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Qingsong Yang Li Li Liang Sun Zhishuang Ye Yunwei Wang Xuhong Guo 《Journal of polymer science. Part A, Polymer chemistry》2021,59(19):2201-2211
The integration of nanozyme and natural enzyme for cascade reactions has attracted great attention due to their huge potential applications in detection, biomedicine, and catalysis. Here the novel cascade bio-platforms were fabricated by using spherical poly[(2-methacryloyloxyethyl)trimethyl ammonium chloride] (PMOTA) brushes (SPB) as nanoreactors to prepare platinum nanoparticles in situ and as nanocarriers to immobilize glucose oxidase (GOX). The generated Pt nanoparticles possess high stability and peroxidase-like properties, which can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2 to generate blue colored oxidized TMB (oxTMB). And the absorbed GOX can specifically catalyze the oxidation of glucose into gluconic acid and H2O2, while the produced H2O2 is subsequently catalyzed by the Pt nanozymes. Thus, the co-immobilized Pt nanozymes and GOX within SPB (SPB@Pt@GOX) acted as effective biosensors for colorimetric detection of glucose showing high selectivity and great feasibility. This work demonstrates a facile and general strategy to use SPB as bio-platforms to integrate nanozymes and natural enzymes for cascade reactions. 相似文献
3.
U. Wollenberger F. Scheller D. Pfeiffer V.A. Bogdanovskaya M.R. Tarasevich G. Hanke 《Analytica chimica acta》1986
The electrode involves a layer of co-immobilized glucose oxidase and laccase in a gelatin membrane placed over a modified oxygen electrode. Hexacyanoferrate(III) is added to the samples to oxidize reductive interferents such as ascorbic acid, and the hexacyanoferrate(II) formed is re-oxidized by a laccase-catalyzed reaction. Ascorbic acid is completely eliminated up to a concentration of 20 mM in the sample. 相似文献
4.
A. Paula V. Goncalves M. BÁrbara F. Martins M. EugÉnia M. Cruz 《Applied biochemistry and biotechnology》1991,27(2):139-143
With the aim of immobilizing glucose oxidase (GO) for routine determination of glucose, a covalent bond immobilization method on titanium (IV) chloride activated silica supports was used (1). Several parameters were studied in order to optimize the residual activity upon immobilization and during operation. The immobilized enzyme can be reutilized at 25°C for several h a day alternating with storage (4°C) for at least 3,300 h. 相似文献
5.
A flow enthalpimetric method for the determination of glucose is presented. The method is based on the reaction of glucose with 1,4-benzoquinone in the presence of immobilized glucose oxidase. d-Glucose concentrations ranging from 0.02 to 75mM can be determined. The method is applicable to the determination of glucose in soft drinks, wines, beers, jams and serum. 相似文献
6.
Su-Juan Li Ti-Wei Chen Ning Xia Ya-Li Hou Jing-Jing Du Lin Liu 《Journal of Solid State Electrochemistry》2013,17(9):2487-2494
Sulfonated graphene nanosheet/gold nanoparticle (SGN/Au) hybrid was synthesized by electrostatic self-assembly of anionic SGN and positively charged gold nanoparticles. Due to the well-dispersivity of SGN in aqueous solution and its adequate negative charge, Au nanoparticles were assembled uniformly on graphene surface with high distribution. With the advantages of both graphene and Au nanoparticles, SGN/Au hybrid showed enhanced electrocatalytic activity towards O2 reduction. Furthermore, it provided a conductive and favorable microenvironment for the glucose oxidase (GOD) immobilization and thus promoted its direct electron transfer at the glassy carbon electrode. Based on the consumption of O2 caused by glucose at the interface of GOD electrode modified with SGN/Au hybrid, the modified electrode displayed satisfactory analytical performance, including high sensitivity (14.55 μA mM?1 cm?2), low detection limit (0.2 mM), an acceptable linear range from 2 to 16 mM, and also the prevention from the interference of some species. These results indicated that the prepared SGN/Au hybrid is a promising candidate material for high-performance glucose biosensor. 相似文献
7.
Colloid Au (Au(nano)) with a diameter of about 10 nm was prepared and used in combination with dihexadecylphosphate (DHP) to immobilize glucose oxidase (GOD) onto the surface of a graphite electrode (GE). The direct electrochemistry of GOD confined in the composite film was investigated. The immobilized GOD displayed a pair of redox peaks with a formal potential of -0.475 mV in pH 7.0 O(2)-free phosphate buffers at scan rate of 150 mV s(-1). The GOD in the composite film retained its bioactivity and could catalyze the reduction of dissolved oxygen. Upon the addition of glucose, the reduction peak current of dissolved oxygen decreased, which could be developed for glucose determination. A calibration linear range of glucose was 0.5-9.3 mM with a detection limit of 0.1 mM and a sensitivity of 1.14 microA mM(-1). The glucose biosensor showed good reproducibility and stability. The general interferences that coexisted in human serum sample such as ascorbic acid and uric acid did not affect glucose determination. 相似文献
8.
A novel glucose biosensor, based on the modification of well-aligned polypyrrole nanowires array (PPyNWA) with Pt nanoparticles (PtNPs) and subsequent surface adsorption of glucose oxidase (GOx), is described. The distinct differences in the electrochemical properties of PPyNWA–GOx, PPyNWA–PtNPs, and PPyNWA–PtNPs–GOx electrodes were revealed by cyclic voltammetry. In particular, the results obtained for PPyNWA–PtNPs–GOx biosensor showed evidence of direct electron transfer due mainly to modification with PtNPs. Optimum fabrication of the PPyNWA–PtNPs–GOx biosensor for both potentiometric and amperometric detection of glucose were achieved with 0.2 M pyrrole, applied current density of 0.1 mA cm−2, polymerization time of 600 s, cyclic deposition of PtNPs from −200 mV to 200 mV, scan rate of 50 mV s−1, and 20 cycles. A sensitivity of 40.5 mV/decade and a linear range of 10 μM to 1000 μM (R2 = 0.9936) were achieved for potentiometric detection, while for amperometric detection a sensitivity of 34.7 μA cm−2 mM−1 at an applied potential of 700 mV and a linear range of 0.1–9 mM (R2 = 0.9977) were achieved. In terms of achievable detection limit, potentiometric detection achieved 5.6 μM of glucose, while amperometric detection achieved 27.7 μM. 相似文献
9.
A planar platinum electrode was covered by a photopolymer membrane containing glucose oxidase (GOD) to construct an amperometric
glucose sensor. The application of a photopolymer system in membrane formation gives the opportunity to manufacture cheap
biosensors with good reproducibility by means of automated techniques and to miniaturise sensors using photolithography. The
electrodes were pretreated mechanically and chemically resulting in a half-wave potential (E1/2) of the H2O2 oxidation shifted towards more negative potentials. This shift allows the determination of glucose at a low working potential
(300 mV vs. SCE) without addition of mediators. The important advantage of such applied potential decreasing lies in minimising
the interference of oxidisable substances such as uric acid, bilirubin and paracetamol. The selectivity to ascorbic acid could
also be proved without the application of additional protection layers. The glucose sensor developed has a high life-time,
selectivity and sensitivity and a linear working concentration range from 0.05 up to 10 mmol/l of glucose. The sensor was
used for the glucose determination in human serum samples with a very good correlation to a common photometric reference method.
Received: 13 July 1996 / Revised: 11 September 1996 / Accepted: 14 September 1996 相似文献
10.
Jingjing Yu Jiaxing Tu Faqiong Zhao Baizhao Zeng 《Journal of Solid State Electrochemistry》2010,14(9):1595-1600
A magnetic mesoporous carbon material (i.e., mesoporous iron oxide/C, mesoFe/C) is synthesized for protein immobilization,
using glucose oxidase (GOx) as model. Transmission electron microscopy images show that mesoFe/C has highly ordered porous
structure with uniform pore size, and iron oxide nanoparticles are dispersed along the wall of carbon. After adsorption of
GOx, the GOx-mesoFe/C composite is separated with magnet. The immobilized GOx remains its natural structure according to the
reflection–absorption infrared spectra. When the GOx-mesoFe/C composite is coated on a Pt electrode surface, the GOx gives
a couple of quasireversible voltammetric peaks at −0.5 V (vs. saturated calomel electrode) due to the redox of FAD/FADH2. The electron-transfer rate constant (k
s) is ca. 0.49 s−1. The modified electrode presents remarkably amperometric response to glucose at 0.6 V. The response time (t
95%) is less than 6 s; the response current is linear to glucose concentration in the range of 0.2–10 mM with a sensitivity of
27 μA mM−1 cm−2. The detection limit is 0.08 mM (S/N = 3). The apparent Michaelis–Menten constant (K
mapp) of the enzyme reaction is ca. 6.6 mM, indicating that the GOx immobilized with mesoFe/C has high affinity to the substrate. 相似文献
11.
Biosensors for determination of glucose with glucose oxidase immobilized on an eggshell membrane 总被引:1,自引:0,他引:1
A glucose biosensor using an enzyme-immobilized eggshell membrane and oxygen electrode for glucose determination has been fabricated. Glucose oxidase was covalently immobilized on an eggshell membrane with glutaraldehyde as a cross-linking agent. The glucose biosensor was fabricated by positioning the enzyme-immobilized eggshell membrane on the surface of a dissolved oxygen sensor. The detection scheme was based on the depletion of dissolved oxygen content upon exposure to glucose solution and the decrease in the oxygen level was monitored and related to the glucose concentration. The effect of glutaraldehyde concentration, pH, phosphate buffer concentration and temperature on the response of the glucose biosensor has been studied in detail. Common matrix interferents such as ethanol, d-fructose, citric acid, sodium benzoate, sucrose and l-ascorbic acid did not give significant interference. The resulting sensor exhibited a fast response (100 s), high sensitivity (8.3409 mg L−1 oxygen depletion/mmol L−1 glucose) and good storage stability (85.2% of its initial sensitivity after 4 months). The linear response is 1.0×10−5 to 1.3×10−3 mol L−1 glucose. The glucose content in real samples such as commercial glucose injection preparations and wines was determined, and the results were comparable to the values obtained from a commercial glucose assay kit based on a spectrophotometric method. 相似文献
12.
Enzyme electrodes were constructed by immobilization of glucose oxidase and ferrocene into cross-linked polyacrylamide gels. Electrogenerated ferrocinium ion acts as a direct electron mediator between glucose oxidase and a reticulated vitreous carbon (RVC)/graphite support bed. The electrode is easily constructed, gives a current response proportional to glucose concentrations up to 30 mM, and has good chemical stability in water and air. 相似文献
13.
CAI Chenxin CHEN Jing & LU Tianhong Department of Chemistry Nanjing Normal University Nanjing China 《中国科学B辑(英文版)》2004,47(2):113-119
The direct electrochemistry of redox enzymes (or proteins) has received more and more attention[1—9]. These studies developed an electrochemical basis for the investigation of enzyme structure, mechanisms of redox transformations of enzyme molecules and metabolic processes involving redox transformations. From these studies, one can also find potential appli-cations of enzymes in biotechnology. For example, if an enzyme immobilized on electrode surface is ca-pable of the direct electron tra… 相似文献
14.
A thermal flow system for glucose determination is described, that utilizes a column of glucose oxidase immobilized on a cation-exchange resin (Amberlite CG50). The response is linear for glucose concentrations in the range 0.01-0.4mM. Stability and the factors influencing the response have been examined. 相似文献
15.
ATP determination is of great importance since this compound is involved in a number of vital biological processes. To monitor ATP concentration levels, we have developed a microbiosensor based on cylindrical platinum microelectrode, covered with a layer of poly-m-phenylendiamine (PPD), and layer of co-immobilised glucose oxidase and hexokinase. Conditions for biosensor measurement of ATP (pH, Mg2+ and substrates concentration) in vitro and microbiosensor characteristics such as sensitivity, selectivity, reproducibility, storage stability were studied and optimized. Under optimal conditions the microbiosensor can measure ATP concentrations down to a 2.5 μM detection limit with response time about 15 s. Interferences by electroactive compounds like biogenic amines and their metabolites, ascorbic acid, uric acid and l-cystein are rejected in general by the PPD layer. The microbiosensor developed is insensitive to ATP analogues (or substances with similar structure), such as ADP, AMP, GTP and UTP, too. It can be used for ATP analysis in vitro in the reactions consuming or producing macroergic triphosphate molecules to study kinetics of the process and in drug design concerning development of inhibitors specific to target kinases and others target enzymes. 相似文献
16.
Sulfite oxidase is immobilized on collagen membrane at the surface of a platinum electrode and catalyzes the oxidation of sulfite to sulfate with stoichiometric production of hydrogen peroxide. The hydrogen peroxide is detected amperometically at the platinum electrode at an applied potential of 700 mV. The system responds linearly to sulfite in the range 1–150 μM, with a detection limit of 0.2 μM. The enzyme retains over 95% of its activity for three weeks if stored at ?20° C when the probe is not in use. 相似文献
17.
A feasible method to fabricate glucose biosensor was developed by covalent attachment of glucose oxidase (GOx) to a gold nanoparticle monolayer modified Au electrode. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) of ferrocyanide followed and confirmed the assemble process of biosensor, and indicated that the gold nanoparticles in the biosensing interface efficiently improved the electron transfer between analyte and electrode surface. CV performed in the presence of excess glucose and artificial redox mediator, ferrocenemethanol, allowed to quantify the surface concentration of electrically wired enzyme (Gamma(E)(0)) on the basis of kinetic models reported in literature. The Gamma(E)(0) on proposed electrode was high to 4.1 x 10(-12) mol.cm(-2), which was more than four times of that on electrode direct immobilization of enzyme by cystamine without intermediate layer of gold nanoparticles and 2.4 times of a saturated monolayer of GOx on electrode surface. The analytical performance of this biosensor was investigated by amperometry. The sensor provided a linear response to glucose over the concentration range of 2.0 x 10(-5)-5.7 x 10(-3) M with a sensitivity of 8.8 microA.mM(-1).cm(-2) and a detection limit of 8.2 microM. The apparent Michaelis-Menten constant (K(m)(app)) for the sensor was found to be 4.3 mM. In addition, the sensor has good reproducibility, and can remain stable over 30 days. 相似文献
18.
A stable glucose biosensor prepared by co-immobilizing glucose oxidase into poly(p-chlorophenol) at a platinum electrode 总被引:2,自引:0,他引:2
Xu JJ Zhang XQ Yu ZH Fang HQ Chen HY 《Fresenius' Journal of Analytical Chemistry》2001,369(6):486-490
An amperometric glucose biosensor was successfully developed by electrochemical polymerization of p-chlorophenol (4-CP) at a Pt electrode in the presence of glucose oxidase. The amperometric response of this biosensor to hydrogen peroxide, formed as the product of enzymatic reaction, was measured at a potential of 0.6 V (vs. SCE) in phosphate buffer solution. The performances of sensors, prepared at different monomer concentrations and polymerization potentials, were investigated in detail. The biosensor prepared under optimal conditions had a linear response to glucose ranging from 2.5 x 10(-4) to 1.5 x 10(-2) mol L(-1) with a correlation coefficient of 0.997 and a response time of less than 2 s. Substrate selectivity of the polymer-based enzyme electrode was tested for coexisting interferents such as uric acid and ascorbic acid, and no discernible response was observed. After 90 days, the response of the biosensor remained almost unchanged, indicating very good stability. 相似文献
19.
Jing-Juan Xu Xiao-Qiang Zhang Zhi-Hao Yu Hui-Qun Fang Hong-Yuan Chen 《Analytical and bioanalytical chemistry》2001,369(6):486-490
An amperometric glucose biosensor was successfully developed by electrochemical polymerization of p-chlorophenol (4-CP) at a Pt electrode in the presence of glucose oxidase. The amperometric response of this biosensor to hydrogen peroxide, formed as the product of enzymatic reaction, was measured at a potential of 0.6 V (vs. SCE) in phosphate buffer solution. The performances of sensors, prepared at different monomer concentrations and polymerization potentials, were investigated in detail. The biosensor prepared under optimal conditions had a linear response to glucose ranging from 2.5 × 10–4 to 1.5 × 10–2 mol L–1 with a correlation coefficient of 0.997 and a response time of less than 2 s. Substrate selectivity of the polymer-based enzyme electrode was tested for coexisting interferents such as uric acid and ascorbic acid, and no discernible response was observed. After 90 days, the response of the biosensor remained almost unchanged, indicating very good stability. 相似文献
20.
Xiaodong Shangguan Hongfang Zhang Jianbin Zheng 《Electrochemistry communications》2008,10(8):1140-1143
Direct electrochemistry of glucose oxidase (GOx) has been achieved by its direct immobilization on carbon ionic liquid electrode (CILE) with a conductive hydrophobic ionic liquid, 1-butyl pyridinium hexafluophosphate ([BuPy][PF6]) as binder for the first time. A pair of reversible peaks is exhibited on GOx/CILE by cyclic voltammetry. The peak-to-peak potential separation (ΔEP) of immobilized GOx is 0.056 V in 0.067 M phosphate buffer solution (pH 6.98) with scan rate of 0.1 V/s. The average surface coverage and the apparent Michaelis–Menten constant are 6.69 × 10−11 mol·cm−2 and 2.47 μM. GOx/CILE shows excellent electrocatalytic activity towards glucose determination in the range of 0.1–800 μM with detection limit of 0.03 μM (S/N = 3). The biosensor has been successfully applied to the determination of glucose in human plasma with the average recoveries between 95.0% and 102.5% for three times determination. The direct electrochemistry of GOx on CILE is achieved without the help of any supporting film or any electron mediator. GOx/CILE is inexpensive, stable, repeatable and easy to be fabricated. 相似文献