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1.
《Electroanalysis》2017,29(11):2507-2515
In the present study, a novel enzymatic glucose biosensor using glucose oxidase (GOx) immobilized into (3‐aminopropyl) triethoxysilane (APTES) functionalized reduced graphene oxide (rGO‐APTES) and hydrogen peroxide sensor based on rGO‐APTES modified glassy carbon (GC) electrode were fabricated. Nafion (Nf) was used as a protective membrane. For the characterization of the composites, Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffractometer (XRD), and transmission electron microscopy (TEM) were used. The electrochemical properties of the modified electrodes were investigated using electrochemical impedance spectroscopy, cyclic voltammetry, and amperometry. The resulting Nf/rGO‐APTES/GOx/GC and Nf/rGO‐APTES/GC composites showed good electrocatalytical activity toward glucose and H2O2, respectively. The Nf/rGO‐APTES/GC electrode exhibited a linear range of H2O2 concentration from 0.05 to 15.25 mM with a detection limit (LOD) of 0.017 mM and sensitivity of 124.87 μA mM−1 cm−2. The Nf/rGO‐APTES/GOx/GC electrode showed a linear range of glucose from 0.02 to 4.340 mM with a LOD of 9 μM and sensitivity of 75.26 μA mM−1 cm−2. Also, the sensor and biosensor had notable selectivity, repeatability, reproducibility, and storage stability.  相似文献   

2.
《Electroanalysis》2017,29(5):1258-1266
The nanoporous graphene papers (NGPs) was prepared by the hard‐template method. The Pt−Pd modified NGPs hybrid was prepared by the self‐assembly method. Then a glassy carbon electrode (GCE) modified with Pt−Pd bimetallic nanoparticles‐functionalized nanoporous graphene composite has been prepared for the electrochemical determination of Xanthine (XA). The Pt−Pd/NGPs hybrid was characterized by transmission electron microscopy, scanning electron microscope and X‐ray diffraction. The electrochemical behavior of XA on Pt−Pd/NGPs/GCE was investigated by cyclic voltammetry and amperometric i‐t. The Pt−Pd/NGPs modified electrode exhibited remarkably electrocatalytic activity towards the oxidation reaction of XA in phosphate buffer solution (pH=5.5). Under the optimal conditions, the determination of XA was accomplished by using amperometric i‐t, the linear response range from 1.0×10−5∼1.2×10−4 M. The detection limit was 3.0×10−6 M (S/N=3). The proposed modified electrode showed good sensitivity, selectivity, and stability with applied to determine XA in human urine.  相似文献   

3.
《Electroanalysis》2017,29(2):635-642
An electrochemical sensor for paracetamol (PC) based on the hexacyanoferate(III) intercalated Ni−Al layered double hydroxide (Ni−Al−HCF) was presented. The as‐prepared LDH structurally and morphologically was characterized by scanning electron microscopy, X‐ray diffraction, and Fourier transform IR. Electrochemical studies revealed that Ni−Al−HCF film modified glassy carbon (GC) electrode exhibited remarkable electrocatalytic activity toward the oxidation of paracetamol. The electrochemical behavior of PC on the Ni−Al−HCF film was investigated in detail. Under optimum experimental conditions, the electrocatalytic response of the modified GC electrode was linear in the PC concentration range 3×10−6−–1.5×10−3 mol L−1, with a detection limit of 8×10−7 mol L−1 (S/N=3), using hydrodynamic amperometry. In addition, the modified electrode exhibited good reproducibility, long‐term stability and anti‐interference property. The fabricated sensor was successfully applied to determination of PC in various pharmaceutical preparations such as tablets, oral solution, and oral drops. Finally, the method was validated by the analysis of paracetamol spiked human serum samples, and good recoveries were obtained in the range of 99.2–103 %.  相似文献   

4.
The present study describes the fabrication of a sensitive amperometric sensor for the determination of persulfate. The immobilization surface was prepared by modifying a glassy carbon (GC) electrode with a nanocomposite containing ruthenium oxide (RuOx) nanoparticles and thionine (TH) or celestin blue (CB). The modified electrodes indicated excellent electrocatalytic activity toward persulfate reduction at a potential of +0.1 V. The proposed sensor showed detection limits of 1.46 µM for the GC/RuOx/TH modified electrode and 2.64 µM for the GC/RuOx/CB modified electrode. The sensitivities were obtained as 3 nA µM?1 at a concentration range of 10 µM to 11 mM for the GC/RuOx/TH modified electrode and 1 nA µM?1 at a concentration range of 10 µM to 6 mM for the GC/RuOx/CB modified electrodes.  相似文献   

5.
Potentiostatic anodization was developed to synthesize copper oxide/copper (CuxO/Cu, x=1,2) electrode with nano structure for sensitive non-enzymatic glucose detection. At a catalytic potential of 0.55 V, the CuO/Cu electrode presented a high sensitivity of 2954.38 μA mM−1 cm−2 to glucose and a linear range of 0.1 mM to 1.3 mM. The response time is less than 3 s with addition of 0.1 mM glucose. The CuO/Cu electrode above was anodized in 1M KOH solution at −100 mV and the morphology was compact nanoparticles and sparsely dispersed nanosheets, which enlarged the surface area and provided abundant electrocatalytic active sites. Compared the sensing property of electrodes with different morphologies, it indicated that nanostructure was significant to the efficient glucose catalytic oxidation process and it could be regulated by changing the potential and electrolyte concentration during anodization.  相似文献   

6.
Conductive polymeric [NiII(teta)]2+ (teta=C‐meso‐5,5,7,12,12,14‐hexamethyl‐1,4,8,11‐tetra‐azacyclotetradecane) films (poly(Ni)) have been deposited on the surface of glassy carbon (GC), Nafion (Nf) modified GC (GC/Nf) and Nf stabilized Ag and Au nanoparticles (NPs) modified GC (GC/Ag‐Nf and GC/Au‐Nf) electrodes. The cyclic voltammogram of the resulting electrodes, show a well defined redox peak due to oxidation and reduction of poly(Ni) system in 0.1 M NaOH. They show electrocatalytic activity towards the oxidation of glucose. AFM studies reveal the formation of poly(Ni) film on the modified electrodes. Presence of metal NPs increases electron transfer rate and electrocatalytic oxidation current by improving the communication within the Nf and poly(Ni) films. In the presence of metal NPs, 4 fold increase in current for glucose oxidation was observed.  相似文献   

7.
《Electroanalysis》2018,30(1):187-193
This work reports about the performance of a Ni/Cu‐modified screen printed electrodes (SPE/Ni/Cu), prepared by physical vapor deposition (PVD) in an oblique angle configuration (OAD), for non‐enzymatic glucose sensing applications. SPE/Ni/Cu electrodes showed an excellent reversibility and a catalytic behavior for detection of glucose that were controlled by the diffusion of reactants up to the active sites at the electrode surface. The study with a flow injection analysis (FIA) setup of the main experimental variables affecting the detection process has shown that the developed electrode system had an excellent glucose sensitivity of 1.04 A M−1cm−2 (R2:0.999), a linear response up to 1 mM, a limit of detection of 0.33 μM and a time of analysis of ca. 30 s per sample. The selectivity of the sensor was checked against various interferences, including ascorbic acid, uric acid, acetaminophen and other sugars, in all cases with excellent results. The feasibility of using this sensor for practical applications was successfully confirmed by determining the glucose concentration in different commercial beverages.  相似文献   

8.
《Electroanalysis》2017,29(4):1014-1021
An electrochemical device was developed for the simultaneous determination of sulfamethoxazole (SMX) and trimethoprim (TMP) using differential pulse voltammetry and glassy carbon (GC) electrodes modified with reduced graphene oxide (rGO) and silver nanoparticle (AgNP) composites, synthesised using both chemical and electrochemical methods. The morphology and electrochemical behaviour of the GC electrodes modified with the rGO/AgNP (chemical method) and rGO‐AgNP (electrochemical method) composites were characterised by scanning electron microscopy and cyclic voltammetry. These techniques demonstrated that, in both methods, the graphene oxide was modified by the AgNPs, and the composite synthesised by the electrochemical method showed a better dispersion of the nanoparticles, resulting in an increase in the surface area compared to the rGO/AgNP composite. The GC/rGO‐AgNP electrode was evaluated and optimised for the simultaneous determination of SMX and TMP, achieving detection limits of 0.6 μmol L−1 for the SMX and 0.4 μmol L−1 for the TMP. The proposed GC/rGO‐AgNP electrochemical device was successfully applied to the simultaneous determination of SMX and TMP in wastewaters samples.  相似文献   

9.
A high-performance amperometric glucose biosensor was developed, based on immobilization of glucose oxidase (GOx) on a copper (Cu) nanoparticles/chitosan (CHIT)/carbon nanotube (CNT)-modified glassy carbon (GC) electrode. The Cu and CNT had a synergistic electrocatalytic effect toward the reduction of hydrogen peroxide in the matrix of biopolymer CHIT. The Cu/CHIT/CNT modified GC electrode could amplify the reduction current of hydrogen peroxide greatly. Besides, the Cu/CHIT/CNT modified GC electrode reduces hydrogen peroxide at a much lower applied potential and inhibit the responses of interferents. With GOx as an enzyme model, a new glucose biosensor was fabricated. The sensitivity of the sensor is due not only to the large microscopic area but also to the high efficiency of transformation of H2O2 generated by enzymatic reaction to current signal. The biosensor exhibited excellent sensitivity (the detection limit is down to 0.02 mM), fast response time (less than 4 sec), wide linear range (from 0.05 to 12 mM), and perfect selectivity. Correspondence: Wanzhi Wei, State key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China  相似文献   

10.
The study presents a novel paracetamol (PA) sensor based on Pd nanoparticles (PdNPs) deposited on carboxylated graphene oxide (GO?COOH) and nafion (Nf) modified glassy carbon electrode (GCE). The morphologies of the as prepared composites were characterized using high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and fourier transform infrared spectroscopy (FTIR). The experimental results demonstrated that Nf/GO?COOPd displayed excellent electrocatalytic response to the oxidation PA. The linear range was 0.04–800 μM for PA with limit of detection of 0.012 μM and excellent sensitivity of 232.89 μA mM?1 cm?2. By considering the excellent performance of Nf/GO?COOPd composite such as wider linear range, lower detection, better selectivity, repeatability, reproducibility, and storage stability, the prepared composite, especially GO?COOH support, with satisfactory electrocatalytic properties was a promising material for the modification of electrode material in electrochemical sensor and biosensor field.  相似文献   

11.
IntroductionThelevelofglucoseinbloodorurineindicateshyper andhypoglycaemia ,bothofwhichcanresultfromavarietyofendocrinedisorders .1 4 Therapidandreliabledetermi nationofglucoselevelisaroutineprojectinclinicchem istry.Urinesamplesaresaferandmoreconvenientthanbloodones .Meanwhile ,theconcentrationofglucoseinserumiscloselyassociatedwiththatinurine .2 4 Eventhoughglucoseelectrodeshavebeensuccessfullyusedinseruminclinicalapplication ,thequestionstillremainedofhowtodetecttheglucoselevelinurine ,wh…  相似文献   

12.
《Electroanalysis》2018,30(8):1828-1836
Synthesis of nanomaterials using cheap and highly efficient material is an important aspect of nanotechnology. In this present work, we have used the carbon black (CB) as a highly conductive and inexpensive carbonaceous material for the fabrication of the electrochemical sensor. However, the poor dispersion in water obstructs the usage of CB in electrochemical sensor and biosensor applications. Hence, the CB was functionalized by simple reflux method and the functionalized CB (f‐CB) nanospheres hybrids with hydrothermally synthesized MoS2 nanoclusters by simple ultrasonication process. In addition, the various suitable spectrometric techniques used to probe the surface morphology and chemical modification of the prepared materials. The prepared MoS2 and f‐CB nanohybrids (f‐CB/MoS2) applied for the electrocatalytic reduction of toxic chloramphenicol (CAP). Fascinatingly, the f‐CB/MoS2 modified electrode showed a competitive electrocatalytic performance comparing with other modified electrodes. At the optimized condition, the sensor exhibited the LOD about 0.002 μM, wider linear range 0.015 to 1370 μM with the sensitivity of 3400 μA μM−1 cm−2 for the determination of CAP. Moreover, the practical viability of the sensor was exploited in milk powder and honey samples.  相似文献   

13.
《Electroanalysis》2017,29(11):2591-2601
In present work, reduced graphene oxide nanosheets (rGO) decorated with trimetallic three‐dimensional (3D) Pt−Pd−Co porous nanostructures was fabricated on glassy carbon electrode (Pt−Pd−Co/rGO/GCE). First, GO suspension was drop‐casted on the electrode surface, then GO film reduction was carried out by cycling the potential in negative direction to form the rGO film modified GCE (rGO/GCE). Then, electrodeposition of the cobalt nanoparticles (CoNPs) as sacrificial seeds was performed onto the rGO/GCE by using cyclic voltammetry. Afterward, Pt−Pd−Co 3D porous nanostructures fabrication occurs through galvanic replacement (GR) method based on a spontaneous redox process between PtCl2, PdCl2, and CoNPs. The morphology and structure of the Pt−Pd−Co/rGO porous nanostructure film was characterized by scanning electron microscopy, energy dispersive spectroscopy and X‐ray diffraction method. The performance of the prepared electrode was investigated by various electrochemical methods including, cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic activity of the as‐prepared modified electrode with high surface areas was evaluated in anodic oxidation of ethylene glycol. The study on electrocatalytic performances revealed that, in comparison to various metal combinations in modified electrodes, trimetallic Pt−Pd−Co/rGO/GCE exhibit a lower onset potential, significantly higher peak current density, high durability and stability for the anodic oxidation of ethylene glycol. The excellent performances are attributed to the rGO as catalysts support and resulting synergistic effects of the trimetallic and appropriate characteristics of the resulted 3D porous nanostructures. Moreover, the influence of various concentrations of ethylene glycol, the potential scan rate and switching potential on the electrode reaction, in addition, long‐term stability have been studied by chronoamperometric and cyclic voltammetric methods.  相似文献   

14.
《Electroanalysis》2017,29(8):1985-1993
Polytyramine (PT) has been electro‐deposited onto multi‐walled carbon nanotube (MWCNT) modified glassy carbon (GC) electrodes via oxidation of tyramine in 0.1 M H3PO4 by cycling the potential over the range of −400 mV to 1300 mV (versus Ag/AgCl). The reactivity of the resulting chemically‐modified electrodes was characterized using cyclic voltammetry in the presence and absence of reduced nicotinamide adenine dinucleotide (NADH). The modified electrodes displayed electrochemical activity due to the formation of quinone species and were catalytically active towards NADH oxidation by lowering the oxidation peak potential by 170 mV compared to the value of the MWCNT modified electrode with a peak potential of 180±10 mV (versus Ag/AgCl). The MWCNT/PT surface was further characterized using SEM and XPS methods, which indicated that a thin polymeric film had been formed on the electrode surface. The present work demonstrates the advantage of using PT as a platform that combines both the immobilization of alcohol dehydrogenase (ADH) and the mediation of NADH oxidation at a low overpotential essential to the design of high performance ethanol biosensors, all within an easily electropolymerizable film. The resulting biosensor displayed an ethanol sensitivity of 4.28±0.06 μA mM−1 cm−2, a linear range between 0.1 mM and 0.5 mM and a detection limit of 10 μM.  相似文献   

15.
A novel Prussian blue/copper‐gold bimetallic nanoparticles hybrid film modified electrode was prepared by electrochemical deposition on a glassy carbon electrode (PB/Cu‐AuNPs/GCE). Morphology and electrochemistry of this electrode were studied by UV‐vis spectroscopy, scanning electron microscopy, X‐ray diffraction, cyclic voltammetry and electrochemical impedance spectroscopy. The sensor showed significantly better electrocatalytic activity for the reduction of hydrogen peroxide in comparison with the single PB/GCE and PB/AuNPs/GCE. This was attributed to the synergistic effect of PB and Cu‐Au bimetallic nanoparticles. Also, the sensor demonstrated an overall high level of performance for the analysis of H2O2 in the concentration range from 0.002 to 0.84 mM.  相似文献   

16.
《Electroanalysis》2018,30(3):474-478
A non‐enzymatic electrochemical glucose sensor based on a Cu‐based metal‐organic framework (Cu‐MOF) modified electrode was developed. The Cu‐MOF was prepared by a simple ionothermal synthesis, and the characterizations of the Cu‐MOF were studied by Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), single‐crystal X‐ray powder diffraction (SCXRD), and X‐ray powder diffraction (XRD). Electrochemical behaviors of the Cu‐MOF modified electrode to glucose were measured by differential pulse voltammetry (DPV). The electrochemical results showed that the Cu‐MOF modified electrode exhibited an excellent electro‐catalytic oxidation towards glucose in the range of 0.06 μM to 5 mM with a sensitivity of 89 μA/mM cm2 and a detection limit of 10.5 nM. Moreover, the fabricated sensor showed a high selectivity to the oxidation of glucose in coexistence with other interferences. The sensor was satisfactorily applied to the determination of glucose in urine samples. With the significant electrochemical performances, MOFs may provide a suitable platform in the construction of kinds of electrochemical sensors and/or biosensors and hold a great promise for sensing applications.  相似文献   

17.
《Electroanalysis》2017,29(4):1103-1112
Three dimensional graphene‐multiwalled carbon nanotube nano composite (3DG/MWCNTs−Nc) was synthesized by simple hydrothermal method for the amperometric determination of caffeic acid (CA). The prepared nanocomposite was characterized by scanning electron microscopic technique (SEM), ultraviolet‐visible spectroscopy (UV), Raman spectroscopy and infrared spectroscopy (IR). Moreover, the interfacial electron transfer properties of the modified electrode were carried out by the electro chemical impedance spectroscopy (EIS). Besides, the electro chemical performance of the modified electrode was carried out by the cyclic voltammetry (CV) and amperometric (i‐t ) technique. The proposed electrode was exhibited an enhanced electrocatalytic activity towards the detection of CA. Under the optimal condition, the 3DG/MWCNTs−Nc modified electrode displayed a linear range from 0.2 to 174 μM, detection limit (LOD) 17.8 nM and sensitivity of 5.8308 μA μM−1 cm−2 and on applied potential + 0.2 V. These result showed, 3DG/MWCNTs−Nc modified electrodes showed good repeatability, reproducibility, and higher stability. In addition, the fabricated electrode was then successfully used to determine the CA in real samples with satisfactory recoveries. Which suggests that the 3DG/MWCNTs−Nc as a robust sensing materials for the electrochemical detection of CA.  相似文献   

18.
《Electroanalysis》2017,29(12):2689-2697
Stable and well dispersed nickel nanoparticles (NiNPs) were fabricated and embedded in a novel polymer sulfonate and benzimidazole functionalized poly (arylene ether ketone) (S‐BI‐PAEK) film. After drop‐casting the mixed solution of S‐BI‐PAEK and NiSO4 on glassy carbon electrode (GCE) surface, the uniformly distributed NiNPs were formed and stably embedded in S‐BI‐PAEK film by in‐situ electrochemical reduction method. The embedment and well dispersity of NiNPs in S‐BI‐PAEK film was probably attributed to the strong chelation of sulfonate and benzimidazole functional groups contained in S‐BI‐PAEK toward Ni2+ ions, as well as the transferability of Ni2+ ions in S‐BI‐PAEK film. The NiNPs/S‐BI‐PAEK composite film was characterized by scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDS), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). It exhibited good electrocatalytic activity toward glucose oxidation in 0.1 mol L−1 NaOH solution with high stability. The NiNPs/S‐BI‐PAEK/GCE showed a fast amperometric response with a wide linear range from 1 μM to 4 mM and a low detection limit of 200 nmol L−1 (S/N=3) for the determination of glucose by amperometry at a potential of 0.55 V. Finally it was successfully employed to determine glucose in human serum. Therefore, the novel fabrication method of nickel nanoparticles was promising for the future development of non‐enzymatic glucose sensor.  相似文献   

19.
The simple, fast and highly sensitive anodic stripping voltammetric detection of As(III) at a gold (Au) nanoparticle‐modified glassy carbon (GC) (nano‐Au/GC) electrode in HCl solution was extensively studied. The Au nanoparticles were electrodeposited onto GC electrode using chronocoulometric technique via a potential step from 1.1 to 0 V vs. Ag|AgCl|NaCl (sat.) in 0.5 M H2SO4 containing Na[AuCl4] in the presence of KI, KBr, Na2S and cysteine additives. Surfaces of the resulting nano‐Au/GC electrodes were characterized with cyclic voltammetry. The performances of the nano‐Au/GC electrodes, which were prepared using different concentrations of Na[AuCl4] (0.05–0.5 mM) and KI additive (0.01–1.0 mM) at various deposition times (10–30 s), for the voltammetric detection of As(III) were examined. After the optimization, a high sensitivity of 0.32 mA cm?2 μM?1 and detection limit of 0.024 μM (1.8 ppb) were obtained using linear sweep voltammetry.  相似文献   

20.
《Electroanalysis》2017,29(8):1876-1886
A facile chemical solution deposition via two‐step spin coating technique was used to fabricate nano‐particulate novel Sn doped Co3O4 thin film for glucose sensor and fuel cell applications. Substitution of Sn into Co3O4 host lattice lead to a remarkable increase in the electrocatalytic activity of the Co3O4 electrode material. Film thickness played a significant role in enhancing the charge transferability of the electrode as was observed from electrochemical impedance spectroscopy (EIS). The best sensor exhibited two wide linear response ranges (2 μM up to ∼0.5 mM and 0.6 mM up to ∼5.5 mM respectively) with sensitivities of 921 and 265 μA cm−2 mM−1 respectively and low limit of detection of 100 nM (S/N=3). The sensor was very selective towards glucose in the presence of various interference and showed long term stability. Moreover, the developed thin film modified electrode could generate one electron current in nonenzymatic fuel cell setup at room temperature.  相似文献   

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