共查询到20条相似文献,搜索用时 15 毫秒
1.
E.A. DontsovaAuthor VitaeY.S. ZeifmanAuthor Vitae I.A. BudashovAuthor VitaeA.V. EremenkoAuthor Vitae S.L. KalnovAuthor VitaeI.N. KurochkinAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):261-270
This paper presents the amperometric biosensor that determines choline and cholinesterase activity using a screen printed graphite electrode. In order to detect H2O2 we have blanket modified the electrode material with manganese dioxide nanoparticles layer. Using layer-by-layer technique on the developed hydrogen peroxide sensitive electrode surface choline oxidase was incorporated into the interpolyelectrolyte nanofilm. Its ability to serve as a detector of choline in bulk analysis and cholinesterase assay was investigated. We examined the interferences from red-ox species and heavy metals in the blood and in the environmental sample matrixes. The sensor exhibited a linear increase of the amperometric signal at the concentration of choline ranging from 1.3 × 10−7 to 1.0 × 10−4 M, with a detection limit (evaluated as 3σ) of 130 nM and a sensitivity of 103 mA M−1 cm−2 under optimized potential applied (480 mV vs. Ag/AgCl). The biosensor retained its activity for more than 10 consecutive measurements and kept 75% of initial activity for three weeks of storage at 4 °C. The R.S.D. was determined as 1.9% for a choline concentration of 10−4 M (n = 10) with a typical response time of about 10 s. The developed choline biosensor was applied for butyrylcholinesterase assay showing a detection limit of 5 pM (3σ). We used the biosensor to develop the cholinesterase inhibitor assay. Detection limit for chlorpyrifos was estimated as 50 pM. 相似文献
2.
Li-Jun FengAuthor VitaeXiu-Hua ZhangAuthor Vitae Dong-Ming ZhaoAuthor VitaeSheng-Fu WangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,152(1):88-93
A biosensor based on bovine serum albumin (BSA) and poly-o-phenylenediamine (PoPD)/carbon-coated nickel (C-Ni) nanobiocomposite film modified electrode has been developed to study the interaction of BSA with papaverine (PAP). The well-dispersed C-Ni nanoparticles were dripped onto the glassy carbon electrode (GCE) surface firstly, and PoPD films were subsequently electropolymerized by cyclic voltammetry (CV) to prepare PoPD/C-Ni/GCE. Finally, the BSA was easily immobilized on the PoPD films via electrostatic adsorption. The morphology and the electrochemical properties of the fabricated composite electrodes were examined by scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS), respectively. The interaction of PAP with BSA was monitored by differential pulse voltammetry (DPV), using PoPD as the electrochemical indicator. The binding constant (K), obtained by DPV, was 1.7 × 104 L/mol, which was consistent with the fluorescence analysis. This constructed biosensor also exhibited a fine linear correlation with PAP concentration range of 2.5 × 10−9-4.5 × 10−5 mol/L and a detection limit of 8.3 × 10−10 mol/L was achieved by DPV. 相似文献
3.
Qingxiang WangAuthor Vitae Bin ZhangAuthor VitaeXiaoqiang LinAuthor Vitae Wen WengAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):599-605
A label-free DNA biosensor for hybridization detection of short DNA species related to the transgenic plants gene fragment of cauliflower mosaic virus (CaMV) 35S promoter was developed in this paper. The nanocomposite containing chitosan (CS) and mutiwalled carbon nanotubes (MWNTs) was first coated on a glassy carbon electrode. Then a highly reactive dialdehyde reagent of glutaraldehyde (GTD) was applied as an arm linker to covalently graft the 5′-amino modified probe DNA to the CS-MWNTs surface via the facile aldehyde-ammonia condensation reaction. The hybridization capacity of the developed biosensor was monitored with electrochemical impedance spectroscopy (EIS) using [Fe(CN)6]3−/4− as an indicating probe, and the experimental results showed that the biosensor had fast hybridization rate and low background interference. A wide dynamic detection range (1.0 × 10−13-5 × 10−10 M) and a low detection limit (8.5 × 10−14 M) were achieved for the complementary sequence. In addition, the hybridization specificity experiments showed that the sensing system can accurately discriminate complementary sequence from mismatch and noncomplementary sequences. 相似文献
4.
Ming LiuAuthor Vitae Yangping WenAuthor Vitae Dong LiAuthor Vitae Ruirui YueAuthor VitaeJingkun XuAuthor Vitae Haohua HeAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):277-285
In this paper, a stable sandwich-type amperometric biosensor based on poly(3,4-ethylenedioxythiophene) (PEDOT)-single walled carbon nanotubes (SWCNT)/ascorbate oxidase (AO)/Nafion films for detection of l-ascorbic acid (AA) was successfully developed. PEDOT-SWCNT nanocomposite and Nafion films were used as inner and outer films, respectively. AO was immobilized between these two films. The PEDOT-SWCNT nanocomposite films were characterized by electrochemical impedance spectroscopy and scanning electron microscopy. The influence of detection potential and temperature on the biosensor performance was examined in detail. Despite the multilayer configuration, the biosensor exhibited a relatively fast response (less than 10 s) and a linear range from 1 μM to 18 mM (a correlation coefficient of 0.9974). The sensitivity of the biosensor was found to be 28.5 mA M−1 cm−2. Its experimental detection limit was 0.7 μM (S/N = 3) and the apparent Michaelis-Menten constant (Km) was calculated to be 18.35 mM. Moreover, the biosensor exhibited good anti-interferent ability and excellent long-term stability. All the results showed that such sandwich-type PEDOT-SWCNT/AO/Nafion films could provide a promising platform for the biosensor designs for AA detection. 相似文献
5.
Jing LiAuthor VitaeHuaqing XieAuthor Vitae Lifei ChenAuthor Vitae 《Sensors and actuators. B, Chemical》2011,153(1):239-245
A highly sensitive hydrazine sensor was developed based on the electrodeposition of gold nanoparticles onto the choline film modified glassy carbon electrode (GNPs/Ch/GCE). The electrochemical experiments showed that the GNPs/Ch film exhibited a distinctly higher activity for the electro-oxidation of hydrazine than GNPs with 3.4-fold enhancement of peak current. The kinetic parameters such as the electron transfer coefficient (α) and the rate of electron exchange (k) for the oxidation of hydrazine were determined. The diffusion coefficient (D) of hydrazine in solution was also calculated by chronoamperometry. The sensor exhibited two wide linear ranges of 5.0 × 10−7-5.0 × 10−4 and 5.0 × 10−4-9.3 × 10−3 M with the detection limit of 1.0 × 10−7 M (s/n = 3). The proposed electrode presented excellent operational and storage stability for the determination of hydrazine. Moreover, the sensor showed outstanding sensitivity, selectivity and reproducibility properties. All the results indicated a good potential application of this sensor in the detection of hydrazine. 相似文献
6.
Maria D.L. OliveiraAuthor VitaeDulcinéia S.P. AbdallaAuthor Vitae Daniel F. GuilhermeAuthor VitaeTanize E.S. FaulinAuthor Vitae Cesar A.S. AndradeAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):775-781
Monoclonal antibodies (MAb) have been commonly applied to measure LDL in vivo and to characterize modifications of the lipids and apoprotein of the LDL particles. The electronegative low density lipoprotein (LDL−) has an apolipoprotein B-100 modified at oxidized events in vivo. In this work, a novel LDL− electrochemical biosensor was developed by adsorption of anti-LDL− MAb on an (polyvinyl formal)-gold nanoparticles (PVF-AuNPs)-modified gold electrode. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to characterize the recognition of LDL−. The interaction between MAb-LDL− leads to a blockage in the electron transfer of the [Fe(CN)6]4−/K4[Fe(CN)6]3− redox couple, which may could result in high change in the electron transfer resistance (RCT) and decrease in the amperometric responses in CV analysis. The compact antibody-antigen complex introduces the insulating layer on the assembled surface, which increases the diameter of the semicircle, resulting in a high RCT, and the charge transferring rate constant κ0 decreases from 18.2 × 10−6 m/s to 4.6 × 10−6 m/s. Our results suggest that the interaction between MAb and lipoprotein can be quantitatively assessed by the modified electrode. The PVF-AuNPs-MAb system exhibited a sensitive response to LDL−, which could be used as a biosensor to quantify plasmatic levels of LDL−. 相似文献
7.
Aptamer-based colorimetric biosensing of dopamine using unmodified gold nanoparticles 总被引:1,自引:0,他引:1
Yu ZhengAuthor Vitae Yong WangAuthor Vitae Xiurong YangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):95-99
A simple, sensitive and selective colorimetric biosensor for the detection of dopamine (DA) was demonstrated with a 58-mer dopamine-binding aptamer (DBA) as recognition element and unmodified gold nanoparticles (AuNPs) as probes. Upon the addition of DA, the conformation of DBA would change from a random coil structure to a rigid tertiary structure like a pocket and this change has been demonstrated by circular dichroism spectroscopic experiments. Besides, the conformational change of DBA could facilitate salt-induced AuNP aggregation and lead to the color change of AuNPs from red to blue. The calibration modeling showed that the analytical linear range covered from 5.4 × 10−7 M to 5.4 × 10−6 M and the corresponding limit of detection (LOD) was 3.6 × 10−7 M. Some common interferents such as 3,4-dihydroxyphenylalanine (DOPA), catechol, epinephrine (EP), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and ascorbic acid (AA) showed no or just a little interference in the determination of DA. 相似文献
8.
Xue YanAuthor VitaeXiangjie BoAuthor Vitae Liping GuoAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):837-842
In this work, an electrochemical sensor based on ordered mesoporous carbon (OMC) for the amperometric detection of isoniazid was developed. OMC was dispersed in a solution of Nafion, and the suspension was modified onto the surface of glassy carbon (GC) electrode. Cyclic voltammetry and amperometry were used to investigate the electrochemical behaviors of isoniazid on Nafion-OMC modified electrode (Nafion-OMC/GC). The results indicate that OMC can facilitate the electrochemical oxidation of isoniazid with a great decrease of overpotential in pH 7.0 phosphate buffer solution. The proposed biosensor provides excellent performance towards the determination of isoniazid with a high sensitivity of 0.031 μA/μM, a low detection limit of 8.4 × 10−8 M and wide linear range from 1.0 × 10−7 M to 3.7 × 10−4 M at +0.20 V vs. Ag/AgCl. The method was successfully applied to the determination of isoniazid tablets with satisfying results. All the results suggest that Nafion-OMC/GC electrode is a potential candidate for a stable and efficient electrochemical sensor to detect isoniazid. 相似文献
9.
Yu WangAuthor Vitae XueYan HuAuthor VitaeLei WangAuthor Vitae ZhuoBin ShangAuthor VitaeJianBin ChaoAuthor Vitae WeiJun JinAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):126-131
A new acridine fluoroionophore containing two diethanolamine ligands, 4,5-bis(N,N-di (2-hydroxyethyl)iminomethyl)acridine (BHIA), was designed and synthesized based on the fluorophore-spacer-receptor format. And its fluorescent sensing behavior towards metal ions was investigated in buffered aqueous media. The presence of Cd2+ induces the formation of a 1:1 ligand/metal complex at neutral pH, which exhibits enhanced emission at 454 nm. The fluorescence intensity is linear with the Cd2+ concentration in the range of 1.0 × 10−6 to 3.0 × 10−5 M (R = 0.9967). Experimental results show a low interference response towards other metal ions. The selective switch-on fluorescence response of BHIA to Cd2+ makes it suitable for sensing of Cd2+ in aqueous solution. The detection limit is 1.3 × 10−7 M. Moreover, the results indicated that BHIA was a reversible chemosensor for Cd2+, which makes it attractive for sensing applications. 相似文献
10.
Chandra Mouli PandeyAuthor VitaeRenu SinghAuthor Vitae Gajjala SumanaAuthor VitaeM.K. PandeyAuthor Vitae B.D. MalhotraAuthor Vitae 《Sensors and actuators. B, Chemical》2011,151(2):333-340
An electrochemical genosensor based on 1-fluoro-2-nitro-4-azidobenzene (FNAB) modified octadecanethiol (ODT) self-assembled monolayer (SAM) has been fabricated for Escherichia coli detection. The results of electrochemical response measurements investigated using methylene blue (MB) as a redox indicator reveal that this nucleic acid sensor has 60 s of response time, high sensitivity (0.5 × 10−18 M) and linearity as 0.5 × 10−18-1 × 10−6 M. The sensor has been found to be stable for about four months and can be used about ten times. It is shown that water borne pathogens like Klebsiella pneumonia, Salmonella typhimurium and other gram-negative bacterial samples has no significant effects in the response of this sensor. 相似文献
11.
Jiadong HuangAuthor Vitae Xiuming ZhangAuthor VitaeSu LiuAuthor Vitae Qing LinAuthor VitaeXiaorui HeAuthor Vitae Xianrong XingAuthor VitaeWenjing LianAuthor Vitae Di TangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,152(2):292-298
4-Nonylphenol (4-NP) was reported to affect the health of wildlife and humans through altering endocrine function. A novel electrochemical sensor for sensitive and fast determination of 4-NP was developed. Titanium oxide (TiO2) nanoparticles and gold nanoparticles (AuNPs) were introduced for the enhancement of electron conduction and sensitivity. 4-NP-imprinted functionalized AuNPs composites with specific binding sites for 4-NP was modified on electrode. The resulting electrodes were characterized by cyclic voltammetry (CV). Rebinding experiments were carried out to determine the specific binding capacity and selective recognition. The linear range was over the range from 4.80 × 10−4 to 9.50 × 10−7 mol L−1, with the detection limit of 3.20 × 10−7 mol L−1 (S/N = 3). The sensor was successfully employed to detect 4-NP in real samples. 相似文献
12.
Yao ZhangAuthor VitaeXiumei SunAuthor Vitae Nengqin JiaAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):527-532
A promising material of poly(lactic-co-glycolic acid) (PLGA) and, room temperature ionic liquid (ILs) (1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) was firstly used as an immobilization matrix to entrap proteins and its bioelectrochemical properties were studied. Direct electrochemistry and electrocatalytic behaviors of hemoglobin (Hb) entrapped in the PLGA/ILs composite film on the surface of glass carbon electrode were investigated. UV-vis spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the composite film. The obtained results demonstrated that the Hb molecule in the film kept its native structure and showed its good electrochemical behavior. A pair of well-defined redox peaks of Hb was obtained at the Hb/PLGA/ILs composite film-modified GC electrode through direct electron transfer between the protein and the underlying electrode. The proposed biosensor showed good reproducibility and high sensitivity to H2O2 with the detection limit of 2.37 × 10−7 M (S/N = 3). In the range of 5.0 × 10−6 to 8.05 × 10−3 M, the catalytic reduction current of H2O2 was proportional to its concentration. The apparent Michaelis-Menten constant of Hb in the PLGA/ILs composite film was estimated to be 0.069 mM, showing its high affinity. 相似文献
13.
Fei TanAuthor VitaePolly H.M. LeungAuthor Vitae Zong-bin LiuAuthor Vitae Yu ZhangAuthor VitaeLidan XiaoAuthor Vitae Weiwei YeAuthor VitaeXin ZhangAuthor Vitae Li YiAuthor VitaeMo YangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):328-335
In this article, a PDMS microfluidic immunosensor integrated with specific antibody immobilized alumina nanoporous membrane was developed for rapid detection of foodborne pathogens Escherichia coli O157:H7 and Staphylococcus aureus with electrochemical impedance spectrum. Firstly, antibodies to the targeted bacteria were covalently immobilized on the nanoporous alumina membranes via self assembled (3-glycidoxypropyl)trimethoxysilane (GPMS) silane. Then, the impedance spectrum was recorded for bacteria detection ranging from 1 Hz to 100 kHz. The maximum impedance amplitude change for these two food pathogens was around 100 Hz. This microfluidic immunosensor based on nanoporous membrane impedance spectrum could achieve rapid bacteria detection within 2 h with a high sensitivity of 102 CFU/ml. Cross-bacteria experiments for E. coli O157:H7 and S. aureus were also explored to testify the specificity. The results showed that impedance amplitude at 100 Hz had a significant reduction in binding of bacteria when the membrane was exposed to non-specific bacteria. 相似文献
14.
Jahan Bakhsh RaoofAuthor Vitae Reza OjaniAuthor VitaeSeyed Mahdi GolabiAuthor Vitae Ezat Hamidi-AslAuthor VitaeMohammad Saeid HejaziAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(1):195-201
Development of an electrochemical biosensor based on peptide nucleic acid (PNA) probe for detection of target DNA sequence and single nucleotide mutation in p53 tumor suppressor gene corresponding oligonucleotide using methylene blue (MB) as an electrochemical indicator is described. The interaction between MB and short sequence of p53, one of the most important tumor suppressor genes due to its dysfunction in the majority of human cancers, was studied by differential pulse voltammety (DPV). Probe modified electrode was prepared by self-assembled monolayer (SAM) formation of thiolated PNA molecules on the surface of gold electrode (GE). The hybridization of PNA probe with target DNA was performed in solution to form PNA-DNA hybrid on the surface of the GE. A significant increase in the reduction signal of MB was observed upon hybridization of the probe with the complementary DNA. The selectivity of the biosensor was studied using noncomplementary oligonucleotides. Furthermore, our results confirmed the ability of the sensor to detect single base mismatch in the sample oligonucleotide. The influence of probe concentration on the effective discrimination against noncomplementary sequence and point mutation was also investigated. Diagnostic performance of the biosensor is described and the detection limit is found 6.82 × 10−10 M. The electrochemical impedance spectroscopy was also employed to further investigate the sensor function. 相似文献
15.
16.
Chia-Wei ChangAuthor VitaeJiunn-Der LiaoAuthor Vitae Yin-Yi LinAuthor VitaeChih-Chiang WengAuthor Vitae 《Sensors and actuators. B, Chemical》2011,153(1):271-276
Well-ordered nano-mechanically made Au-cavities array (nAu) is tailored as a functional surface with high density tip-to-tip cavities, adjustable indentation depths, and a number of edges within the nanostructures. In this study, the nAu was fabricated by a physical way and utilized as a characterization tool with the advantage of preventing samples from chemical or residual contaminations. Two types of molecular probe solutions: 5,5′-dithio-bis-(2-nitrobenzoic acid) (DTNB) and Rhodamine 6G (R6G) were evaluated. For DTNB solution, the chemically adsorbed monolayer was formed upon the nAu, which resulted in the effect of surface enhanced Raman scattering (SERS), mainly induced by the combined chemical and electromagnetic effects. Within the range of 1 × 10−23 to 3.2 × 10−22 mole, Raman intensity and the quantity of DTNB molecules exhibited a sharp exponential relationship. For R6G solution within the equivalent nAu and the identical range, the relationship exhibited nearly linear; however, within an extended range of 1 × 10−23 to 3.2 × 10−21 mole, a moderate exponential relationship was obtained. The enhancement factors for detecting DTNB and R6G solutions using the nAu could be optimized to 1.62 × 108 and 4.60 × 107, respectively. 相似文献
17.
Yongyan TanAuthor VitaeJinqing KanAuthor Vitae Shengqi LiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,152(2):285-291
A novel amperometric biosensor for the determination of catechol was developed accordingly to the electrochemical template procedure. The optimum fabricating conditions of the biosensor were studied. The resulting biosensor with the limit of less than 0.05 μM can be used for detection of catechol in the linear range of 2.5-140 μM. The maximum response current (Imax) and the Michaelis-Menten constant (k′m) are 3.08 μA and 77.52 μM, respectively. The activation energy (Ea) of the polyphenol oxidase (PPO) catalytic reaction is 25.56 kJ mol−1 in the B-R buffer. The stability of the PANI-CA biosensor fabricated with the electrochemical template process (retains 86% of the original activity after four months) is much higher than that fabricated with one-step and two-step processes (retains 75% of the original activity after four months). The effects of potential and pH on the response current of the biosensor are also described. 相似文献
18.
Fatemeh AbbasitabarAuthor VitaeVali Zare-ShahabadiAuthor Vitae Mojtaba ShamsipurAuthor VitaeMorteza AkhondAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):181-186
A very sensitive and reversible optical chemical sensor based on dithizone as chromoionophore immobilized within a plasticized carboxylated PVC film for Zn2+ determination is described. At optimum conditions (i.e. pH 5.0), the proposed sensor displays a linear response to Zn2+ over 5.0 × 10−8-5.0 × 10−6 mol L−1 range. This range was improved to 2.5 × 10−8-5.8 × 10−5 mol L−1 range by applying principle component-feed forward artificial neural network with back-propagation training algorithm (PC-ANNB). Detection limit of 8.0 × 10−9 mol L−1 was obtained. The sensor is fully reversible within the dynamic range and the response time (t95%) is approximately 4 min under batch conditions. In addition to its high stability and reproducibility, the sensor shows good selectivity towards Zn2+ ion with respect to common metal cations. The sensor was successfully applied for determination of Zn2+ ion in hair sample. 相似文献
19.
Veronica Paz ZaniniAuthor Vitae Beatriz López de MishimaAuthor VitaeVelia SolísAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):75-80
A biosensor based on the immobilization of lactate oxidase (LOx) on a glassy carbon electrode modified with laponite/chitosan hydrogels for the quantification of l-lactate in alcoholic beverages and dairy products is presented. Ferrocene-methanol (FcMe) is used as artificial mediator. The purpose of this work is to determine the best hydrogel composition from the analytical point of view. The characterization of the hydrogels was carried out by CV, amperometry and EIS. According to permeabilities and charge transfer resistances for ferrocyanide (used as molecular probe) as well as the enzymatic behavior of the enzyme for l-lactate, the best laponite/chitosan mass ratio found was 25/50. The distinct features of the bioelectrode are its long stability, its ability to reject or minimize most interferents including ascorbic acid, and its excellent analytical response, which allowed the reduction of the enzyme content below 0.5 U, for a sensitivity of (0.326 ± 0.003) A cm−2 M−1, with a time response lower than 5 s and a detection limit of (3.8 ± 0.2) × 10−6 M. Our l-lactate biosensor was validated by comparison with a standard spectroscopic method. 相似文献
20.
T. Del RossoAuthor VitaeE. GiorgettiAuthor Vitae G. MargheriAuthor VitaeA. RindiAuthor Vitae M. Muniz-MirandaAuthor Vitae A. CarloniAuthor VitaeF. PavoneAuthor Vitae P. FabbrizziAuthor VitaeS. CicchiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):46-52
This work reports on the Cu2+ chemosensing behaviour of self-organized micro-array structures of a novel donor-acceptor bichromophoric compound anchored onto Ag nanoisland films. The system exhibits quenching of the fluorescence in the presence of Cu2+ ions, with detection range extending from 2 × 10−8 M up to 3 × 10−6 M and limit of detection (LOD) of 8 × 10−9 M. The quenching of fluorescence is accompanied by a quenching of SERS signal from the metal-organic structure, which is consistent with an electron transfer between the copper cation and the organic moiety. The self-organization property of the sensing complexes into micrometric arrays offers great potential for miniaturization and future development of Cu2+ detection systems based on real-time observation of fluorescence or SERS quenching by fluorescence microscopy or microRaman spectroscopy. 相似文献