Electrodeposited Silver Nanoparticles on Carbon Ionic Liquid Electrode for Electrocatalytic Sensing of Hydrogen Peroxide

Silver nanoparticles (narrowly dispersed in diameter) were electrodeposited on carbon ionic liquid electrode (CILE) surface using a two‐step potentiostatic method. Potentiostatic double pulse technique was used as a suitable and simple method for controlling the size and morphologies of silver nanoparticles electrodeposited on CILE. The obtained silver nanoparticles deposited on CILE surface showed excellent electrocatalytic activity (low overpotential of ?0.35 V vs. Ag/AgCl) towards reduction of hydrogen peroxide. A linear dynamic range of 2–200 μM with an experimental detection limit of 0.7 μM (S/N=3) and reproducibility of 4.1% (n=5) make the constructed sensor suitable for peroxide determination in aqueous solutions.     

Gold Nanoparticles Electrodeposited on Ordered Mesoporous Carbon as an Enhanced Material for Nonenzymatic Hydrogen Peroxide Sensor

A facile and controllable electrodeposition method was developed to directly attach gold nanoparticles (GNPs) on ordered mesoporous carbon (OMC). The GNPs on OMC substrate were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and X‐ray photoelectron spectrometer (XPS), respectively. A nonenzymatic hydrogen peroxide (H₂O₂) sensor was fabricated on GNPs‐OMC/GCE. The sensor demonstrated a fast amperometric response (2.5 s), a wide linear range toward H₂O₂ concentrations between 2.0×10^?6 and 3.92×10^?3 M (R=0.999), and a low detection limit of 0.49 µM (S/N=3). Moreover, it exhibited good reproducibility and long‐term stability. The excellent electrocatalytical activity might be attributed to the synergistic effect of OMC and GNPs.     

Novel Nonenzymatic Hydrogen Peroxide Sensor Based on Ag/Cu2O Nanocomposites

The nanocomposites of Ag nanoparticles supported on Cu₂O were prepared and used for fabricating a novel nonenzymatic H₂O₂ sensor. The morphology and composition of the nanocomposites were characterized using the scanning electron microscope (SEM), transmission electron microscope (TEM), energy‐dispersive X‐ray spectrum (EDX) and X‐ray diffraction spectrum (XRD). The electrochemical investigations indicate that the sensor possesses an excellent performance toward H₂O₂. The linear range is estimated to be from 2.0 μM to 13.0 mM with a sensitivity of 88.9 μA mM^?1 cm^?2, a response time of 3 s and a low detection limit of 0.7 μM at a signal‐to‐noise ratio of 3. Additionally, the sensor exhibits good anti‐interference.     

Amperometric Biosensor for Hydrogen Peroxide Based on Electrodeposited Sub-micrometer Gold Modified Glassy Carbon Electrode

IntroductionAmperometricbiosensorofhydrogenperoxideisofpracticalimportancebecauseofitswideapplicationsinchemical,biological,clinical,environmentalandmanyotherfields.Forimprovementofsensor抯quality,vari-ouskindsofchemicalmodificationmethodshavebeendevelopedforreducingredoxoverpotentialsofH2O2atelectrodesurfaces,increasingthedetectionsensitivity,linearrange,stabilityandlivetime.Ithasbeenshownthattheuseofsub-micrometersizedmetalparticlessuchasPt-blackcansignificantlyimprovethequalityofthebiosens…     

基于聚苯胺-纳米金修饰玻碳电极的研制及其对过氧化氢的催化研究

通过将纳米金固载在聚苯胺(PANI)修饰的玻碳电极(GCE)上而研制出一种新型过氧化氢(H2O2)传感器。首先将苯胺单体电聚合到表面干净的裸GCE上,再将制备好的PANI/GCE浸入纳米金溶胶中,通过静电吸附将纳米金固载于PANI之上。整个制备过程通过扫描电子显微镜(SEM)进行观测。SEM图片显示16nm的纳米金均匀地分散在PANI膜上。被吸附的纳米金对H2O2的还原有良好的电催化活性。在优化的实验条件下,该传感器对H2O2测定的线性范围为1.2μmol/L~0.55mmol/L;检出限为0.35μmol/L(S/N=3)。该传感器具有响应快、灵敏度高、稳定性好的特点。     

Novel Electrochemical Microsensor for Hydrogen Peroxide based on Iron‐Ruthenium Hexacyanoferrate Modified Carbon Fiber Electrode

Novel electrochemical microsensor based on mixed iron‐ruthenium hexacyanoferrate (FeRuHCF) modified carbon fiber microelectrode (CFME) is presented for voltammetric and amperometric measurement of hydrogen peroxide at physiological pH. The FeRuHCF coating was electrochemically deposited using a one step procedure onto the substrate carbon fiber microelectrode by cycling the potential between 0.0 and +1.0 V (vs. Ag/AgCl) in a solution containing all precursor salts. The microsensor displayed good stability in neutral and alkaline media and had a nonstop working lifetime of up to 12 hours. The amperometric response time varied from 5 to 15 s depending on the hydrogen peroxide concentration level. The newly developed electrochemical microsensor exhibited a highly linear behavior in the examined concentration range from 5 to 1000 μmol L^?1 (R²=0.999), an LoD (3σ) of 0.9 μmol L^?1, and a favorable reproducibility with a calculated RSD of 2.9% (n= 6) for 100 μmol L^?1 hydrogen peroxide, thus holding great promise for its further application in real samples and its exploitation in combination with biorecognition elements in advanced microbiosensor design.     

A Hydrogen Peroxide Sensor Based on Silver Nanoparticles Biosynthesized by Bacillus subtilis

In this study, silver nanoparticles （AgNPs） were biosynthesized by Bacillus subtilis and used to construct a nonenzymatic hydrogen peroxide （H202） sensor, Scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy confirmed that the AgNPs were prepared successfully with spherical morphol- ogy. The electrochemical properties of the resulted sensor were investigated by cyclic voltammetry, chronoam- perometry and electrochemical impedance spectroscopy. It was found that the sensor exhibited good electrocatalytic activity towards H202 reduction with a wider linear range from 0.05 to 120 mmol.L-1, a detection limit of 8 gmol.L-1 and a fast response time less than 2 s. The sensor exhibited good selectivity for H202 determination in the presence of glucose, acetaminophen, ascorbic acid and uric acid.     

Immobilization of Enzymes on the Nano‐Au Film Modified Glassy Carbon Electrode for the Determination of Hydrogen Peroxide and Glucose

A new enzyme‐based amperometric biosensor for hydrogen peroxide was developed relying on the efficient immobilization of horseradish peroxidase (HRP) to a nano‐scaled particulate gold (nano‐Au) film modified glassy carbon electrode (GC). The nano‐Au film was obtained by a chitosan film which was first formed on the surface of GC. The high affinity of chitosan for nano‐Au associated with its amino groups resulted in the formation of nano‐Au film on the surface of GC. The film formed served as an intermediator to retain high efficient and stable immobilization of the enzyme. H₂O₂ was detected using hydroquinone as an electron mediator to transfer electrons between the electrode and HRP. The HRP immobilized on nano‐Au film maintained excellent electrocatalytical activity to the reduction of H₂O₂. The experimental parameters such as the operating potential of the working electrode, mediator concentration and pH of background electrolyte were optimized for best analytical performance of amperometry. The linear range of detection for H₂O₂ is from 6.1×10^?6 to 1.8×10^?3 mol L^?1 with a detection limit of 6.1 μmol L^?1 based on signal/noise=3. The proposed HRP enzyme sensor has the features of high sensitivity (0.25 Almol^?1cm^?2), fast response time (t_90%≤10 s) and a long‐term stability (>1 month). As an extension, glucose oxidase (GOD) was chemically bound to HRP‐modified electrode. A GOD/HRP bienzyme‐modified electrode formed in this way can be applied to the determination of glucose with satisfactory performance.     

Prussian Blue Nanoparticles Self Assembling on Electrochemically Reduced Graphene Oxide Modified GC Electrode for Sensitive Hydrogen Peroxide Detection

A facile, fast, and convenient route was suggested for the fabrication of Prussian blue nano particles (PBNPs) assembled on reduced graphene oxide (RGO) modified glassy carbon electrode (PBNPs|RGO|GCE). RGO was electrodeposited on the surface of GCE and the prepared RGO|GCE was immersed into a ferric‐hexacyanoferrate(III) solution and PBNPs were assembled on the RGO|GCE for a certain period of time. The PBNPs film thickness can be easily controlled by adjusting the assembling duration. The developed PBNPs|RGO|GCE was successfully used for determining hydrogen peroxide, with a linear response over the concentration range 0.5‐400 μM, a good accuracy and precision, detection limit 0.44 μM, and sensitivity 1168 mA M^?1 cm^?2.     

Highly Sensitive Electrochemical Hydrogen Peroxide Sensor Based on Iron Oxide‐Reduced Graphene Oxide‐Chitosan Modified with DNA‐Celestine Blue

The present study describes a novel and very sensitive electrochemical assay for determination of hydrogen peroxide (H₂O₂) based on synergistic effects of reduced graphene oxide‐ magnetic iron oxide nanocomposite (rGO‐Fe₃O₄) and celestine blue (CB) for electrochemical reduction of H₂O₂. rGO‐Fe₃O₄ nanocomposite was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X‐ray diffraction (XRD), electrochemical impedance spectroscopy and cyclic voltammetry. Chitosan (Chit) was used for immobilization of amino‐terminated single‐stranded DNA (ss‐DNA) molecules via a glutaraldehyde (GA) to the surface of rGO‐Fe₃O₄. The MTT (3‐(4,5‐Dim ethylt hiazol‐2‐yl)‐2,5‐diphenylt etrazolium bromide) results confirmed the biocompatibility of nanocomposite. Experimental parameters affecting the ss‐DNA molecules immobilization were optimized. Finally, by accumulation of the CB on the surface of the rGO‐Fe₃O₄‐Chit/ssDNA, very sensitive amperometric H₂O₂ sensor was fabricated. The electrocatalytic activity of the rGO‐Fe₃O₄‐Chit/DNA‐CB electrode toward H₂O₂ reduction was found to be very efficient, yielding very low detection limit (DL) of 42 nM and a sensitivity of 8.51 μA/μM. Result shows that complex matrices of the human serum samples did not interfere with the fabricated sensor. The developed sensor provided significant advantages in terms of low detection limit, high stability and good reproducibility for detection of H₂O₂ in comparison with recently reported electrochemical H₂O₂ sensors.     

Trace Level Determination of Hydrogen Peroxide at a Carbon Ceramic Electrode Modified with Copper Oxide Nanostructures

An electrochemical sensor was developed for determination of hydrogen peroxide based on nanocopper oxides modified carbon sol‐gel or carbon ceramic electrode (CCE). The modified electrode was prepared by electrodeposition of metallic copper on the CCE surface and derivatized in situ to copper oxides nanostructures and characterized by scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques. The modified electrode responded linearly to the hydrogen peroxide (H₂O₂) concentration over the range 0.78–193.98 µmol L^?1 with a detection limit of 71 nmol L^?1 (S/N=3) and the sensitivity of 0.697 A mol^?1 L cm^?2. This electrode was used as selective amperometric sensor for determination of H₂O₂ contents in hair coloring creams.     

A Novel Hydrogen Peroxide Biosensor Based on Adsorption of Horseradish Peroxidase onto a Nanobiomaterial Composite Modified Glassy Carbon Electrode

In this work, a novel hydrogen peroxide biosensor derived from maize tassel (MT) and multiwalled carbon nanotube (MWCNT) composite was used to adsorb horseradish peroxidase (HRP) onto the surface of a glassy carbon electrode through electrostatic interactions. The morphology and structure of the products were characterized by SEM, FTIR and UV‐visible spectroscopy. The electrochemical and electrocatalytic performance of the HRP/MT‐MWCNT/GCE was studied using voltammetric and amperometric methods. The amperometric response of the biosensor varied linearly with concentration of H₂O₂ from 9 µM to 1 mM with detection limit of 4.0 µM (S/N=3). Furthermore, the biosensor exhibited good reproducibility and stability.     

磁性印迹纳米粒子固定血红蛋白修饰磁性电极构建过氧化氢传感器

采用表面印迹技术,以磁性二氧化硅纳米粒子（Fe₃O₄@SiO₂ NPs）作为载体、血红蛋白（Hb）为模板分子、正硅酸乙酯（TEOS）为印迹聚合物单体,制备了Hb印迹Fe₃O₄@SiO₂的磁性印迹纳米粒子（MMIPs NPs）. MMIPs NPs具有磁性内核和血红蛋白印迹壳层的核壳结构,可以富集并固定Hb. 使用壳聚糖将MMIPs NPs固定于磁性电极表面,构建血红蛋白类酶生物传感器,研究了Hb对过氧化氢（H₂O₂）的催化活性. MMIPS NPS相比于磁性非印迹纳米粒子（MNIPS NPS）,催化电流增加了14.3%. 采用磁性电极,MMIPS NPS、Hb和O₂的顺磁性使得该类酶生物传感器对H₂O₂的催化电流增加了60.0%. 血红蛋白类酶生物传感器电流响应与H₂O₂浓度在25 ~ 200 μmol·L^-1间呈线性关系,检出限为3 μmol·L^-1（S/N=3）,表明该类酶传感器对H₂O₂具有良好的催化性能.     

A Non‐Enzymatic Hydrogen Peroxide Sensor Based on Ag/MnOOH Nanocomposites

A novel non‐enzymatic sensor based on Ag/MnOOH nanocomposites was developed for the detection of hydrogen peroxide (H₂O₂). The H₂O₂ sensor was fabricated by immobilizing Ag/MnOOH nanocomposites on a glassy carbon electrode (GCE). The morphology and composition of the sensor surface were characterized using scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, transmission electron microscopy and X‐ray diffraction spectroscopy. The electrochemical investigation of the sensor indicates that it possesses an excellent electrocatalytic property for H₂O₂, and could detect H₂O₂ in a linear range from 5.0 µM to 12.8 mM with a detection limit of 1.5 µM at a signal‐to‐noise ratio of 3, a response time of 2 s and a sensitivity of 32.57 µA mM^?1 cm^?2. Additionally, the sensor exhibits good anti‐interference. The good analytical performance, low cost and straightforward preparation method made this novel electrode material promising for the development of effective non‐enzymatic H₂O₂ sensor.     

Methylene Blue/Multiwall Carbon Nanotube Modified Electrode for the Amperometric Determination of Hydrogen Peroxide

A novel amperometric sensor based on the incorporation of multiwalled carbon nanotubes (MWCNT) into a poly(methylene blue) (PMB) film immobilized on carbon composite electrodes is described. Cyclic voltammetry indicated that at a surface covered by a MWCNT/PMB layer the cathodic reduction of hydrogen peroxide is facilitated and occurs already at 0.0 V versus SCE. The effect of the order of deposition of PMB and MWCNT, as well as its loading, on electrochemical behaviour was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy. The influence of the various immobilised platforms on the electrocatalytic performance towards hydrogen peroxide was also examined.     

基于碳复合Fe3O4纳米粒子的过氧化氢电化学传感器研究

本文以碳纳米粒子复合Fe₃O₄磁性纳米粒子构建新型过氧化氢电化学传感器,该传感器对过氧化氢有良好的电催化性能,过氧化氢浓度在1.00×10^-6 ~ 1.00×10^-3 mol·L^-1范围内与其氧化峰电流之间呈良好线性关系(R = 0.9980),检出限为6.60×10^-7 mol·L^-1. 该传感器具有良好的抗干扰能力、较高的重现性和稳定性.     

Enhanced Hydrogen Peroxide Sensing Based on Tetraruthenated Porphyrins/Nafion/Glassy Carbon‐modified Electrodes via Incorporating of Carbon Nanotubes

The incorporation of carbon nanotubes to a Nafion/tetraruthenated cobalt porphyrin/ glassy carbon electrode (GC/Nf/CoTRP vs GC/Nf/CNTCoTRP) enhanced the amperometric determination of hydrogen peroxide. Both electrodes produced a decrease in the overpotential required for the hydrogen peroxide oxidation in about 100 mV compared to glassy carbon under the same experimental conditions. Nevertheless, for GC/Nf/CNT/CoTRP, the increase in the current is remarkable. The GC/Nf/CoTRP modified electrode gave no significant analitycal signal for hydrogen peroxide reduction. Moreover, a great increase in current is observed with GC/Nf/CNT/CoTRP at ?150mV which suggests a significant increase in the sensitivity of the modified electrode. Scanning electrochemical microscopy (SECM) revealed an enhancement in the electroactivity of the GC/Nf/CNT/CoTRP modified electrode. This fact has been explained in terms of enhanced homogeneity of the electrodic surface as a consecuence of better dispersibility of CNT‐CoTRP produced by a Nafion polyelectrolyte.     

Immobilization of Hemoglobin on the Gold Colloid Modified Pretreated Glassy Carbon Electrode for Preparing a Novel Hydrogen Peroxide Biosensor

A novel hydrogen peroxide (H₂O₂) biosensor was developed by immobilizing hemoglobin on the gold colloid modified electrochemical pretreated glassy carbon electrode (PGCE) via the bridging of an ethylenediamine monolayer. This biosensor was characterized by UV-vis reflection spectroscopy (UV-vis), electrochemical impendence spectroscopy (EIS) and cyclic voltammetry (CV). The immobilized Hb exhibited excellent electrocatalytic activity for hydrogen peroxide. The Michaelis–Menten constant (K _m) was 3.6 mM. The currents were proportional to the H₂O₂ concentration from 2.6 × 10⁻⁷ to 7.0 × 10⁻³ M, and the detection limit was as low as 1.0 × 10⁻⁷ M (S/N = 3).     

碳纳米管负载纳米铂修饰电极及电催化氧化H2O2的研究

采用化学气相沉积法在碳纳米管(CNT)上负载Pt纳米颗粒,并制备了CNT-Pt修饰玻碳电极(CNT-Pt/GCE).研究了该修饰电极在磷酸缓冲液中对H2O2的电催化氧化作用以及实验条件的影响.计算了H2O2在CNT-Pt/GCE上的电极反应速率常数.结果表明,CNT-Pt/GCE对H2O2的电化学氧化具有良好的催化作用,电极反应速率常数比铂电极高约2.65倍.初步探讨了电催化氧化机理,为酶电化学传感器的研制提供了一条新的途径.     

Sensitive Electrochemical Determination of Hydrogen Peroxide Using Copper Nanoparticles in a Polyaniline Film on a Glassy Carbon Electrode

Rapid and accurate determination of hydrogen peroxide is necessary in biochemistry and environmental science. In this paper, a sensitive hydrogen peroxide electrochemical sensor was developed by cyclic voltammetry deposition of polyaniline–copper nanocomposite film on a glassy carbon electrode. The synthesized polyaniline/Cu composites were characterized by scanning electron microscopy and X-ray diffraction. With a typical working potential of 0.4?V (versus Ag/AgCl) and a pH value of 6.0, the prepared electrochemical sensor achieved linear range of 1.0–500?µM for hydrogen peroxide detection. A relative standard deviation of 4.9% for n?=?7 and 10.0?µM of H₂O₂ and a limit of detection of 0.33?µM at a signal-to-noise ratio?=?3 were observed. The sensor was successfully used for the analysis of tap water, and a spiked recovery of 93.0?±?2.1% was obtained, further confirming the sensor’s accuracy and feasibility.