查找使用阿拉丁产品的科研文献

Monolithically integrated copper phosphide nanowire: An efficient electrocatalyst for sensitive and selective nonenzymatic glucose detection

Lisi Xie,Abdullah M. Asiri,Xuping Sun

The detection of glucose plays a significant role in diagnostics and management of diabetes and it is thus desired to develop non-noble-metal electrocatalyst for nonenzymatic glucose sensing. This work demonstrates the first use of monolithically integrated copper phosphide nanowire on copper foam (Cu 3 P NW/CF) as an efficient catalyst for electrochemical oxidation of glucose. As a nonenzymatic glucose sensor , this Cu 3 P NW/CF exhibits a low detection limit of 0.32   μM at a signal-to-noise ratio of 3 with a linear range from 0.005 to 1   mM (R 2   =   0.997). It also shows high anti-interference property to other normally co-existing electroactive species including lactose, fructose, ascorbic acid , uric acid , urea, dopiamine, and sucorse as well as excellent resistance to chloride poisoning. Its application for glucose detection in human serum sample is also demonstrated successfully.

Synthesis of PtxSn/MWCNTs and their Application in Non-enzymatic Glucose and Hydrogen Peroxide Sensors

Hui Min,Wenqin Wu,Huimin Wu,Shengfu Wang,Chuanqi Feng,Yu Ding

Pt x Sn/MWCNTs (x=1, 2, 3) nanocomposites were synthesized by chemical reduction. Comparing all of the materials, the results revealed that the best material was Pt 3 Sn/MWCNTs. The sensor based on Pt 3 Sn/MWCNTs exhibited excellent catalytic activities towards glucose and hydrogen peroxide. Sensing of glucose had a double-linear range: one was between 50 μM and 550 μM, the other was between 1.35 mM and 16.35 mM. These were due to the fact that more and more intermediate species were adsorbed onto the electrode surface with increasing concentration of glucose, which limited the following glucose oxidation. Meanwhile, the sensor also had a linear response range between 0.05 mM and 18.95 mM for hydrogen peroxide. Furthermore, the glucose and hydrogen peroxide sensors exhibited excellent selectivity, stability, and reproducibility. Thus the sensors had potential utilities in the detection of glucose and hydrogen peroxide.

A novel electrochemical aptasensor for ultrasensitive detection of kanamycin based on MWCNTs–HMIMPF6 and nanoporous PtTi alloy

Wenjuan Guo,Na Sun,Xiaoli Qin,Meishan Pei,Luyan Wang

A novel aptasensor based on a novel composite film consisting of multi-walled carbon nanotubes (MWCNTs), ionic liquid (IL) of 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF 6 ), and nanoporous PtTi (NP-PtTi) alloy was constructed for ultrasensitive detection of kanamycin . The NP-PtTi alloy was successfully fabricated by a simple dealloying of PtTiAl source alloy in HCl solution. The NP-PtTi alloy has uniform interconnected network structure with specific surface area and was used to immobilize aptamer. After modified with the composite material, current signal was amplified obviously, which attributed to the larger specific surface area and excellent electrical conductivity of NP-PtTi and MWCNTs. A number of factors affecting the activity of the aptasensor have been discussed and optimized. Under the optimized conditions, the proposed aptasensor provided a linear range of 0.05–100   ng   mL −1 with a low detection limit of 3.7   pg   mL −1 . This aptasensor displayed high sensitivity, stability and reproducibility. In addition, the as-prepared aptasensor was successfully used for the determination of kanamycin in a real sample.

Nickel nanoparticles modified conducting polymer composite of reduced graphene oxide doped poly(3,4-ethylenedioxythiophene) for enhanced nonenzymatic glucose sensing

Ni Hui,Shiying Wang,Hongbo Xie,Shenghao Xu,Shuyan Niu,Xiliang Luo

A facile two-step electrochemical strategy was reported to synthesize nanocomposite of reduced graphene oxide (RGO) doped conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) decorated with nickel nanoparticles (NiNPs) onto a glassy carbon electrode (GCE). Pure graphene oxide (GO) doped PEDOT composite was firstly electropolymerized onto the GCE through cyclic voltammetry, followed by electrochemical reduction in a solution containing nickel cations at a constant potential of −0.9   V. During the electrochemical reduction process, GO doped in the PEDOT composite would be reduced to a more conductive form of RGO, and at the same time, nickel cations could be reduced to form NiNPs and loaded on the composite surface. The prepared nanocomposite (NiNPs/PEDOT/RGO) modified electrode showed outstanding electrocatalytic activity toward the oxidation of glucose in alkaline media, and it could be developed into a nonenzymatic glucose sensor. Under optimum conditions, the glucose sensor exhibited a linear range from 1.0   μM to 5.1   mM and a detection limit of 0.8   μM (S/N   =   3), associated with excellent stability, high reproducibility and favorable selectivity against common interferents. Furthermore, the nonenzymatic sensor was also successfully applied to the detection of glucose in human serum samples, showing promising potential in the clinical application.

A high-performance nonenzymatic piezoelectric sensor based on molecularly imprinted transparent TiO2 film for detection of urea

Zheng-peng Yang,Xuan Liu,Chun-jing Zhang,Bao-zhong Liu

Transparent photocatalytic surfaces are of ever increasing importance for the enhancement of the photocatalytic efficiency. Here, the highly ordered transparent TiO 2 nanotube arrays were prepared by the anodization and thermal annealing of titanium layer deposited onto the glass substrate , and a novel nonenzymatic piezoelectric sensor was developed for urea detection based on the modification of molecularly imprinted TiO 2 thin film onto transparent TiO 2 nanotube arrays. The performance of the fabricated sensor was evaluated and the results indicated that the sensor exhibited high sensitivity in urea detection, with a linear range from 0.04 to 120   μM and a limit of detection of 0.01   μM. Moreover, the sensor presented outstanding selectivity while used in coexisting systems containing various interferents with high concentration. The analytical application of the urea sensor confirmed the feasibility of urea detection in urine sample.

Novel water-soluble multi-nanopore graphene modified glassy carbon electrode for simultaneous determination of dopamine and uric acid in the presence of ascorbic acid

Xiaohua Zhu,Yong Liang,Xiaoxi Zuo,Ruiping Hu,Xin Xiao,Junmin Nan

A novel graphene-based nanomaterial , multi-nanopore graphene (mp-GR), modified glassy carbon electrode (mp-GR/GCE) is prepared for the simultaneous determination of dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA). After a hydrothermal reaction of the graphene oxide in the presence of H 2 O 2 at 180   °C for 2   h, the water-soluble mp-GR is obtained from the hydrothermal suspension. This mp-GR exhibits abundant carboxylic and/or hydroxide groups, edges, and defective sites due to the reaction and structure disruption caused by the hydrothermal treatment . The mp-GR appears an enhanced electrocatalytic activity toward DA and UA due to the unique structure and composition . The oxidation peak current of DA at the mp-GR/GCE is about 2.70 and 8.61 times higher than at the GR/GCE and the GCE, respectively. Using the mp-GR/GCE, the simultaneous differential pulse voltammetry determination of DA and UA in the presence of AA is successfully carried out, the detection limits (S/N   =   3) for DA and UA are 1.5   ×   10 −6   mol   L −1 and 2.0   ×   10 −6   mol   L −1 , respectively. In addition, this mp-GR/GCE exhibits high selectivity, reproducibility, and stability, and also can detect DA and UA in real human blood serum, showing its promising application in the electroanalysis of real samples.

Simultaneous determination of ascorbic acid, dopamine, and uric acid based on double-walled carbon nanotubes/choline-modified electrode

Bingbing Xu,Qijun Song,Haijun Wang

A novel protocol for simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA) based on double-walled carbon nanotubes (DWNTs)/choline (Ch) modified glassy carbon electrode (GCE) was presented. Ch was covalently immobilized on the GCE through oxygen atoms. The Ch monolayer provides a positively charged monolayer, which could attract negatively charged DWNTs through electrostatic interaction. In the simultaneous determination of aforementioned three analytes using CV, the electrochemical signals were well separated into three oxidation peaks with peak potential differences of 0.182 V (AA–DA), 0.146 V (DA–UA) and 0.328 V (AA–UA). In amperometric studies of AA, DA and UA, the modified electrode exhibited wide linear ranges of 0.10–777 μM, 0.06–314 μM and 0.25–344 μM and low detection limits of 0.03, 0.03, and 0.05 μM, respectively. Amperometric responses of AA, DA and UA were within 1 s. Moreover, this modified electrode was further applied to determine AA, DA and UA in real samples with satisfactory results.

Application of NaYF4:Yb,Er Nanoparticles as Peroxidase Mimetics in Uric Acid Detection

Yu-Rong TANG,Yu ZHANG,Rui LIU,Ying-Ying SU,Yi LÜ

The poly(acrylic acid) functionalized NaYF 4 :Yb,Er nanoparticles (NPs) were found to possess intrinsic peroxidase-like activity, which could catalyze oxidization of 3,3′,5,5′-tetramethylbiphenyl (TMB) by H 2 O 2 to produce a color variation. Using TMB as substrate, we systematically studied the effect of a series of conditions, such as temperature and pH, on the catalytic activity of NaYF 4 :Yb,Er NPs. When combined with uricase, the proposed colorimetric method could be successfully used for the determination of uric acid. Under the optimum conditions, the linear range of this method was from 1.0 × 10 −5 M to 2.0 × 10 −4 M with the detection limit down to 5.3 × 10 −6 M. Moreover, the developed method was applied to detect uric acid in serum samples and the results were in good agreement with those reported by the hospital.

Amperometric sensor based on tricobalt tetroxide nanoparticles–graphene nanocomposite film modified glassy carbon electrode for determination of tyrosine

Lin Jiang,Shuqing Gu,Yaping Ding,Daixin Ye,Zhen Zhang,Fenfen Zhang

An electrochemical sensor based on tricobalt tetroxide nanoparticles–graphene nanocomposite film modified glassy carbon electrodes (GCEs) for sensitive determination of l -tyrosine (L-Tyr) was presented here. The nanoparticles were fabricated by electro-polymerization technology. Scanning electron microscopy was implemented to characterize morphology of the nanocomposite film. The electron transfer behavior of modified electrodes was investigated in 5   mM   K 3 [Fe(CN) 6 ]/K 4 [Fe(CN) 6 ] solution using cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The electrochemical response of modified electrodes toward L-Tyr was investigated by cyclic voltammetry (CV), square wave voltammetry (SWV), amperometry in detail. The results indicated that synergistic effect of Co 3 O 4 NPs and graphene film dramatically improved the conductivity and sensitivity of the sensor. Under optimal conditions, a wide linear relationship between the responses and L-Tyr concentrations ranging from 1.0   ×   10 −8 to 4.0   ×   10 −5   mol   L −1 was obtained with a comparatively low detection limit of 1.0   ×   10 −9   mol   L −1 . Furthermore, the sensor also displays excellent sensitivity and high stability. To further study the practical applicability of the fabricated sensor, it was applied to detect real samples and the received results were satisfactory.

Direct electron transfer glucose biosensor based on glucose oxidase self-assembled on electrochemically reduced carboxyl graphene

Bo Liang,Lu Fang,Guang Yang,Yichuan Hu,Xishan Guo,Xuesong Ye

A glucose biosensor based on direct electron transfer of glucose oxidase (GOD) self-assembled on the surface of the electrochemically reduced carboxyl graphene (ERCGr) modified glassy carbon electrode has been reported. X-ray photoelectron spectroscopy (XPS) analyses of ERCGr indicate most of the oxygen-containing groups such as epoxy/ether groups and hydroxyl groups in the carboxyl graphene were eliminated, while carboxylic acid groups remained. GOD was immobilized on the ERCGr modified glassy carbon electrode via self-assembly. The cyclic voltammetric result of the electrode shows a pair of well-defined and quasi-reversible redox peaks with a formal potential of −0.467   V and a peak to peak separation of 49   mV, revealing that the direct electron transfer between GOD and the electrode has been achieved. The proposed biosensor exhibits a linear response to glucose concentrations ranging from 2 to 18   mM with a detection limit of 0.02   mM. Moreover, this facile, fast, environment-friendly and economical preparation strategy of ERCGr may be extended for the preparation of other graphene based enzyme electrode biosensors.

Uricase-Based Highly Sensitive and Selective Spectrophotometric Determination of Uric Acid Using BSA-Stabilized Au Nanoclusters as Artificial Enzyme

Huihui Zhao,Zhonghui Wang,Xue Jiao,Lichun Zhang,Yi Lv

Nonenzymatic electrochemical sensor based on Fe@Pt core–shell nanoparticles for hydrogen peroxide, glucose and formaldehyde

He Mei,Wenqin Wu,Beibei Yu,Huimin Wu,Shengfu Wang,Qinghua Xia

Fe@Pt core–shell nanoparticles were synthetized by spontaneous replacement reaction, using Vulcan XC-72 carbon as support. The physical properties of the obtained Fe@Pt/C nanocomposites were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy, and the electrocatalytic performances of the Fe@Pt/C were evaluated by cyclic voltammetry and chronoamperometry . Compared with the Pt/C, the Fe@Pt/C exhibited preferable electrocatalytic activity towards the reduction of hydrogen peroxide, and the oxidation of glucose and formaldehyde. Amperometric sensing of hydrogen peroxide was linear to its concentration in the range from 2.5   μM to 41.605   mM, with a detection limit of 750   nM (S/N   =   3) and a sensitivity of 218.97   μA mM −1 cm −2 . At the same time, the sensor based on Fe@Pt/C showed a linear response range of 1–16   mM glucose, and of 12.5   μM–15.4   mM formaldehyde, with high sensitivities of 11.75   μA mM −1 cm −2 and 40.18   μA mM −1 cm −2 , respectively.