A novel non-enzymatic glucose sensor modified with Fe2O3 nanowire arrays

Fe(2)O(3) was generally considered to be biologically and electrochemically inert, and its electrocatalytic functionality has been rarely realized directly in the past. In this work, Fe(2)O(3) nanowire arrays were synthesized and electrochemically characterized. The as prepared Fe(2)O(3) nanomaterial was proved to be an ideal electrode material due to the intrinsic peroxidase-like catalytic activity. The Fe(2)O(3) nanowire array modified glucose sensor exhibited excellent biocatalytic performance towards the oxidation of glucose with a response time of <6 s, a linear range between 0.015-8 mM, and sensitivity of 726.9 μA mM(-1)cm(-1). Additionally, a high sensing selectivity towards glucose oxidation in the presence of ascorbic acid (AA) and dopamine (DA) has also been obtained at their maximum physiological concentrations, which makes the Fe(2)O(3) nanomaterial promising for the development of effective electrochemical sensors for practical applications.     

A novel sensitive non-enzymatic glucose sensor

Cu nanoclusters were electrochemically deposited on the film of a Nafion-solubilized multi-wall carbon nanotubes (CNTs) modified glassy carbon electrode (CNTs-GCE), which fabricated a Cu-CNTs composite sensor (Cu-CNTs-GCE) to detect glucose with non-enzyme. The linear range is 7.0×10-7 to 3.5×10-3 mol/L with a high sensitivity of 17.76μA/(mmol L), with a low detection limit 2.1×10-7 mol/L, fast response time (within 5 s), good reproducibility and stability.     

An improved sensitivity non-enzymatic glucose sensor based on a CuO nanowire modified Cu electrode

CuO nanowires have been prepared and applied for the fabrication of glucose sensors with highly enhanced sensitivity. Cu(OH)(2) nanowires were initially synthesised by a simple and fast procedure, CuO nanowires were then formed simply by removing the water through heat treatment. The structures and morphologies of Cu(OH)(2) and CuO nanowires were characterised by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The direct electrocatalytic oxidation of glucose in alkaline medium at CuO nanowire modified electrodes has been investigated in detail. Compared to a bare Cu electrode, a substantial decrease in the overvoltage of the glucose oxidation was observed at the CuO nanowire electrodes with oxidation starting at ca. 0.10 V vs. Ag/AgCl (saturated KCl). At an applied potential of 0.33 V, CuO nanowire electrodes produce high and reproducible sensitivity to glucose with 0.49 microA/micromol dm(-3). Linear responses were obtained over a concentration range from 0.40 micromol dm(-3) to 2.0 mmol dm(-3) with a detection limit of 49 nmol dm(-3) (S/N = 3). The CuO nanowire modified electrode allows highly sensitive, low working potential, stable, and fast amperometric sensing of glucose, thus is promising for the future development of non-enzymatic glucose sensors.     

A novel non-enzymatic glucose sensor based on Cu nanoparticle modified graphene sheets electrode

A novel, stable and sensitive non-enzymatic glucose sensor was developed by potentiostatically electrodepositing metallic Cu nanoparticles on graphene sheets. The electrochemical performance of the Cu-graphene sheets electrode for detection of glucose was investigated by cyclic voltammetry and chronamperometry. The Cu-graphene sheets electrode displayed a synergistic effect of copper nanoparticles and graphene sheets towards the oxidation of glucose in alkaline solution, showing higher oxidation current and negative shift in peak potential. At detection potential of 500 mV, the Cu-graphene electrode sensor presented a wide linear range up to 4.5 mM glucose with a detection limit of 0.5 μM (signal/noise = 3). In addition, the sensor responds very quickly (<2 s) with addition of glucose. Furthermore, the Cu-graphene sheets electrode exhibits high stability and selectivity to glucose, and the poisoning by chloride ion as well as interference from the oxidation of common interfering species (ascorbic, dopamine, uric acid and carbohydrate) are effectively avoided. The Cu-graphene sheets electrode allows highly selective and sensitive, stable and fast amperometric sensing of glucose, which is promising for the development of non-enzymatic glucose sensor.     

无酶葡萄糖电化学传感器的研究进展

随着各种新型材料的层出不穷及其在葡萄糖电化学传感器方面应用的发展,无酶葡萄糖电化学传感器的研制成为葡萄糖电化学传感器的另一个研究热点.本文综述了近年来无酶葡萄糖电化学传感器的研究进展,重点介绍了电流型无酶葡萄糖传感器所使用的各种电极材料,总结了最近五年各种新型结构材料在该类传感器研制方面的应用,并对无酶葡萄糖电化学传感器发展方向和趋势进行了展望.     

Phosphomolybdic acid functionalized graphene loading copper nanoparticles modified electrodes for non-enzymatic electrochemical sensing of glucose

A sensitive non-enzymatic glucose electrochemical biosensor (Cu/PMo₁₂-GR/GCE) was developed based on the combination of copper nanoparticles (CuNPs) and phosphomolybdic acid functionalized graphene (PMo₁₂-GR). PMo₁₂-GR films were modified on the surface of glassy carbon electrode (GCE) through electrostatic self-assembly with the aid of poly diallyl dimethyl ammonium chloride (PDDA). Then CuNPs were successfully decorated onto the PMo₁₂-GR modified GCE through electrodeposition. The morphology of Cu/PMo₁₂-GR/GCE was characterized by scanning electron microscope (SEM). Cyclic voltammetry (CV) and chronoamperometry were used to investigate the electrochemical performances of the biosensor. The results indicated that the modified electrode displayed a synergistic effect of PMo₁₂-GR sheets and CuNPs towards the electro-oxidation of glucose in the alkaline solution. At the optimal detection potential of 0.50 V, the response towards glucose presented a linear response ranging from 0.10 μM to 1.0 mM with a detection limit of 3.0 × 10⁻² μM (S/N = 3). In addition, Cu/PMo₁₂-GR/GCE possessed a high selectivity, good reproducibility, excellent stability and acceptable recovery, which indicating the potential application in clinical field.     

Direct electrochemical non-enzymatic assay of glucose using functionalized graphene

A non-enzymatic amperometric sensor is developed based on the graphite electrode modified with functionalized graphene for the determination of β, d (+)-glucose. Cyclic voltammetry and electrochemical impedance spectroscopy techniques are used to study the behavior. Atomic force microscopy was used to study the surface topography of the working electrode before and after its modification. The sensor enabled the direct electrochemical oxidation of β, d (+)-glucose in alkaline medium and responded linearly to the analyte over the range from 0.5?×?10^?3 to 7.5?×?10^?3?M with a limit of detection of 10?μM. The sensor is found to exhibit a better sensitivity of 28.4?μA?mM^?1?cm^?2, good stability, and shelf life. The sensitivity of the sensor to β, d (+)-glucose was not affected by the commonly co-existing interfering substances such as l-ascorbic acid, dopamine, uric acid, and acetaminophen.     

Vapor-liquid-solid grown silica nanowire based electrochemical glucose biosensor

Vapor-liquid-solid (VLS) grown silica nanowires (SiO(2)NWs) have been deposited electrophoretically on a gold electrode and utilized for covalent immobilization of glucose oxidase (GOx). Covalent binding has been achieved via 3-aminopropyltriethoxysilane (APTES) modification and N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide chemistry. Scanning electron microscopy, transmission electron microscopy and cyclic voltammetry techniques have been used to characterize SiO(2)NW and GOx/APTES/SiO(2)NW/Au bioelectrode. Electrochemical studies reveal that SiO(2)NW increases the effective electro-active surface area thus resulting in higher loading of enzyme. Response characteristics show linearity in the range of interest 25-300 mg dl(-1), with a detection limit of 11 mg dl(-1), sensitivity: 0.463 μA (mg dl(-1))(-1) and regression coefficient of 0.992.     

Fabrication of a non-enzymatic glucose sensor field-effect transistor based on vertically-oriented ZnO nanorods modified with Fe2O3

Herein, we report a non-enzymatic glucose sensor field-effect transistor (FET) based on vertically-oriented zinc oxide nanorods modified with iron oxide (Fe₂O₃-ZNRs). Compared with ZnO-based non-enzymatic glucose sensors, which show poor sensing performances, modification of ZnO with Fe₂O₃ dramatically enhances the sensing behavior of the fabricated non-enzymatic FET glucose sensor due to the excellent electrocatalytic nature of Fe₂O₃. The fabricated non-enzymatic FET sensor showed excellent catalytic activity for glucose detection under optimized conditions with a linear range up to 18 mM, detection limits down to ~ 12 μM, excellent selectivity, good reproducibility and long-term stability. Moreover, the fabricated FET sensor detected glucose in freshly drawn mouse whole blood and serum samples. The developed FET sensor has practical applications in real samples and the solution-based synthesis process is cost effective.     

Ferrocene-based novel electrochemical In sensor

A new ferrocene-based electrochemical sensor 1 for In³⁺ with amide and thiourea as binding sites was synthesized and characterized by X-ray crystal analysis. Among various metal ions, 1 displays highly selective electrochemical signal changes for In³⁺ over other metal ions, with its color changing from yellow to orange.     

MXene-based composite electrodes for efficient electrochemical sensing of glucose by non-enzymatic method

A recently discovered 2D transition titanium metal carbides also called as MXenes (Ti₃C₂T_x)-based nanocomposite was prepared with Cu₂O through wet precipitation technique, and these materials were further developed as the electrode for sensing glucose by chronoamperometry technique. The prepared MXene-Cu₂O (Ti₃C₂T_x-Cu₂O) nanocomposite was characterized by XRD, FTIR, UV–Vis spectroscopy, FE-SEM, EDAX, and Raman spectroscopy. Morphological studies of the composites revealed that the micro-octahedral shape of Cu₂O is distributed on the surface of MXene with size larger than bare Cu₂O. Further, the prepared composite material was fabricated as a sensing probe, and the electrochemical activities were examined by cyclic voltammetric analysis (CV) and chronoamperometric (CA) methods. From the CV and CA investigation, the current response was higher for the composite than the bare material (Cu₂O & MXene) in the presence of glucose. The amperometric investigation of MXene-Cu₂O composite for the detection of glucose shows a broad linear range (0.01–30 mM) with a sensitivity of 11.061/μAmM cm^?2 and a detection limit of 2.83 μM. Further, the fabricated sensor exhibits good selectivity with interfering species like NaCl, fructose, sucrose, urea, ascorbic acid, lactose, short response time, stability, good reproducibility, and compatibility with human serum sample. From the investigation, the prepared MXene-Cu₂O composite is a good candidate for the direct detection of glucose molecules and is also well suitable for clinical diagnosis.     

A glucose sensor based on glucose dehydrogenase adsorbed on a modified carbon electrode

A glucose sensor is prepared by adsorption of the mediator Meldola blue (N,N-dimethyl-7-amino-1,2-benzophenoxazinium ion, as well as glucose dehydrogenase, on the surface of a carbon electrode. The nicotinamide coenzyme, whhich is present in the solution, is reduced in the enzymatic reaction and is re-oxidized amperometrically at 0 mV vs. Ag/AgCl. The properties of such electrodes depend on whether the mediator or the enzyme is adsorbed first; possible models for the molecular arrangements at the surface are discussed. The modified electrode is mounted in a flow-through cell in a flow-injection system and tested with 50-μl injections of β-d-glucose. The calibration graphs were linear in the range 5 × 10^?6—2 × 10^?3 M βd glucose with the highest sensitivity at pH 6.0. The membrane-free enzyme electrode has a fast response; peak widths are 12 s at half height (flow rate 0.7 ml min^?1, making it possible to process 100 samples h^?1.     

A novel electrochemical noise sensor applied to detect food safety

A novel electrochemical noise (EN) sensor was elaborately designed to detect the metal residue in energy drinks. By calculating the characteristic parameter, noise resistance R _n, obtained from the EN data, the tin and iron residue can be semiquantitatively evaluated. In addition, R _n was further compared with the inductively coupled plasma mass spectrometer (ICP-MS) results. Accordingly, an interesting relationship was found between the EN data and ICP-MS results. The experimental results reveal that R _n can indirectly reflect the corrosion-induced metal release from the packaging materials; a lower R _n means a higher metal release. This electrochemical sensor has potential applications in evaluating food safety because of its fast, economic and in-situ features.     

A novel poly(cyanocobalamin) modified glassy carbon electrode as electrochemical sensor for voltammetric determination of peroxynitrite

This report described the direct voltammetric detection of peroxynitrite (ONOO⁻) at a novel cyanocobalamin modified glassy carbon electrode prepared by electropolymeriation method. The electrochemical behaviors of peroxynitrite at the modified electrode were studied by cyclic voltammetry. The results showed that this new electrochemical sensor exhibited an excellent electrocatalytic activity to oxidation of peroxynitrite. The mechanism of catalysis was discussed. Based on electrocatalytic oxidation of peroxynitrite at the poly(cyanocobalamin) modified electrode, peroxynitrite was sensitively detected by differential pulse voltammetry. Under optimum conditions, the anodic peak current was linear to concentration of peroxynitrite in the range of 2.0 × 10⁻⁶ to 3.0 × 10⁻⁴ mol L⁻¹ with a detection limit of 1.0 × 10⁻⁷ mol L⁻¹ (S/N of 3). The proposed method has been applied to determination of peroxynitrite in human serum with satisfactory results. This poly(cyanocobalamin) modified electrode showed high selectivity and sensitivity to peroxynitrite determination, which could be used in quantitative detection of peroxynitrite in vivo and in vitro.     

Ultrathin CuxO nanoflakes anchored Cu2O nanoarray for high-performance non-enzymatic glucose sensor

Journal of Solid State Electrochemistry - Designing highly active material to fabricate high-performance glucose sensor was great importance for diabetes treatment. In this work, we develop a novel...     

高性能多级花状Co3O4基无酶葡萄糖电化学传感器

以硝酸钴、碳酸钠、尿素为原料,泡沫镍为基体,采用水热和煅烧相结合的二步法制备了一种多级花状Co_3O_4/Ni异质结构的无酶葡萄糖传感器。通过X射线衍射与扫描电镜对Co_3O_4/Ni电极的成分及形貌进行了表征,并采用循环伏安法在1mol/L KOH溶液中测试了Co_3O_4/Ni异质结构葡萄糖传感器电极的电化学性能。结果表明,通过二步法在泡沫镍表面制备的Co_3O_4呈现多级花状纳米纤维结构。将制备的Co_3O_4/Ni异质结构作为电极构建的无酶葡萄糖传感器表现出响应时间快(低于5s)、检测灵敏度高(7.4m A·(mmol/L)~(-1)·cm~(-2))、检出限低(1.17μmol/L,S/N=3)和线性检测范围宽(0~5 mmol/L)的特点。进一步的抗干扰性检测表明所制备的传感器在+0.44V vs.SCE对葡萄糖表现出良好的选择性。本文所制备的多级花状Co_3O_4基电极在无酶葡萄糖传感器的发展中有着很大的应用潜力。     

Sensitive determination of herbicide trifluralin on the surface of copper nanowire electrochemical sensor

A novel voltammetric method for the determination of trifluralin is proposed based on a composit of carbon paste and copper nanowire as a sensitive sensor. The presence of copper nanowire in the composite film enhance the conductivity and as a result increased the electron transfer rate constant and so the current will increase. The composite exhibits a promising higher electrocatalytic activity towards the oxidation of trifluralin in pH 4.0 aqueous solution. The reduction peak currents of trifluralin increased remarkably and the reduction peak potential shifted positively at the nanostructuring electrode, compared with that at a bare CPE which show the enhanced effect of nanowire. The support electrolyte to provide a more defined and intense peak current for trifluraline determination was 0.05 mol L⁻¹ phosphate buffer at pH 4.0. The fast Fourier transform square wave voltammetry was used as a new electrochemical technique in flow injection system to abtain more sensitivity by application of discrete fast Fourier transform method by background subtraction and two-dimensional integration of the electrode response over a selected potential range and time window, the signal-to-noise ratio has significantly increased and made the sensivity to be higher than other methods. The effective parameters such as frequency, amplitude, and pH were optimized to get the best sensitivity. As a result, the sensor showed a valuable response in linear concentration range of 100–0.02 nmol L⁻¹ with a (limit of detection) LOD of 0.008 nmol L⁻¹ and (limit of quantification) LOQ of 0.15 nmol L⁻¹ for trifluralin. A good recovery was obtained for assay spiked urine samples and a good quantification of trifluralin was achieved in soil samples.     

Facile one-step electrochemical fabrication of a non-enzymatic glucose-selective glassy carbon electrode modified with copper nanoparticles and graphene

We have developed a non-enzymatic glucose sensor by using a composite prepared from copper nanoparticles (CuNPs) and graphene which can be prepared by simple 1-step electrochemical reduction using graphene oxide (GO) and copper ion as the starting materials. The GO is electrochemically reduced to graphene at a voltage of ?1.5 V, and this is accompanied by the simultaneous formation of CuNPs on the surface of the graphene. This novel nanocomposite combines the advantages of graphene and of CuNPs and displays good electrocatalytic activity toward glucose in alkaline media. The performance of the respective glucose electrode was evaluated by amperometric experiments and revealed a fast response (<2 s), a low detection limit (200 nM), and high sensitivity (607 μA mM^?1). The sensor also exhibits good reproducibility and very good specificity for glucose over ascorbic acid, dopamine, uric acid, fructose, lactose and sucrose.

ZnO/石墨烯修饰电极的制备及电化学性能研究

采用水热法合成了纳米氧化锌-氧化石墨烯复合材料,并基于该复合材料构制了一种新型双酚A传感器,研究了该传感器的电化学行为。结果表明,在含8.0×10-5mol/L CTAB的p H 7.0磷酸盐缓冲液中,双酚A在0.573V处出现1个不可逆的氧化峰,具有良好的电化学响应;其氧化峰电流与浓度在1.0×10-8~4.0×10-5mol/L范围内呈良好的线性关系,检出限为5.0×10-9mol/L;对模拟环境水样中双酚A进行3次平行测定的回收率在96.3%~101.9%之间,相对误差在1.2%~3.8%范围内。该传感器具有灵敏度高、线性范围宽的特点。