficient non-enzymatic electrodes in sensing. In this regard, the development of sensing elements for detecting glucose and hydrogen peroxide (H2O2) is significant. Non-enzymatic sensing is more economical and has a longer lifetime than enzymatic electrochemical sensing, but it has several drawbacks, such as high working potential, slow electrode kinetics, poisoning from intermediate species and weak sensing parameters. We comprehensively review the recent developments in non-enzymatic glucose and H2O2 (NEGH) sensing by focusing mainly on the sensing performance, electro catalytic mechanism, morphology and design of electrode materials. Various types of nanomaterials with metal/metal oxides and hybrid metallic nanocomposites are discussed. A comparison of glucose and H2O2 sensing parameters using the same electrode materials is outlined to predict the efficient sensing performance of advanced nanomaterials. Recent innovative approaches to improve the NEGH sensitivity, selectivity and stability in real-time applications are critically discussed, which have not been sufficiently addressed in the previous reviews. Finally, the challenges, future trends, and prospects associated with advanced nanomaterials for NEGH sensing are considered. We believe this article will help to understand the selection of advanced materials for dual/multi non-enzymatic sensing issues and will also be beneficial for researchers to make breakthrough progress in the area of non-enzymatic sensing of dual/multi biomolecules.

Synthesis of Silver Nanoparticles by Ocimum basilicum Seed Extract and its Application in H2O2 Sensing

Synthesis of Silver Nanoparticles by Ocimum basilicum Seed Extract and its Application in H2O2 Sensing

Synthesis of Two Mononuclear Schiff Base Metal (M = Fe, Cu) Complexes: MOF Structure, Dye Degradation, H2O2 Sensing, and DNA Binding Property.

O-Vanillin and ethylenediamine were used for the synthesis of N,N′-bis(O-vanillinidene)ethylenediamine (O-VEDH2) Schiff base ligand, which was characterized by UV–visible and 1H NMR spectroscopy. The Schiff base ligand O-VEDH2 has been employed to synthesize novel [C18H22FeN2O6]NO3 (1) and C18H16CuN2O5 (2) complexes by the simple slow evaporation method. The single crystals were characterized by X-ray crystallography, as well as Fourier-transform infrared and UV–visible spectroscopy techniques. Complexes 1 and 2 crystallize in monoclinic and orthorhombic space groups with P121/n1 (14) and Pnma (62) point groups, respectively, and both show metal–organic frameworks like structures. Complexes 1 and 2 have optical band gaps of 4.1 and 2.9 eV, respectively, indicating their semiconducting properties. The dye degradation activity and H2O2 sensing of the complexes 1 and 2 were determined in different conditions. The photocatalytic test was performed in the presence of sunlight, methylene blue (MB), and complexes 1 and 2. An interesting result was obtained that complex 2 has degradation ability against MB and the rate constant (K) is 5.46 × 10–5 s–1, whereas complex 1 has H2O2 sensing properties. Both complexes are bound to Calf-thymus DNA by intercalation binding mode, and binding constants (Kb) of complexes 1 and 2 are 3.77 × 103 and 1.49 × 104 M–1, respectively.

Facile Synthesis of Fe-MOF/rGO nanocomposite as an Efficient Electrocatalyst for Nonenzymatic H2O2 Sensing

Facile Synthesis of Fe-MOF/rGO nanocomposite as an Efficient Electrocatalyst for Nonenzymatic H2O2 Sensing

Self-Assembled Monolayers of Vitamin B12 over N-Doped Graphene: A Promising Electro-Catalyst for Hydrogen Evolution and Electro-Oxidative Sensing of H2O2

The redox, chemical and biochemical characteristics of molecular hydrogen (H2) and hydrogen peroxide (H2O2) promise sustainable, economically and environmentally friendly means to address some serious global issues related to energy, environment and human health. However, the non-availability of a cheap, efficient and durable electrocatalyst continues to hamper the practical exploitation of H2 and H2O2 as solution to these challenges. In the work to be presented, we shall present a simple strategy for the self-assembling of Vitamin B12 (Vit.B12) over nitrogen-doped graphene (NGr) for fabrication of Vit.B12-NGr nanohybrids; an electrochemically stable, reusable electrocatalyst with an excellent prospect for hydrogen evolution reaction (HER) and non-enzymatic electro-oxidative sensing of H2O2. Through the data recorded for the characterization of the Vit.B12-NGr nanohybrids through various techniques it shall be clearly proven that the conceived method ensures the self-assembling of Vitamin B12 as a monolayer over N-Gr. Results from our detailed voltammetric investigations over the Vit.B12-NGr modified electrodes besides establishing the redox accessibility, stability and enhanced activity of Co(II) centres in Vit.B12-NGr composites also suggest that the presence of NGr in Vit.B12-NGr composite not only assists the directed ET to Vit.B12, but it also improves the stability of the resulting composite by minimizing its loss to the solution phase. Results from our electrocatalytic investigations clearly demonstrate the excellent stability and electrocatalytic activity of Vit.B12-NGr nanohybrid towards HER (Figure 1). For HER, the Vit.B12-NGr nanohybrid displays onset potential of -0.096 V vs RHE, a low Tafel slope of ca. 68.3 mV/dec and an overpotential requirement of just -0.210 V for 10 mAcm-2. Moreover, we shall present results from our electro-sensing investigation that establish that the Vit.B12-NGr is a promising electrocatalytic surface for the electro-oxidative sensing of H2O2. In our investigations we observed that use of Vit.B12-NGr ensures the H2O2 sensing with a sensitivity of 430 µA/mM (8.775 µAmM-1cm-2) and a limit of detection as low as 0.02 µM. These HER activity and H2O2 sensing parameters displayed by Vit.B12-NGr are either superior or comparable to those observed for the various recently reported state-of-the-art HER electrocatalysts and H2O2 sensors. Figure 1. HER performance at various electrodes (A) LSV polarization curves (negative direction) of bare-GCE (black line), NGr/GCE (red line), Vit.B12-NGr/GCE (blue line) and Pt/C (green dotted line)in 0.5 M H2SO4 with scan rate 100 mV/s. (B) The corresponding HER Tafel plot of NGr/GCE, Vit.B12-NGr/GCE and Pt/C. (C) LSV curves on Vit.B12-NGr/GCE surface at the first cycle (black) and after 50 cycles (red dotted) (scan rate 100 mV/s). Figure 1

Gold Nanoparticles and [PEDOT-Poly(D,L-Lactic Acid)] Composite: Synthesis, Characterization and Application to H2O2 Sensing

Biocompatible electrochemical devices are challenging to develop due to the toxicity of many advanced electrode materials and the difficulty to degrade the discarded material. Few recent advances were made in the synthesis of conducting biodegradable composites of polymers for electrode materials. In this article we describe the synthesis of two new inorganic/organic nanocomposites of Au nanoparticles and conducting polymers based on the biodegradable polymer poly(D,L-lactic acid) (PDLLA): Au nanoparticles/oligomers of 3,4-ethylenedioxythiophene (EDOT)-PDLLA and Au nanoparticles with poly(3,4-ethylenedioxythiophene) (PEDOT)-PDLLA. The nanocomposites were carefully analyzed; the gold nanoparticles mean sizes were 8 ± 3 and 7 ± 2 nm, respectively. 1H and 13C nuclear magnetic resonance (NMR) demonstrated the polymerization of EDOT-PDLLA made through one-pot reaction with AuIII precursor. Raman spectra show that PEDOT-PDLLA is formed in the synthesis of Au/PEDOT-PDLLA. The immobilization of Au/PEDOT-PDLLA on glassy carbon electrodes is easy and more stable than the immobilization of simple PEDOT. Au/PEDOT-PDLLA catalyzes the reduction of H2O2(aq), which was detected by chronoamperometry. The sensor is stable and presents sensitivity of 8.36 × 10-3 A mol-1 L cm-2, linear range of 1-45 mmol L-1 and limit of detection of 0.17 mmol L-1.

Graphene Supported Metal Oxide for Non-Enzymatic H2O2 Sensing

Research & Development in Material Science Graphene Supported Metal Oxide for Non-Enzymatic H2O2 Sensing J Sharath Kumar1,2, Naresh Chandra Murmu1,2 and Tapas Kuila1,2* 1Surface Engineering & Tribology Division, Council of Scientific and Industrial Research-Central Mechanical Engineering Research Institute, India 2Academy of Scientific and Innovative Research (AcSIR), CSIR-CMERI Campus, India *Corresponding author: Tapas Kuila, Surface Engineering & Tribology Division, Council of Scientific and Industrial Research-Central Mechanical Engineering Research Institute, Academy of Scientific and Innovative Research (AcSIR), CSIR-CMERI Campus, Durgapur -713209, India Submission: February 21, 2018; Published: March 08, 2018 DOI: 10.31031/RDMS.2018.04.000584 Volume 4 Issue 2 March 2018

Electrochemical Synthesis of a Binary Mn-Co Oxides Decorated Graphene Nanocomposites for Application in Nonenzymatic H2O2 Sensing

Electrochemical Synthesis of a Binary Mn-Co Oxides Decorated Graphene Nanocomposites for Application in Nonenzymatic H2O2 Sensing

Porous Aromatic Framework as an Efficient Metal-Free Electro-catalyst for Non-enzymatic H2 O2 Sensing.

A porous aromatic framework (referred as PAF-39) based on tetrakis(4-(9H-carbazol-9-yl)phenyl)methane has been designed and synthesized by oxidative coupling polymerization. PAF-39 exhibits high surface area and high heat of adsorption (Qst ) of CO2 . Especially, the PAF material was applied for non-enzymatic H2 O2 sensing.

Carbon-Nitrogen Doped Nickel Oxide Microspheres for Non-Enzymatic H2O2 Sensing

Carbon-Nitrogen Doped Nickel Oxide Microspheres for Non-Enzymatic H₂O₂ Sensing

Electrocatalytic Investigation of Group X Metal Nanoparticles Loaded TiO2 Nanotubes Powder Prepared by Rapid Breakdown Anodization for Selective H2O2 Sensing

Amperometric based hydrogen peroxide (H2O2) sensor developed using a composite of Titania (TiO2) nanotubes (NTs) powder individually loaded with Ni, Pd or Pt metal nanoparticles is reported. The bundles of TiO2 NTs powder prepared via rapid breakdown anodization have a length of 5 to 6 μm and outer diameter of 20 to 25 nm. Sodium borohydride based reduction of chloroplatinic acid and palladium chloride with the TiO2 NTs powder resulted in Pt/TiO2 and Pd/TiO2 composite materials. Ni/TiO2 composite was prepared by mixing directly Ni nanoparticles (35 nm) and TiO2 NTs. The electrochemical performance of the Pt/TiO2, Pd/TiO2 and Ni/TiO2 electrodes exhibited better selectivity, sensitivity and wide linear range for the detection of the analyte H2O2, in comparison with pristine TiO2 NTs powder. Among the composites, the Ni/TiO2 electrode exhibited high electrocatalytic activity toward oxidation of H2O2 in 0.1 M NaOH solution. At an applied potential of +0.45 V vs. NCE, the Ni/TiO2 composite electrode exhibits a linear dependence (R2 = 0.997) in the H2O2 concentration up to 3365 μM with a sensitivity of 5.3 μA mM−1 and detection limit of 20 μM. In general, the Pt, Pd and Ni/ TiO2 nanocomposite electrodes exhibit better sensitivity to the detection of H2O2.

9 - Dissecting the Mechanism of Prx2-Mediated H2O2 Sensing

Peroxiredoxins (Prx) are a large family of thiol-dependent peroxidases that reduce hydroperoxides at expense of thioredoxin or other disulfide reductases. Human Prx2 is well expressed in the cytosol, a 2-Cys typical Prx. The first reaction in the catalytic cycle, the peroxidatic cysteine with H 2 O 2 , is extraordinary fast (10 8 M -1 s -1 ) placing Prx as preferential target for intracellular H 2 O 2 . Oxidation to sulfenic acid of the reactive Cys inside the decameric reduced protein results in conformational changes at the active site needed for the attack of the resolving Cys to form a disulfide. This conformational transition needed for catalysis imposes a kinetic pause that can result in overoxidation of the active-site Cys before disulfide formation, a modification that has been linked to redox signaling pathways. Among mammalian Prx, Prx2 is particularly sensitive to hyperoxidation and sensitivity to hyperoxidation is linked to the rate of disulfide formation. By stopped-flow fluorimetry we characterize the different kinetic steps in the catalysis at increasing levels of H 2 O 2 and at different pHs. Our results confirm the first step in the cycle, reaction with H 2 O 2 is fast, and step 2, resolution, is the rate limiting step. The peroxidatic cys is acidic, pKa = 4.8 but it is not the only factor responsible for the outstanding rate of H 2 O 2 reduction. The reactivity of the groups involved in second step (resolving thiol and peroxidatic sulfenic) are not affected by changes in the pKas (8.0 and 7.0, respectively) but rather determined by conformational changes, from the so-called fully-folded FF to the locally-unfolded LU conformation.

Optical Devices Constructed from Ferrocene-Modified Microgels for H2O2 Sensing.

Ferrocene-modified poly(N-isopropylacrylamide)-based microgels were synthesized, characterized, and used to construct optical devices (etalons). The response of the microgels and etalons to H2O2 was investigated, and we show that both the microgel diameter and the optical properties of the etalons depend on the solution concentration of H2O2 from 0.6 to 35 mM. This behavior is a direct result of the oxidation of ferrocene, which influences the microgel diameter. This was also demonstrated by electrochemical-mediated oxidation/reduction of ferrocene using cyclic voltammetry. We go on to show that these materials could be used to monitor H2O2 that is generated from enzymatic reactions. Specifically, we show that the H2O2 generated from the oxidation of glucose catalyzed by glucose oxidase could be quantified. Finally, the devices can be reused multiple times via a regeneration process. This investigation illustrates the versatility of the etalon system to detect species of broad relevance and how they could potentially be used to quantify products of biological reactions.

MWCNT Based Non-Enzymatic H2O2 Sensor: Influence of Amine Functionalization on the Electrochemical H2O2 Sensing

This article reports on the influence of amine functionalization on enzyme free hydrogen peroxide (H2O2) sensing properties of Multiwall Carbon nanotubes (MWCNTs). Three amine groups with different molecular structure such as ethylene diamine (EDA), dimethylamine (DMA), triethyl amine (TEA), were functionalized on MWCNTs. Functionalization was confirmed by Raman, FT-IR and zeta potential measurements. The effect of scan rate, applied potential, pH and H2O2 concentration was investigated to evaluate the electrochemical behavior of functionalized MWCNTs. Chorono Amperometry (CA) monitoring for catalytic oxidation of the analyte was done at an potential of −0.26V vs. Ag/AgCl necessary to oxidize or reduce the H2O2 with minimal interference from the possible coexisting electroactive compounds. EDA-MWCNT/GCE combination shows good sensing response compared with pristine, DMA and TEA functionalized MWCNTs. The CA signals are linearly proportional to the concentration of H2O2 up to 9.9 × 10−6 M with remarkable response time (<5 sec). The H2O2 sensitivity for amine functionalized nanotubes is in the order of EDA (525.8 mA · μM−1· cm−2) > DMA (199.75 mA·μM−1·cm−2) > TEA (176.63 mA·μM−1·cm−2). The results of analysis reveals that, the chemical structure and surface charge associated with amine functionalization plays an important role in electrochemical behavior of MWCNTs.

Solar Exfoliated Graphene and its Application in Supercapacitors and Electrochemical H2O2 Sensing

In the present study, graphene nanosheets are synthesized using sunlight irradiation focussed onto graphite oxide. The morphological characteristics of graphene are examined using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Raman spectroscopy and X-ray diffraction (XRD) are used for the structural characterization of the sample. The electrochemical performance is evaluated using cyclic voltammetry (CV), charge-discharge characteristics and impedance spectroscopy. A high specific capacitance value of 223Fg−1 is obtained using cyclic voltammetry. The electrochemical detection of H2O2, a common biological species using solar graphene is demonstrated. The impedance spectroscopy and CV are used to study the electrocatalytic activity of the material. High sensitivity of 64.79μAmM−1cm−2 is reported.