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1.
We report on a simple and rapid method for the preparation of a disposable palladium nanoparticle-modified graphite pencil electrode (PdNP-GPE) for sensing hydrogen peroxide (H2O2). The bare and PdNP-modified GPEs were characterized by cyclic voltammetry and SEM. The two electrodes displayed distinct electrocatalytic activities in response to the electrochemical reduction of H2O2. The amperometric detection limits were 45 nM and 0.58 mM, respectively, for the PdNP-GPE and bare-GPE, at an S/N of 3. The electrodes can be prepared simply and at low cost, and represent a promising tool for sensing H2O2. Figure
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2.
We have prepared a novel sensor for hydrogen peroxide that is based on a glassy carbon electrode modified with a film containing multi-walled carbon nanotubes wired to CuO nanoflowers. The nanoflowers were characterized by X-ray powder diffraction, and the electrode was characterized by cyclic voltammetry (CV) and scanning electron microscopy. The response of the modified electrode towards hydrogen peroxide was investigated by CV and chronoamperometry and showed it to exhibit high electrocatalytic activity, with a linear range from 0.5?μM to 82?μM and a detection limit of 0.16?μM. The sensor also displays excellent selectivity and stability. Graphical abstract
We have prepared a novel sensor for hydrogen peroxide (H2O2) that is based on a glassy carbon electrode modified with a film containing multi-walled carbon nanotubes (MWCNTs) wired to CuO nanoflowers. The scheme shows the construction of the MWCNTs-wired CuO nanoflowers modified electrode and electrocatalytic activity towards H2O2. When H2O2 was added, the cathodic peak current of the CuO-MWCNTs/GCE remarkably increased while its anodic peak current obviously decreased. By increasing the concentration of H2O2, the cathodic peak current further increased while its anodic peak current further decreased. Indicating CuO-MWCNTs/GCE has a remarkable electrocatalytic activity for H2O2. The scheme. The construction of the MWCNTs-wired CuO nanoflowers modified electrode and electrocatalytic activity towards H2O2 相似文献
3.
A sensor for hydrogen peroxide is described that is based on an indium tin oxide electrode modified with Fe3O4 magnetic nanoparticles which act as a mimic for the enzyme peroxidase and greatly improve the analytical performance of the sensor. The amperometric current is linearly related to the concentration of H2O2 in the range from 0.2 mM to 2 mM, the regression equation is y?=?-0.5–1.82x, the correlation coefficient is 0.998 (n?=?3), and the detection limit is 0.01 mM (S/N?=?3). The sensor exhibits favorable selectivity and excellent stability. Figure
Using the peroxidase mimic property of Fe3O4 magnetic nanoparticles (MNPs), a sensitive electrochemical method with favorable analytical performance for the determination of hydrogen peroxide (H2O2) was developed. 相似文献
4.
We have prepared a sol–gel that incorporates Prussian Blue (PB) as a redox mediator. It is shown that the PB in the pores of the sol–gel retains its electrochemical activity and is protected from degradation at acidic and neutral pH values. TEM and EDX studies revealed the PB nanoparticles to possess a cubic crystal structure and to be well entrapped and uniformly dispersed in the pores of the matrix. The electrocatalytic activity of the materials toward hydrogen peroxide (H2O2) was studied by cyclic voltammetry and amperometry. The modified electrode displays good sensitivity for the electrocatalytic reduction of H2O2 both in acidic (pH 1.4) and neutral media. The sensor has a dynamic range from 3 to 210 μM of H2O2, and the detection limit is 0.6 μM (at an SNR of 3). Figure
TEM micrograph of the Sol-gel–PB composite showing a large quantity of crystalline cubic nanoparticles uniformly distributed in the sol-gel matrix and electrocatalytic response of the Sol-gel–PB electrode for hydrogen peroxide. 相似文献
5.
Yang Liu Gengzhi Sun Chunbo Jiang Xin Ting Zheng Lianxi Zheng Chang Ming Li 《Mikrochimica acta》2014,181(1-2):63-70
We report on a carbon nanotube (CNT) fiber microelectrode coated with palladium nanoparticles (PdNPs) and enabling electrochemical sensing of hydrogen peroxide (H2O2). The synergistic effects of the CNT fibers (good mechanical strength and large surface area) and of the PdNPs (high electrocatalytic activity) result in a microelectrode for H2O2 that exhibits a 2-s response time, a detection limit as low as 2 μM, a sensitivity of 2.75 A cm?2 M?1, and a linear response range from 2 μM to 1.3 mM (R?=?0.9994). The sensor is also selective and not interfered by potentially competing species in biological fluids, thus representing an inexpensive but highly sensitive and selective microsensor for H2O2. Figure
Images ofthe palladium nanoparticle-coated carbon nanotube (PdNP/CNT) fiber microelectrode (left) and its amperometric response to hydrogen peroxide (H2O2) with different concentrations (right) 相似文献
6.
We report on a nano-array sensor for hydrogen peroxide (H2O2) that is based on a nanoporous anodic aluminum oxide template. This was used as a matrix for the co-immobilization of horseradish peroxidase (HRP) and methylene blue (MB) on the surface of an indium tin oxide electrode. The immobilized HRP retained its natural activity and MB is capable of efficiently shuttle electrons between HRP and the electrode. The new electrode was characterized by SEM and electrochemical methods. It exhibits fast response, long-term stability, high sensitivity and good selectivity to H2O2. Under optimized conditions, it linearly responds to H2O2 in the concentration range from 1.0?μM to 26?mM, with a detection limit of 0.21?μM (at S/N?=?3). Figure
A nano-array biosensor for hydrogen peroxide (H2O2) based on the co-electrodeposition of horseradish peroxidase (HRP) and methylene blue (MB) into anodic aluminum oxide template was constructed. The immobilized HRP could maintain natural bioactivity and MB could efficiently shuttle electrons between HRP and the electrode. 相似文献
7.
A biosensor for hydrogen peroxide was constructed by immobilizing horseradish peroxidase on chitosan-wrapped NiFe2O4 nanoparticles on a glassy carbon electrode (GCE). The electron mediator carboxyferrocene was also immobilized on the surface of the GCE. UV?Cvis spectra, Fourier transform IR spectra, scanning electron microscopy, and electrochemical impedance spectra were acquired to characterize the biosensor. The experimental conditions were studied and optimized. The biosensor responds linearly to H2O2 in the range from 1.0?×?10?5 to 2.0?×?10?3?M and with a detection limit of 2.0?×?10?6?M (at S/N?=?3). Figure
A biosensor for hydrogen peroxide was constructed by immobilizing horseradish peroxidase on chitosan-wrapped NiFe2O4 nanoparticles on a glassy carbon electrode. 相似文献
8.
Yingqiu Zhang Wenxiu Yang Yizhe Wang Jianbo Jia Jianguo Wang 《Mikrochimica acta》2013,180(11-12):1085-1091
A glassy carbon electrode was modified with PdO-NiO composite nanofibers (PdO-NiO-NFs) and applied to the electrocatalytic reduction of hydrogen peroxide (H2O2). The PdO-NiO-NFs were synthesized by electrospinning and subsequent thermal treatment, and then characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Factors such as the composition and fraction of nanofibers, and of the applied potential were also studied. The sensor exhibits high sensitivity for H2O2 (583.43 μA?·?mM?1?·?cm?2), a wide linear range (from 5.0 μM to 19 mM), a low detection limit (2.94 μM at an SNR of 3), good long term stability, and is resistant to fouling. Figure
A glassy carbon electrode was modified with PdO-NiO composite nanofibers which were synthesized by electrospinning and subsequent thermal treatment. The sensor exhibited a wide linear range, high sensitivity, good stability and selectivity for the detection of hydrogen peroxide 相似文献
9.
Lucia Melnikova Kristyna Pospiskova Zuzana Mitroova Peter Kopcansky Ivo Safarik 《Mikrochimica acta》2014,181(3-4):295-301
Magnetoferritin is a spherical biomacromolecule with a diameter of about 12 nm. It consists of a protein shell composed of apoferritin that is surrounding magnetic nanoparticles of magnetite (Fe3O4) or maghemite (γ-Fe2O3). Magnetoferritins with various iron content (loading factor) were synthetically prepared and their peroxidase-like activities studied via the oxidation of the chromogenic substrate N,N-diethyl-p-phenylenediamine sulfate by hydrogen peroxide to give a purple product with an absorption maximum at 551 nm. Magnetoferritin with higher loading factor exhibits a higher peroxidase-like activity. The catalytic activity was successfully applied to the determination of hydrogen peroxide in the 5.8 to 88.2 mM concentration range. Figure
Change of substrate colour in the presence of hydrogen peroxide due to the peroxidase-like activity of magnetoferritin. 相似文献
10.
We report on a novel hydrogen peroxide biosensor that was fabricated by the layer-by-layer deposition method. Thionine was first deposited on a glassy carbon electrode by two-step electropolymerization to form a positively charged surface. The negatively charged gold nanoparticles and positively charged horseradish peroxidase were then immobilized onto the electrode via electrostatic adsorption. The sequential deposition process was characterized using electrochemical impedance spectroscopy by monitoring the impedance change of the electrode surface during the construction process. The electrochemical behaviour of the modified electrode and its response to hydrogen peroxide were studied by cyclic voltammetry. The effects of the experimental variables on the amperometric determination of H2O2 such as solution pH and applied potential were investigated for optimum analytical performance. Under the optimized conditions, the biosensor exhibited linear response to H2O2 in the concentration ranges from 0.20 to 1.6?mM and 1.6 to 4.0?mM, with a detection limit of 0.067?mM (at an S/N of 3). In addition, the stability and reproducibility of this biosensor was also evaluated and gave satisfactory results. Figure
A novel hydrogen peroxide biosensor was fabricated via layer-by-layer depositing approach. Thionine was first deposited on a glassy carbon electrode by electropolymerization to form a positively charged surface (PTH). Negatively charged gold nanoparticles (NPs) and positively charged horseradish peroxidase (HRP) were then immobilized onto the electrode via electrostatic adsorption. 相似文献
11.
Qian-Li Zhang Ai-Jun Wang Zi-Yan Meng Ya-Hui Lu Hong-Jun Lin Jiu-Ju Feng 《Mikrochimica acta》2013,180(7-8):581-587
We have prepared porous and network-like nanofilms of gold by galvanic replacement of a layer of copper particles acting as a template. The films were first characterized by scanning electron microscopy and X-ray diffraction, and then modified with cysteamine so to enable the covalent immobilization of the enzyme microperoxidase-11. The immobilized enzyme undergoes direct electron transfer to the underlying electrodes, and the electrode displays high electrocatalytic activity towards the reduction of oxygen and hydrogen peroxide, respectively, owing to the largely enhanced electroactive surface of the porous gold film. The detection limit of H2O2 is 0.4 μM (3 S/N). Figure
In this work, porous network-like Au films were prepared by galvanic replacement using Cu film as a sacrificial template. The cysteamine modified Au film was used to immobilize microperoxidase-11, which showed good stability and excellent electrochemical performance towards the reduction of O2 and H2O2, respectively 相似文献
12.
Ying Wang Kun Qian Kai Guo Jilie Kong Jean-Louis Marty Chengzhong Yu Baohong Liu 《Mikrochimica acta》2011,175(1-2):87-95
An amperometric biosensor for hydrogen peroxide (H2O2) has been constructed by immobilizing cytochrome c on an indium/tin oxide (ITO) electrode modified with a macroporous material. Cyclic voltammetry showed that the direct and quasi-reversible electron transfer of cytochrome c proceeds without the need for an electron mediator. A surface-controlled electron transfer process can be observed with an apparent heterogeneous electron-transfer rate constant (ks) of 29.2?s?1. The biosensor displays excellent electrocatalytic responses to the reduction of H2O2 to give amperometric responses that increase steadily with the concentration of H2O2 in the range from 5???M to 2?mM. The detection limit is 0.61???M at pH?7.4. The apparent Michaelis-Menten constant (Km) of the biosensor is 1.06?mM. This investigation not only provided a method for the direct electron transfer of cytochrome c on macroporous materials, but also established a feasible approach for durable and reliable detection of H2O2. Figure
Biosensor for hydrogen peroxide was developed by immobilizing cytochrome c in the macroporous ordered silica foam (MOSF) through the electrostatic interaction. The achievement of the direct electron transfer between cytochrome c and electrode surface indicated that the MOSF modified electrode displayed good affinity and biocompatibility for cytochrome c. 相似文献
13.
Fenfen Liang Chenyao Liu Jiao Jiao Shuoqi Li Ji Xia Jingbo Hu 《Mikrochimica acta》2012,176(3-4):389-395
We report on a non-enzymatic amperometric sensor for hydrogen peroxide (H2O2). It was fabricated by electrodeposition of multi-wall carbon nanotubes and polyaniline along with platinum nanoparticles on the surface of a glassy carbon electrode. The modification was probed by scanning electron microscopy and cyclic voltammetry. The resulting sensor exhibits a high sensitivity (748.4?μA·mM?1·cm?2), a wide linear range (7.0?μM–2.5?mM), a low detection limit (2.0?μM) (S/N?=?3), a short response time (>5?s), and long-term stability, and is not interfered by common species. It was successfully applied to determine H2O2 in disinfectants. Figure
SEM images of the obtained Pt/MWCNTs-PANI composite films with large surface-to-volume ratio and biocompatibility 相似文献
14.
Fe3O4 nanoparticles were deposited on sheets of graphene oxide (GO) by a precipitation method, and glucose oxidase (GOx) was then immobilized on this material to produce a GOx/Fe3O4/GO magnetic nanocomposite containing crosslinked enzyme clusters. The 3-component composite functions as a binary enzyme that was employed in a photometric method for the determination of glucose and hydrogen peroxide where the GOx/Fe3O4/GO nanoparticles cause the generation of H2O2 which, in turn, oxidize the substrate N,N-diethyl-p-phenylenediamine to form a purple product with an absorption maximum at 550 nm. The absorbance at 550 nm can be correlated to the concentration of glucose and/or hydrogen peroxide. Under optimized conditions, the calibration plot is linear in the 0.5 to 600 μM glucose concentration range, and the detection limit is 0.2 μM. The respective plot for H2O2 ranges from 0.1 to 10 μM, and the detection limit is 0.04 μM. The method was successfully applied to the determination of glucose in human serum samples. The GOx/Fe3O4/GO nanoparticles are reusable. Figure
A one-step spectrophotometric method for the detection of glucose and/or H2O2 was developed by using GOx immobilized Fe3O4/GO MNPs as a bienzyme system and DPD as a substrate. 相似文献
15.
Rajshri K. Satvekar S. S. Rohiwal A. V. Raut V. A. Karande B. M. Tiwale S. H. Pawar 《Mikrochimica acta》2014,181(1-2):71-77
We report on a novel matrix of solgel organic–inorganic nanocomposite that was fabricated from silica sol gel and dextran. It was used for the immobilization of horseradish peroxidase (HRP) to give a biosensor for hydrogen peroxide (H2O2). The sensor film was characterized by Fourier transform infrared and UV–vis spectroscopy with respect to structural features and the conformation of the enzyme. The topographies of the surface of the electrode were investigated by field emission scanning electron microscopy. The biosensor was used to determine H2O2 quantitatively in the presence of Methylene blue as a mediator with high electron transfer efficiency. A pair of stable and well defined quasi-reversible redox peaks of the HRP [Fe (III)]/HRP [Fe (II)] redox couple was observed at pH 7.0. The biosensor responds to H2O2 in the 0.5 mM to 16.5 mM concentration range, and the limit of detection is 0.5 mM. Figure
A synthesized novel silica-dextran nanocomposite provides three dimensional interfaces for immobilization of HRP which maintains the characteristic structure and enhances the catalytic activity. 相似文献
16.
We have developed a 3-dimensional (3-D) electrochemical sensor for highly sensitive detection of hydrogen peroxide (H2O2). Porous 3-D carbon nanofibers (CNFs), prepared by electrospinning, served as scaffold on a glassy carbon electrode. The 3-D CNFs were functionalized with platinum nanoparticles (Pt-NPs) by in-situ gas-phase decomposition of platinum salts at high temperature. The Pt-NPs act as an electrocatalyst for the decomposition of H2O2. TEM revealed that large amounts of Pt-NPs are deposited in the electrospun CNFs electrode even without using any stabilizer or reducing reagent. The sensor was investigated by cyclic voltammetry and amperometry and displays a good response to H2O2 with a linear range between 10 μM and 15 mM (R?=?0.9994), a low detection limit (3.4 μM at a signal-to-noise ratio of 3), and a response time of 3 s. The sensor shows excellent stability and selectivity. Figure
We report the direct growth of the Pt NPs in the 3-D CNFs via electrospinning and sequent thermal treatment. We demonstrate the use of 3-D architecture novel Pt/CNFs electrode for nonenzymatic electrochemical sensing of H2O2. The sensor shows outstanding performance in terms of detection range, detection limit, response time, stability and selectivity. 相似文献
17.
Su-Juan Li Ji-Min Du Jia-Ping Zhang Meng-Jie Zhang Jing Chen 《Mikrochimica acta》2014,181(5-6):631-638
We have prepared a graphene-based hybrid nanomaterial by electrochemical deposition of cobalt oxide nanoparticles (CoOxNPs) on the surface of electrochemically reduced graphene oxide deposited on a glassy carbon electrode (GCE). Scanning electron microscopy and cyclic voltammetry were used to characterize the immobilized nanoparticles. Electrochemical determination of H2O2 is demonstrated with the modified GCE at pH 7. Compared to GCEs modified with CoOxNPs or graphene sheets only, the new electrode displays larger oxidative current response to H2O2, probably due to the synergistic effects between the graphene sheets and the CoOxNPs. The sensor responds to H2O2 with a sensitivity of 148.6 μA mM?1 cm?2 and a linear response range from 5 μM to 1 mM. The detection limit is 0.2 μM at a signal to noise ratio (SNR) of three. The method was successfully applied to the determination of H2O2 in hydrogen peroxide samples. Figure
A highly sensitive H2O2 sensor using a glassy carbon electrode modified with cobalt oxide nanoparticles/electrochemical reduced graphene oxide (CoOxNPs/ERGO) hybrids is presented. 相似文献
18.
Zhongke Yan Jianwei Zhao Lirong Qin Fan Mu Ping Wang Xining Feng 《Mikrochimica acta》2013,180(1-2):145-150
Granular nanowires with a diameter of about 60 nm were fabricated from cuprous oxide (Cu2O) by an electrochemical method using anodic aluminium oxide as the template. A non-enzymatic sensor for hydrogen peroxide (H2O2) was then developed on the basis of a gold electrode modified with Cu2O nanowires and Nafion. The resulting sensor enables the determination of H2O2 with a sensitivity of 745 μA?mM?1?cm?2, over a wide linear range (0.25 μM to 5.0 mM), and with a low detection limit (0.12 μM). The results demonstrate that the use of such granular nanowires provides a promising tool for the design of non-enzymatic chemical sensors. Figure
A non-enzymatic sensor for hydrogen peroxide (H2O2) was developed on the basis of a gold electrode modified with Cu2O nanowires and Nafion. The resulting sensor enables the determination of H2O2 with a sensitivity of 745 μA mM?1 cm?2, over a wide linear range (0.25 μM to 5.0 mM), and with a low detection limit (0.12 μM). The results demonstrate that the use of such granular nanowires provides a promising tool for the design of non-enzymatic chemical sensors 相似文献
19.
Yuling Cui Bing Zhang Bingqian Liu Huafeng Chen Guonan Chen Dianping Tang 《Mikrochimica acta》2011,174(1-2):137-144
We report on a new electrochemical biosensing strategy for the sensitive detection of hydrogen peroxide (H2O2) in foodstuff samples. It is based on a gold electrode modified with layer of graphene patterned with a multilayer made from an organic?Cinorganic hybrid nanomaterial. Initially, a layer of thionine (Th) was assembled on the surface of the graphene nanosheets, and these were then cast on the surface of the electrode for the alternate assembly of gold nanoparticles and horseradish peroxidase. The large surface-to-volume ratio and high conductivity of the nanosheets provides a benign microenvironment for the construction of the biosensor. The use of such a multilayer not only shortens the electron transfer pathway of the active center of the enzyme due to the presence of gold nanoparticles, but also enhances the electrocatalytic efficiency of the biosensor toward the reduction of H2O2. The electrochemical characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. The number of layers, the operating potential, and the pH of the supporting electrolyte were optimized. Linear response is obtained for the range from 0.5???M to 1.8?mM of H2O2, the detection limit is 10 nM (at S/N?=?3), and 95% of the steady-state current is reached within 2?s. The method was applied to sense H2O2 in spiked sterilized milk and correlated excellently with the permanganate titration method.
A new electrochemical biosensing strategy for sensitive detection of hydrogen peroxide in foodstuff was developed by using a gold electrode modified with a layer of graphene nanosheets patterned with a multilayer made from an organic?Cinorganic hybrid nanomaterial. 相似文献
20.
Water-soluble cadmium telluride quantum dots (CdTe QDs) capped with glutathione (GSH) display chemiluminescence (CL) emission on reaction with hydrogen peroxide (H2O2) in strongly alkaline medium. It is found that the CL is strongly enhanced on addition of formaldehyde in aqueous solution. A flow injection system was developed, and it is shown that there is good linearity between CL intensity and the concentration of formaldehyde in the 0.06–3.0 μg L?1 range. The limit of detection is as low as 10 ng L?1. The method was successfully applied to the determination of formaldehyde in indoor air after adsorption into an aqueous phase. The recoveries for the real samples range from 97 % to 102.5 %, and the relative standard deviation is <3.8 % for intra- and inter-assay precision. Figure
Formaldehyde enhances the CL resulting from CdTe quantum dots and H2O2, and this effect is exploited in a simple and sensitive FIA method for the determination of formaldehyde. 相似文献