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1.
Prussian blue nanoparticles (PBNPs) were prepared by a self‐assembly process on a glassy carbon electrode (GCE) modified with poly(o‐phenylenediamine) (PoPD) film. The stepwise fabrication process of PBNP‐modified PoPD/GCE was characterized using scanning electron microscopy and electrochemical impedance spectroscopy. The prepared PBNPs showed an average size of 70 nm and a homogeneous distribution on the surface of the modified electrode. The PBNPs/PoPD/GCE showed electrocatalytic activity towards the oxidation of pyridoxine (PN) and was used as an amperometric sensor. The modified electrode exhibited a linear response for PN oxidation over the concentration range 3–38.5 μM with a detection limit of ca 6.10 × 10?7 M (S/N = 3) and sensitivity of 2.79936 × 103 mA M?1 cm?2 using an amperometric method. The mechanism and kinetics of the catalytic oxidation reaction of PN were investigated using cyclic voltammetry and chronoamperometry. The values of α, kcat and D were estimated as 0.36, 1.089 × 102 M?1 s?1 and 8.9 × 10?5 cm2 s?1, respectively. This sensor also exhibited good anti‐interference and selectivity. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

2.
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.  相似文献   

3.
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.  相似文献   

4.
At present, a highly sensitive hydrogen peroxide (H2O2) sensor is fabricated by ferrocene based naphthaquinone derivatives as 2,3‐Diferrocenyl‐1,4‐naphthoquinone and 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone. These ferrocene based naphthaquinone derivatives are characterized by H‐NMR and C‐NMR. The electrochemical properties of these ferrocene based naphthaquinone are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) on modified glassy carbon electrode (GCE). The modified electrode with ferrocene based naphthaquinone derivatives exhibits an improved voltammetric response to the H2O2 redox reaction. 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone show excellent non‐enzymatic sensing ability towards H2O2 response with a detection limitation of 2.7 μmol/L a wide detection range from 10 μM to 400 μM in H2O2 detection. The sensor also exhibits short response time (1 s) and good sensitivity of 71.4 μA mM?1 cm?2 and stability. Furthermore, the DPV method exhibited very high sensitivity (18999 μA mM?1 cm?2) and low detection limit (0.66 μM) compared to the CA method. Ferrocene based naphthaquinone derivative based sensors have a lower cost and high stability. Thus, this novel non‐enzyme sensor has potential application in H2O2 detection.  相似文献   

5.
Exploration of new property/function of nanomaterials is always a strong impetus in the nanoscience field. Here, a new method of electrochemical conversion (ECC) of magnetic nanoparticles (MNPs) is proposed to endow MNPs with signal generation ability for sensing. Briefly, high potential was applied to split H2O to generate acid, while Fe3O4 MNPs reacted with H+ and produce ferric/ferrous ions, which further reacted with K4Fe(CN)6 to yield Prussian blue (PB) through potential cycling. The ECC method worked well on both home‐made and commercial MNPs with different sizes. The generated PB possessed strong electrochemical activity for further applications. Interestingly, an uneven deposition of PB on working electrode and undesired contamination of the reference and counter electrodes were found when using commercial integrated three‐electrode chip. A 3D‐printed electrochemical cell was designed to facilitate the ECC and avoid drawbacks of commercial integrated electrode. The 3D‐printed electrochemical cell was proven to solve the problem above through spatial separation of electrodes and thus facilitated the ECC process. An electrochemical sensor for H2O2 detection based on the catalysis ability of ECC‐based PB exhibited a linear response from 5 μM to 1 mM, a high sensitivity of 269 μA mM?1 cm?2 and a low detection limit of 0.16 μM (S/N=3), which suggests its promising application prospect in electrochemistry‐related analysis.  相似文献   

6.
Prussian blue nanoparticles (PBNPs) have peroxidase-like activity for H2O2. However, PB alone have poor electrochemical performances. Herein, a strategy was proposed by direct in-situ growth PBNPs onto gold nanowires (AuNWs) surface to obtain the peroxidase-like activity with about 4.05 times higher than that of PBNPs alone. PBNPs@AuNWs was employed to construct a non - enzymatic electrochemical H2O2 sensor with the detection limit of 5.3×10−9 mol/L (S/N=3). The sensor was successfully used to detect H2O2 in human serum samples or secreted from living HeLa cells. It may be a competitive candidate for H2O2 assaying in biological samples or cellular investigation.  相似文献   

7.
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.  相似文献   

8.
《Electroanalysis》2018,30(3):583-592
In this work, we present a simple and effective approach for fabricating sub‐micron structured gold (SM−Au) electrodes by chemically etching the magnetron co‐sputtered gold film in KI solution for certain time. Such electrodes with a large surface area to volume ratio were used as the matrix for electrochemical deposition of Prussian blue (PB) to develop an electrochemical hydrogen peroxide sensor. Experimental characterization using scanning electron microscope and atomic force microscope shows that the thickness of PB layer on SM−Au electrode is around 140 nm, and is composited with cubic PB nanocrystals. The electrochemical performance of the designed sensor, studied using cyclic voltammograms and chronoamperometry methods, suggests that the sensor based on SM−Au/PB electrode presents the direct electron transfer of PB particle towards SM−Au film, and exhibits fast response, wide linearity, low detection limit and high stability. Under the optimized conditions, the sensitivity of the developed sensor for the detection of H2O2 reaches the value of 512 mA cm−2 M−1 with a linear range from 1 μM to 4.5 mM.  相似文献   

9.
In this study, Prussian blue (PB) film on the electroreduced graphene oxide (ERGO)‐modified Au electrode surface (ERGO/PB) is easily prepared by means of cyclic voltammetric technique in the mixture of K3Fe(CN)6 and FeCl3. Its electrochemical behaviors for NADH biosensor are studied. The structural and morphological characters of modified electrode material are analyzed with using of XPS, XRD, Raman, EDS, and SEM techniques. ERGO/PB hybrid nanocomposite for NADH biosensor is exhibited to the higher catalytic effect (linear range from 1.0 to 100 μM, detection limit of 0.23 μM at S/N=3) compared to naked Au, ERGO‐modified Au, and PB‐modified Au electrodes. In addition to, ERGO/PB electrode was used to voltammetric and amperometric detection of H2O2. ERGO/PB electrodes also showed the same behavior as the NADH sensor. This ERGO/PB‐modified electrode supplied a simple, new, and low‐cost route for amperometric sensing of both NADH and H2O2.  相似文献   

10.
A novel hydrogen peroxide (H2O2) sensor was fabricated by using a submonolayer of 3‐mercaptopropionic acid (3‐MPA) adsorbed on a polycrystalline gold electrode further reacted with poly(amidoamine) (PAMAM) dendrimer (generation 4.0) to obtain a film on which Prussian Blue (PB) was later coordinated to afford a mixed and stable electrocatalytic layer for H2O2 reduction. On the basis of the electrochemical behaviors, atomic force microscopy (AFM) and X‐ray photoelectron spectra (XPS), it is suggested that the PB molecules are located within the dendritic structure of the surface attached PAMAM dendrimers. It was found that the PB/PAMAM/3‐MPA/Au modified electrode showed an excellent electrocatalytic activity for H2O2 reduction. The effects of applied potential and pH of solution upon the response of the modified electrode were investigated for an optimum analytical performance. Even in the presence of dissolved oxygen, the sensor exhibited highly sensitive and rapid response to H2O2. The steady‐state cathodic current responses of the modified electrode obtained at ?0.20 V (vs. SCE) in air‐saturated 0.1 mol L?1 phosphate buffer solution (PBS, pH 6.50) showed a linear relationship to H2O2 concentration ranging from 1.2×10?6 mol L?1 to 6.5×10?4 mol L?1 with a detection limit of 3.1×10?7 mol L?1. Performance of the electrode was evaluated with respected to possible interferences such as ascorbic acid and uric acid etc. The selectivity, stability, and reproducibility of the modified electrode were satisfactory.  相似文献   

11.
In this work, the nanosheet‐assembled lindgrenite microflowers (chemical formula: Cu3Mo2O9) were synthesised through a simple process and low‐cost raw materials at room temperature in aqueous solution without using any surface‐active agent. The tightly interlaced nanosheets, like petals, can increase the specific surface area, which can bring about higher electrocatalytic activity and electroanalysis sensitivity. Thus, lindgrenite microflowers were prepared as an electrochemical sensor and successfully applied in the detection of paracetamol through the modified glass carbon electrode. Furthermore, this electrochemical reaction process was simulated at the ab‐initio level to reveal the catalytic mechanism, and the simulation results agreed well with electrochemical experiments. The electrochemical performance of the lindgrenite microflowers modified glassy carbon electrode (GCE) was studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The linearity of paracetamol ranged from 0.05 to 1200 μM (IT method) and 0.05 to 1000 μM (DPV method), low detection limit (0.01 μM) and high sensitivity (5.11 mA mM?1 cm?2) towards paracetamol. Moreover, this sensor was applied to detect paracetamol in human blood serum samples. The excellent results demonstrated that the prepared electrode not only showed a desirable linear range towards paracetamol but also exhibited practical applicability and reliability towards human serum samples detection.  相似文献   

12.
A novel nonenzymatic H2O2 sensor based on a palladium nanoparticles/graphene (Pd‐NPs/GN) hybrid nanostructures composite film modified glassy carbon electrode (GCE) was reported. The composites of graphene (GN) decorated with Pd nanoparticles have been prepared by simultaneously reducing graphite oxide (GO) and K2PdCl4 in one pot. The Pd‐NPs were intended to enlarge the interplanar spacing of graphene nanosheets and were well dispersed on the surface or completely embedded into few‐layer GN, which maintain their high surface area and prevent GN from aggregating. XPS analysis indicated that the surface Pd atoms are negatively charged, favoring the reduction process of H2O2. Moreover, the Pd‐NPs/GN/GCE could remarkably decrease the overpotential and enhance the electron‐transfer rate due to the good contact between Pd‐NPs and GN sheets, and Pd‐NPs have high catalytical effect for H2O2 reduction. Amperometric measurements allow observation of the electrochemical reduction of H2O2 at 0.5 V (vs. Ag/AgCl). The H2O2 reduction current is linear to its concentration in the range from 1×10?9 to 2×10?3 M, and the detection limit was found to be 2×10?10 M (S/N=3). The as‐prepared nonenzymatic H2O2 sensor exhibits excellent repeatability, selectivity and long‐term stability.  相似文献   

13.
A newly nonenzymatic sensor for hydrogen peroxide (H2O2) based on the (Au‐HS/SO3H‐PMO (Et)) nanocomposite is demonstrated. The electrochemical properties of the as‐prepared nanocomposite were studied. It displayed an excellent performance towards H2O2 sensing in the linear response range from 0.20 µM to 4.30 mM (R=0.9999) with a sensitivity of 6.35×102 µA µM?1 cm?2 and a low detection limit of 0.0499 µM. Furthermore, it was not affected by electroactive interference species. These features proved that the modified electrode was suitable for determination of H2O2.  相似文献   

14.
A ternary composite material based on Prussian blue, single‐walled carbon nanotubes and 1‐butyl‐3‐methylimidazolium hexafluorophosphate was prepared and tested for electrochemical detection of H2O2. The sensor allows amperometric detection of H2O2 at ?0.05 V, with a sensitivity of 137 mA M?1?cm?2. The nanocomposite provides a favorable microenvironment for immobilization of horseradish peroxidase (HRP). Determination of xenoestrogenic compounds was performed by enzymatic oxidation at the surface of modified screen printed biosensor in the presence of H2O2. The developed electrochemical biosensors exhibited high sensitivity, low detection limits, good operational and storage stability, for detection of 4‐t‐butylphenol, 4‐t‐octylphenol, 4‐n‐nonylphenol and 4‐n‐nonylphenol ethoxylate.  相似文献   

15.
《Electroanalysis》2006,18(22):2210-2217
A novel method to immobilize hemoglobin (Hb) in a polymer grown from dopamine (DA) oxidation was proposed. The growth of the polymeric films during DA oxidation at the Prussian blue (PB) modified Au electrode in weak alkaline phosphate buffer (pH 9.18) and the immobilization of Hb into the polymeric films during their growth were traced by the electrochemical quartz crystal impedance analysis (EQCIA) method. A hydrogen peroxide (H2O2) biosensor was thus constructed, and effects of experimental parameters on the sensor performance, including the applied potential, solution pH and electroactive interferents, were examined. At an optimal potential of ?0.25 V vs. SCE, the current response of the biosensor in the selected phosphate buffer (pH 5.29) was linear with the concentration of H2O2 from 0.01 to 4.5 mM, with a lower limit of detection of 0.5 μM (S/N=3), short response time (within 10 s) and good anti‐interferent ability. The Michaelis constant (Kmapp) was estimated to be 3.80 mM. Compared with the separate film of PB or Hb, the composite film of Hb and PB exhibited a higher catalytic activity toward the reduction of H2O2, as a result of the additive effect of the chemical and biological catalyses.  相似文献   

16.
There are great challenges to fabricate a highly selective and sensitive enzyme‐free biomimetic sensor. Herein for the first time a unique nanostructure of porous molybdenum carbide impregnated in N‐doped carbon (p‐Mo2C/NC) is synthesized by using SiO2 nanocrystals‐templating method and is further used as an enzyme‐free electrochemical biosensor toward highly selective, sensitive detection of H2O2, of which the limit of detection, dynamic detection range and sensitivity accomplish as 0.22 μM, 0.05–4.5 mM and 577.14 μA mM?1 cm?2, respectively, and are much superior to the non‐porous molybdenum carbide impregnated in N‐doped carbon (Mo2C/NC). The sensor is also used to monitor H2O2 released from A549 living cells. This work holds a great promise to be used to monitor the presence of H2O2 in biological research while offering an important knowledge to design a highly selective and sensitive biomimetic sensor by synthesizing a porous catalyst to greatly improve the reaction surface area rather than conventionally only relying on dispersing the catalyst material into porous carbon substrate.  相似文献   

17.
Prussian blue (PB) modified titanate nanotubes (PB‐TiNT) have been synthesized by the reaction of Fe2+‐modified TiNT with hexacyanoferrate(III) ions. The rate constant for heterogeneous catalytic reaction between PB‐TiNT and H2O2 was found to be k=2×104 dm3 mol?1 s?1, which is an order of magnitude higher than the values of k reported for conventionally prepared, electrochemically deposited PB films. On the PB‐TiNT modified electrode with subnanomolar surface concentration of PB (Γ(PB)=2.8×10?11 mol/cm2), a stable, reproducible and linear response towards H2O2 was obtained in the concentration range 0.02–4 mM, with the sensitivity of 0.10 AM?1 cm?2 at ?150 mV.  相似文献   

18.
We developed a novel iron‐tetrasulfophthalocyanine‐graphene‐Nafion (FeTSPc‐GR‐Nafion) modified screen‐printed electrode to determine hydrogen peroxide (H2O2) with high sensitivity and selectivity. The nanocomposite film (FeTSPc‐GR‐Nafion) exhibits an excellent electrocatalytic activity towards oxidation of H2O2 at a potential of +0.35 V in the absence of enzyme. A comparative study reveals that the FeTSPc‐GR complexes play a dual amplification role. Amperometric experiment indicates that the sensors possess good sensitivity and selectivity, with a linear range from 2.0×10?7 M to 5.0×10?3 M and a detection limit of 8.0×10?8 M. This sensor has been successfully used to develop the glucose biosensor and has also been applied to determine H2O2 in sterile water.  相似文献   

19.
Enzyme-free amperometric ultrasensitive determination of hydrogen peroxide (H2O2) was investigated using a Prussian blue (PB) film-modified gold nanoparticles (AuNPs) graphite–wax composite electrode. A stable PB film was obtained on graphite surface through 2-aminoethanethiol (AET)-capped AuNPs by a simple approach. Field emission scanning electron microscope studies results in formation of PB nanoparticle in the size range of 60–80 nm. Surface modification of PB film on AET–AuNPs–GW composite electrode was confirmed by Fourier transform infrared attenuated total reflection (FTIR-ATR) spectroscopy studies. Highly sensitive determination of H2O2 at a peak potential of ?0.10 V (vs. SCE) in 0.1 M KCl PBS, pH?=?7.0) at a scan rate of 20 mVs?1 with a sensitivity of 23.58 μA/mM was observed with the modified electrode using cyclic voltammetry. The synergetic effect of PB film with AuNPs has resulted in a linear range of 0.05 to 7,800 μM with a detection limit of 0.015 μM for H2O2 detection with the present electrode. Chronoamperometric studies recorded for the successive additions of H2O2 with the modified electrode showed an excellent linearity (R 2?=?0.9932) in the range of 4.8?×?10?8 to 7.4?×?10?8 M with a limit of detection of 1.4?×?10?8 M. Selective determination of H2O2 in presence of various interferents was successfully demonstrated. Human urine samples and stain remover solutions were also investigated for H2O2 content.  相似文献   

20.
The authors describe an electrochemical sensor for hydrogen peroxide (H2O2). It was constructed by consecutive, selective modification of a glassy carbon electrode (GCE) with Prussian Blue (PB), layered molybdenum disulfide (MoS2), and reduced graphene oxide (rGO). The properties of the modified GCE were characterized via high-resolution transmission electron microscopy, UV-vis spectroscopy and X-ray diffraction. The electrochemical properties of the electrode were studied using cyclic voltammetry and electrochemical impedance spectroscopy. The sensor exhibits excellent electrocatalytic activity for the reduction of hydrogen peroxide in comparison to GCEs modified with MoS2-rGO or PB only. Response is linear in the 0.3 μM to 1.15 mM H2O2 concentration range at a working analytical voltage of 0.1 V, with a 0.14 μM detection limit. The electrochemical sensitivity is 2883.5 μA·μM?1·cm?2, and response is fast (<10 s). The sensor is selective, stable and reproducible. This is attributed to the efficient electron transport properties of the MoS2-rGO composite and the high loading with PB.
Graphic abstract Prussian Blue nanoparticles were deposited on MoS2-rGO modified glassy carbon electrode by electrochemical method. This sensor was used for the detection of H2O2 in tap water and river water.
  相似文献   

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