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1.
A novel hydrogen peroxide biosensor has been fabricated based on covalently linked horseradish peroxidase (HRP) onto L- glutathione self-assembled monolayers (SAMs). The SAMs-based electrode was characterized by electrochemical methods, and direct electrochemistry of HRP can be achieved with formal potential of-0.242 V (vs. saturated Ag/AgCl) in pH 7 phosphate buffer solution (PBS), the redox peak current is linear to scan rate and rate constant can be calculated to be 0.042 s^-1. The HRP-SAMs- based biosensors show its better electrocatalysis to hydrogen peroxide in the concentration range of 1 × 10^-6 mol/L to 1.2 × 10^-3 mol/L with a detection limit of 4 × 10^-7 mol/L. The apparent Michealis-Menten constant is 3.12 mmol/L. The biosensor can effectively eliminate the interferences of dopamine, ascorbic acid, uric acid, catechol and p-acetaminophen. 相似文献
2.
Huijun Jiang Chong Du Zhiqing Zou Xiaowei Li Daniel L. Akins Hui Yang 《Journal of Solid State Electrochemistry》2009,13(5):791-798
One-step, diameter-selective dispersion of single-walled carbon nanotubes (SWCNTs) has been accomplished through noncovalent
complexation of the nanotubes with a water-soluble, biocompatible polymer chitosan at room temperature. Such chitosan-wrapped
individual SWCNTs can be used for the immobilization of horseradish peroxidase (HRP) and be used to construct an electrode
for direct bioelectrochemical sensing without an electron mediator. The direct electron transfer between HRP and the electrode
surface was observed with a formal potential of approximately −0.35 V (vs. saturated calomel electrode) in phosphate buffer
solution and the calculated heterogeneous electron transfer rate constant is approximately 23.5 s−1. Experimental results indicate that the immobilized HRP retains its catalytic activity for the reduction of nitric oxide.
Such an HRP–SWCNT–chitosan-based biosensor exhibited a rapid response time of less than 6 s and a good linear detection range
for nitrite concentration, from 25 to 300 μM with a detection limit of 3 μM. The apparent Michaelis–Menten constant (K
m) and the maximum electrode sensitivity (imax/K
m) are found to be 7.0 mM and 0.16 μA mM−1, respectively. Both the unique electrical properties of SWCNTs and biocompatibility of chitosan enable the construction of
an excellent biosensing platform for improved electrocatalysis of HRP, allowing, specifically, the detection of trace levels
of nitric oxide. 相似文献
3.
A hybrid organic-inorganic nanocomposite film of chitosan/sol-gel/multi-walled carbon nanotubes was constructed for the immobilization of horseradish peroxidase (HRP). This film was characterized by scanning electron microscopy. Direct electron transfer (DET) and bioelectrocatalysis of HRP incorporated into the composite film were investigated. The results indicate that the film can provide a favorable microenvironment for HRP to perform DET on the surface of glassy carbon electrodes with a pair of quasi-reversible redox waves and to retain its bioelectrocatalytic activity toward H2O2. 相似文献
4.
A highly soluble poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid)/Au (PEDOT-PSS/Au) nanocomposite was prepared via one-step chemical synthesis and the matrix was characterized by UV-vis spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscope (TEM). Due to the excellent aqueous compatibility and biocompatibility, the PEDOT/PSS-Au nanocomposite can be used as biomaterial for enzymes immobilization. In this system, redox enzyme, horseradish peroxidase (HRP) was integrated with PEDOT/PSS-Au nanocomposite and the direct electron transfer of HRP was observed. Moreover, we find that the HRP/PEDOT-PSS/Au modified electrode shows excellent electrocatalytic ability for H2O2 and the formal Michaelis-Menten constant was 0.78 mmol/L. The response currents have good linear relation with the concentrations of H2O2 with a linear range from 2.0 × 10−7 to 3.8 × 10−4 mol/L. 相似文献
5.
Noya Loew Ulla Wollenberger Frieder W. Scheller Martin Katterle 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,76(1-2):28
In this contribution the substitution of the central protoporphyrin IX iron complex of horseradish peroxidase by the respective osmium porphyrin complex is described. The direct electrochemical reduction of the Os containing horseradish peroxidase (OsHRP) was achieved at ITO and modified glassy carbon electrodes and in combination with spectroscopy revealed the three redox couples OsIIIHRP/OsIVHRP, OsIVHRP/OsVHRP and OsVHRP/OsVIHRP. The midpoint potentials differ dependent on the electrode material used with E1/2 (OsIII/IV) of − 0.4 V (ITO) and − 0.25 V (GC), E1/2 (OsIV/V) of − 0.16 V (ITO) and + 0.10 V (GC), and E1/2 (OsV/VI)of + 0.18 V (ITO), respectively. Moreover, with immobilised OsHRP the direct electrocatalytic reduction of hydrogen peroxide and tert-butyl hydroperoxide was observed. In comparison to electrodes modified with native HRP the sensitivity of the OsHRP-electrode for tert-butyl hydroperoxide is higher. 相似文献
6.
Nengqin Jia Qin Zhou Ling Liu Manming Yan Zhiyu Jiang 《Journal of Electroanalytical Chemistry》2005,580(2):213-221
Horseradish peroxidase (HRP) was immobilized into a new type of sol–gel-derived nano-sized tin oxide/gelatin composite film (SnO2 composite film) using a sol–gel film/enzyme/sol–gel film “sandwich” configuration. Direct electrochemistry and electrocatalysis of HRP incorporated into the composite films were investigated. HRP/SnO2 composite film exhibited a pair of stable and quasi-reversible cyclic voltammetric peaks for the HRP Fe(III)/HRP Fe(II) redox couple with a formal potential of about −0.25 V (vs. SCE) in a pH 6.0 phosphate buffer solution. The electron transfer between the enzyme and the underlying electrode was greatly enhanced in the microenvironment with nano-SnO2 particles and nanoporous structures. Morphologies and microstructures of the composite films and HRP/composite films were characterized with TEM, AFM. Electrochemical impedance spectroscopy (EIS) was also used to feature the HRP incorporated into composite films. FTIR and UV–Vis spectroscopy demonstrated that HRP in the composite film could retain its native secondary structure. With the advantages of organic–inorganic hybrid materials, the HRP/SnO2 composite film modified electrode displayed good stability and electrocatalytic activity to the reduction of H2O2, The apparent Michaelis-Menten constant was estimated to be 0.345 mM, indicating a high affinity of HRP entrapped into the composite film toward H2O2. 相似文献
7.
Zhaoxia Cao Jian Zhang Julan Zeng Lixian Sun Fen Xu Zhong Cao Daowu Yang 《Talanta》2009,77(3):943-9960
In this work, novel mesoporous silica hollow spheres (MSHS) were chosen as an immobilization matrix, to construct a mediator-free third-generation HRP biosensor. UV-vis spectroscopy revealed that horseradish peroxidase (HRP) entrapped in MSHS could retain its native structure. FTIR spectroscopy and nitrogen adsorption-desorption isotherms indicated that HRP are intercalated into the mesopores. The direct electron transfer of HRP entrapped in MSHS was observed. A pair of stable and well-defined redox peaks of HRP with a formal potential of about −0.150 V (vs. Ag/AgCl) in 0.1 M pH 7.0 phosphate-buffered solution (PBS) were obtained. The biosensor exhibited a fast amperometric response to H2O2 with a linear range of 3.9 × 10−6 to 1.4 × 10−4 M (R = 0.997, N = 20). The detection limit was 1.2 × 10−6 M based S/N = 3. 相似文献
8.
A new kind of magnetic dextran microsphere (MDMS) with uniform shape and narrow diameter distribution has been prepared from
magnetic iron nanoparticles and dextran. Horseradish peroxidase (HRP) was successfully immobilized on the surface of an MDMS-modified
glassy-carbon electrode (GCE), and the immobilized HRP displayed excellent electrocatalytic activity in the reduction of H2O2 in the presence of the mediator hydroquinone (HQ). The effects of experimental variables such as the concentration of HQ,
solution pH, and the working potential were investigated for optimum analytical performance. This biosensor had a fast response
to H2O2 of less than 10 s and an excellent linear relationship was obtained in the concentration range 0.20 μmol L−1–0.68 mmol L−1, with a detection limit of 0.078 μmol L−1 (S/N = 3) under the optimum conditions. The response showed Michaelis–Menten behavior at larger H2O2 concentrations, and the apparent Michaelis–Menten constant was estimated to be 1.38 mmol L−1. Moreover, the selectivity, stability, and reproducibility of the biosensor were evaluated, with satisfactory results.
Figure Amperometric response of the biosensor to successive additions of H2O2 and the plot of amperometric response vs. H2O2 concentration 相似文献
9.
Yuehua Dou Stephen Haswell John Greenman Jay Wadhawan 《Electrochemistry communications》2009,11(10):1976-1981
The detection of hydrogen peroxide is detailed using horseradish peroxidase and anthraquinone. Both species are immobilized on a glassy carbon electrode substrate. This dual immobilization gives rise to lower detection limits compared with the situation when either of the species is immobilized. Detection limits of 40 nM are reported within physiologically-relevant media. 相似文献
10.
In this paper, a simple two-step approach for redox protein immobilization was introduced. Firstly, alkynyl-terminated film was formed on electrode surface by electrochemical reduction of 4-ethylnylphenyl (4-EP) diazonium compound. Then, horseradish peroxidase (HRP) modified with azido group was covalently immobilized onto the electrografted film via click reaction. Reflection absorption infrared (RAIR) spectroscopy and electrochemical methods were used to characterize the modification process. The results indicate that HRP retains its native structure and shows fast direct electron transfer. Moreover, the immobilized HRP shows excellent electrocatalytic reduction activity toward H(2)O(2) with a linear range of 5.0×10(-6) to 9.3×10(-4) mol L(-1). 相似文献
11.
The heme-protein including myoglobin (Mb), hemoglobin (Hb) and horseradish peroxidase (HRP) were immobilized on normal graphite electrode by using N,N-dimethylformamide (DMF). The proteins undergo direct electron-transfer reactions. The current is linearly dependent on the scan rate, indicating that the direct electrochemistry of heme-protein in that case is a surface-controlled electrode process. The E°s are linearly dependent on solution pH (redox-Bohr effect), indicating that the electron transfer was proton-coupled. Ultraviolet-visible (UV-vis) and reflection-absorption infrared (RAIR) spectra suggest that the conformation of proteins in the presence of DMF are little different from that proteins alone the conformation changes reversibly in the range of pH 3.0-10.0. The catalytic activity of proteins were examined by hydrogen peroxide and nitrite. 相似文献
12.
A simple and reliable one-pot approach was established for the development of a novel hydrogen peroxide (H2O2) biosensor based on in situ covalent immobilization of horseradish peroxidase (HRP) into biocompatible material through polysaccharide-incorporated sol-gel process. Siloxane with epoxide ring and trimethoxy anchor groups was applied as the bifunctional cross-linker and the inorganic resource for organic-inorganic hybridization. The reactivity between amine groups and epoxy groups allowed the covalent incorporation of HRP and the functional biopolymer, chitosan (CS) into the inorganic polysiloxane network. Some experimental variables, such as mass ratio of siloxane to CS, pH of measuring solution and applied potential for detection were optimized. HRP covalently immobilized in the hybrid matrix possessed high electrocatalytic activity to H2O2 and provided a fast amperometric response. The linear response of the as-prepared biosensor for the determination of H2O2 ranged from 2.0 × 10−7 to 4.6 × 10−5 mol l−1 with a detection limit of 8.1 × 10−8 mol l−1. The apparent Michaelis-Menten constant was determined to be 45.18 μmol l−1. Performance of the biosensor was also evaluated with respect to possible interferences. The fabricated biosensor exhibited high reproducibility and storage stability. The ease of the one-pot covalent immobilization and the biocompatible hybrid matrix serve as a versatile platform for enzyme immobilization and biosensor fabricating. 相似文献
13.
Xiaohong Chen Xuesong Peng Jilie Kong Jiaqi Deng 《Journal of Electroanalytical Chemistry》2000,480(1-2)
Direct electron transfer was found to be greatly facilitated for horseradish peroxidase (HRP) in a didodecyldimethylammonium bromide (DDAB) biomembrane-like film at a pyrolytic graphite (PG) electrode involving the FeIII FeII couple. The heterogeneous electron transfer rate constant ks was fitted as 9.0 s−1 using the non-linear regression analysis of the square wave voltammograms at a series of frequencies and pulse heights. The pH dependence of the formal potential for HRP in DDAB film at medium pH environments suggested one-proton transfer coupled with a one-electron transfer reaction. Scanning electron microscopy (SEM) showed different film morphology for HRP and HRP---DDAB films. UV–vis and reflectance absorption infrared (RAIR) spectra inferred that the heme state of HRP in DDAB film was similar to that in its native state. Circular dichroism (CD) results indicated slight perturbation of DDAB on the second structure of HRP. Thus, the embedded HRP in the biomembrane-like DDAB film showed nearly native structural properties and improved electrochemical characteristics. This has potential value for the basic and applied bioelectrochemistry of enzymes. 相似文献
14.
A sandwich-type electrochemical immunosensor for the detection of carbohydrate antigen 19-9 (CA 19-9) antigen based on the immobilization of primary antibody (Ab1) on three dimensional ordered macroporous magnetic (3DOMM) electrode, and the direct electrochemistry of horseradish peroxidase (HRP) that was used as both the label of secondary antibody (Ab2) and the blocking reagent. The 3DOMM electrode was fabricated by introducing core–shell Au–SiO2@Fe3O4 nanospheres onto the surface of three dimensional ordered macroporous (3DOM) Au electrode via the application of an external magnet. Au nanoparticles functionalized SBA-15 (Au@SBA-15) was conjugated to the HRP labeled secondary antibody (HRP-Ab2) through the Au–SH or Au–NH3+ interaction, and HRP was also used as the block reagent. The formation of antigen–antibody complex made the combination of Au@SBA-15 and 3DOMM exhibit remarkable synergistic effects for accelerating direct electron transfer (DET) between HRP and the electrode. Under the optimal conditions, the DET current signal increased proportionally to CA 19-9 concentration in the range of 0.05 to 15.65 U mL−1 with a detection limit of 0.01 U mL−1. Moreover, the immunosensor showed high selectivity, good stability, satisfactory reproducibility and regeneration. Importantly, the developed method was used to assay clinical serum specimens, achieving a good relation with those obtained from the commercialized electrochemiluminescent method. 相似文献
15.
Hydrogen peroxide sensor based on horseradish peroxidase immobilized on a silver nanoparticles/cysteamine/gold electrode 总被引:1,自引:0,他引:1
A third-generation hydrogen peroxide biosensor was prepared by immobilizing horseradish peroxidase (HRP) on a gold electrode modified with silver nanoparticles. A freshly-cleaned gold electrode was first immersed in a cysteamine–ethanol solution, and then silver nanoparticles were immobilized on the cysteamine monolayer, and finally HRP was adsorbed onto the surfaces of the silver nanoparticles. This self-assemble process was examined via atomic force microscopy (AFM). The immobilized horseradish peroxidase exhibited an excellent electrocatalytic response toward the reduction of hydrogen peroxide. The linear range of the biosensor was 3.3 M to 9.4 mM, and the detection limit was estimated to be 0.78 M. Moreover, the biosensor exhibited a fast response, high sensitivity, good reproducibility, and long-term stability. 相似文献
16.
A novel, simple and versatile protocol for covalent immobilization of horseradish peroxidase (HRP) on screen‐printed carbon electrode (SPCE) based on the combination of diazonium salt electrografting and click chemistry has been successfully developed. The ethynyl‐terminated monolayers are obtained by diazonium salt electrografting, then, in the presence of copper (I) catalyst, the ethynyl modified surfaces reacted efficiently and rapidly with horseradish peroxidase bearing an azide function (azido‐HRP), thus forming a covalent 1,2,3‐triazole linkage by means of click chemistry. All the experimental results suggested that HRP was immobilized onto the electrode surface successfully without denaturation. Furthermore, the immobilized HRP showed a fast electrocatalytic reduction for H2O2. A linear range from 5.0 to 50.0 µM in a phosphate buffer (pH 5.5) with detection limit of 0.50 µM and sensitivity of 0.23 nA/µM were obtained. The heterogeneous electron transfer rate constant Kct was 1.52±0.22 s?1 and the apparent Michaelis? Menten constant was calculated to be 0.028 mM. The HRP‐functionalized electrode demonstrated a good reproducibility and long‐term stability. 相似文献
17.
An amperometric biosensor, based on layer-by-layer self-assembly of colloidal gold nanoparticles, cysteine and horseradish
peroxidase on Nafion modified electrode surface by electrostatic adsorption, has been used for the determination of hydrogen
peroxide. The electrochemical behavior of the multilayer film was studied by cyclic voltammetry, linear sweep voltammetry
and chronoamperometry. The step layer-by-layer adsorption interface morphology was further characterized by means of electrochemical
impedance spectroscopy and cyclic voltammetry. The performance and factors influencing the resulted biosensor were studied
in detail. The sensor displayed an excellent electrocatalytic response to the reduction of H2O2 without the aid of an electron transfer mediator. Linear response to H2O2 was obtained for the concentration range from 1.6 μM to 2.4 mM under optimized conditions. The detection limit of the biosensor
was 0.5 μM (S/N = 3), and the sensor achieved 95% of the steady-state current within 10 s. The sensor exhibited high sensitivity,
selectivity and stability.
Correspondence: Yan Liu, College of Chemistry, Chongqing Normal University, Chongqing 400047, P.R. China 相似文献
18.
Yuan R Liu Y Li QF Chai YQ Mo CL Zhong X Tang DP Dai JY 《Analytical and bioanalytical chemistry》2005,381(3):762-768
A new hydrogen peroxide biosensor was constructed, which consisted of a platinum electrode modified by a matrix of polyvinyl butyral (PVB) and nanometer-sized Ag colloid containing immobilized horseradish peroxidase (HRP), and using Co(bpy)33+ as mediator in the hydrogen peroxide solution. The electrochemical characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. The modified process was characterized by electrochemical impedance spectroscopy and cyclic voltammetry. The HRP immobilized on colloidal Ag was stable and retained its biological activity. The sensor displays excellent electrocatalytic response to the reduction of H2O2. Analytical parameters such as pH and temperature were also studied. Linear calibration for H2O2 was obtained in the range of 1×10–5 to 1×10–2 M under optimized conditions. The sensor was highly sensitive to H2O2, with a detection limit of 2×10–6 M, and the sensor achieved 95% of steady-state current within 10 s. The sensor exhibited high sensitivity, selectivity and stability. 相似文献
19.
Guo C Song Y Wei H Li P Wang L Sun L Sun Y Li Z 《Analytical and bioanalytical chemistry》2007,389(2):527-532
A novel electrochemical H2O2 biosensor was constructed by embedding horseradish peroxide (HRP) in a 1-butyl-3-methylimidazolium tetrafluoroborate doped
DNA network casting on a gold electrode. The HRP entrapped in the composite system displayed good electrocatalytic response
to the reduction of H2O2. The composite system could provide both a biocompatible microenvironment for enzymes to keep their good bioactivity and
an effective pathway of electron transfer between the redox center of enzymes, H2O2 and the electrode surface. Voltammetric and time-based amperometric techniques were applied to characterize the properties
of the biosensor. The effects of pH and potential on the amperometric response to H2O2 were studied. The biosensor can achieve 95% of the steady-state current within 2 s response to H2O2. The detection limit of the biosensor was 3.5 μM, and linear range was from 0.01 to 7.4 mM. Moreover, the biosensor exhibited
good sensitivity and stability. The film can also be readily used as an immobilization matrix to entrap other enzymes to prepare
other similar biosensors.
Figure Horseradish peroxidase (HRP) embedded in a 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM·BF
4
) doped DNA network can be used to fabricate a HRP sensor for the determination of H2O2 相似文献
20.
辣根过氧化酶(HRP)在Co/NH2/ITO离子注入电极上有一对良好的氧化还原峰,峰电位分别为Epc=-0.2 V,Epa=-0.01 V(vsAg/AgCl)。该修饰电极对H2O2具有催化作用,可以用作H2O2的生物传感器,峰电流与H2O2的浓度分别在1.0×10-10~2.0×10-8mol/L和2.0×10-8~1.0×10-7mol/L范围内呈线性关系,线性回归方程分别为Ip(mA)=2.2986+0.06632c(nmol/L)和Ip(mA)=3.5788+7.3053E-4c(nmol/L),相关系数分别为0.9972和0.9688。检出限为1.0×10-10mol/L。 相似文献