利用Cu0/多壁碳纳米管纳米复合物修饰玻碳电极快速非酶法检测葡萄糖和果糖(英文)

A nonenzymatic electrochemical sensor for glucose and fructose was fabricated that contained a glassy carbon electrode modified with a copper oxide (CuO)/multiwalled carbon nanotube (MWCNT) nanocomposite. The electrochemical properties of the CuO/MWCNT‐modified glassy carbon electrode were investigated. Two distinguishable anodic peaks were observed around 0.30 and 0.44 V corresponding to the oxidation of glucose and fructose, respectively, at the surface of the modified electrode. The detection limits for glucose and fructose were both 0.04 mmol/L. The sensor was used to simultaneously determine the concentrations of glucose and fructose in hydrolyzed sucrose samples, and to measure glucose in blood serum samples, demonstrating its potential as a nonenzymatic carbohydrate sensor.     

A nonenzyme glucose sensor based on Cu/Ni/CMWCNTs nanocompositesEI北大核心CSCD

Copper-nickel bimetallic nanoparticles decorated on carboxylated multi-walled carbon nanotubes （Cu/Ni/CMWCNTs）were prepared by using a simple one-pot solvothermal method,which was then employed to construct a highly sensitive non-enzymatic glucose sensor. The modified electrode showed high sensitivity and stability in glucose detection,which was mainly attributed to the synergistic effect of the compact copper-nickel nanocomposite and carboxylated multi-walled carbon nanotubes that possessing high specific surface area to increase the number of active sites and to improve the electrocatalytic activity of the modified electrode. The phase structure and morphology of the material were characterized by X-ray diffraction and scanning electron microscope; the electrochemical performance of the sensor was studied by cyclic voltammetry and chronoamperometry. The sensor had a sensitivity of 1949.1 μµA·L/（mmol·cm2）for glucose detection in the linear range of 1.0-8000 μµmol/L at a potential of 0.55 V,and the detection limit was 0.2 μµmol/L. The sensor was also applied to measure the concentration of glucose in serum samples. The developed nanocomposites sensor has the potential prospect to monitor blood glucose. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

氧化钴和氮掺杂碳纳米管纳米复合物的催化与容量性质(英文)

The nanocomposites based on cobalt oxide and nitrogen-doped carbon nanofibers (N-CNFs) with cobalt oxide contents of 10–90 wt% were examined as catalysts in the CO oxidation and supercapacity electrodes. Depending on Со3О4 content, such nanocomposites have different morphologies of cobalt oxide nanoparticles, distributions over the bulk, and ratios of Со3+/Co2+ cations. The 90%Со3О4-N-CNFs nanocomposite showed the best activity because of the increased concentration of defects in N-CNFs. The capacitance of electrodes containing 10%Со3О4-N-CNFs was 95 F/g, which is 1.7 times higher than electrodes made from N-CNFs.     

Rapid detection of chlorpheniramine maleate by an electrochemical sensor based on metal-organic frameworks CHP@Cu3（BTC）2 /MWCNTsEI北大核心CSCD

Copper hydroxyphosphate@metal-organic frameworks/multi-wall carbon nanotube composites （CHP@Cu3 （BTC）2 /MWCNTs）were prepared by a new in-situ template method and then an electrochemical sensor was developed based on the composites. The crystal structure and morphology of the material were characterized by X-ray diffraction and scanning electron microscope. Cyclic voltammetry and linear sweep voltammetry were used to study the electrochemical catalytic performance，and the determination conditions were optimized. The rapid and sensitive detection of chlorphenamine maleate was realized. There was a good linear relationship between the oxidation peak current and concentration of chlorphenamine maleate in the ranges from 5 to 100 µμmol/L and from 150 to 800 µμmol/L，and the linear equations were as Ipa （µμA）=0.1559c（µμmol/L）-0.3533 （R2 =0.9973）and Ipa （µμA）=0.02328c（µμmol/L）+16.63（R2 =0.9594），and the detection limit was 1.67 µμmol/L. The recoveries of the actual drug ranged from 91.0% to 109.1%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Studies on PNPP Hydrolysis Catalyzed by Schiff Base Cobalt（Ⅱ） Complexes

Two cobalt（Ⅱ） complexes of the Schiff base with morpholino or aza-crown ether pendants, CoL^1 and CoL^2, as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester （PNPP）. The analysis of specific absorption spectra of the hydrolytic reaction systems indicates that key intermediates, made up of PNPP and Co（Ⅱ） complexes, have been formed in reaction processes of the PNPP catalytic hydrolysis. The mechanism of PNPP catalytic hydrolysis has been proposed based on the analytic result of specific absorption spectrum. A kinetic mathematical model, applied to the calculation of the kinetic parameter of PNPP catalytic hydrolysis, has been established based on the mechanism proposed. The acid effect of buffer solution, structural effect of the complexes, and effect of temperature on the rate of PNPP hydrolysis catalyzed by the complexes have been also discussed.     

Pd nanoparticles on boron doped graphene catalyst for electrochemical detection of hydrogen peroxide prepared by electroless deposition methodEI北大核心CSCD

Taking advantage of large conjugated structure and reductivity of boron-doped graphenethe palladium nanoparticles/boron-doped graphene catalyst was prepared by electroless deposition method using boron-doped graphene as reductant and stabilizer. The average size of palladium nanoparticles highly dispersed on the surface of boron-doped graphene was about 6.5 nm. The electrochemical sensor was prepared by modifying the as-formed catalyst on the surface of glassy carbon electrode. The obtained electrochemical sensor exhibited an excellent electrochemical catalytic activity for H2 O2 . It exhibited high sensitivity with the detection limit as low as 830 nmol/L and good linearity in the range of 2.5-300 μµmol/L for detection of H2 O2 . It could be utilized for the determination of H2 O2 in milk samples. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

Amorphous Cu0 on Carbon Nanofiber as Recyclable Heterogeneous Catalyst for N-Arylation Reactions

A novel heterogeneous catalyst,amorphous Cu^0 on the carbon nanofibers was developed and characte-rized by means of several characterization techniques.The prepared Cu^0 was investigated as a heterogeneous catalyst for N-arylation reaction.The results show it is an excellent catalyst with recyclability,high consistency and catalytic activity.After the catalyst was used for 5 cycles in the N-arylation reaction,amorphous Cu^0 reunited into crystalline copper nanoparticles with different particle sizes and its good heterogeneity in the catalytic system was confirmed after the catalyst recovery.     

Highly Selective Salicylate Membrane Electrode Based on N,N＇- （Aminoethyl）ethylenediamide Bis（2-salicylideneimine） Binuclear Copper（Ⅱ） Complex as Neutral Carrier

A new ion selective electrode for salicylate based on N,N＇-（aminoethyl）ethylenediamide bis（2-salicylideneimine） binuclear copper（Ⅱ） complex [Cu（Ⅱ）2-AEBS] as an ionophore was developed. The electrode has a linear range from 1.0 × 10^-1 to 5.0 ×10^-7 mol·L^- 1 with a near-Nemstian slope of （ - 55 ±1 ） mV/decade and a detection limit of 2.0 × 10-7 mol·L^-1 in phosphorate buffer solution of pH 5.0 at 25 ℃. It shows good selectivity for Sal^- and displays anti-Hofmeister selectivity sequence： Sal^-〉SCN^-〉 ClO4^- 〉I^-〉 NO2^- 〉Br^-〉 NO3^- 〉Cl^-〉 SO3^2- 〉 SO4^2- The proposed sensor based on binuclear copper（Ⅱ）complex has a fast response time of 5-10 s and can be used for at least 2 months without any major deviation. The response mechanism is discussed in view of the alternating current （AC） impedance technique and the UV-vis spectroscopy technique. The effect of the electrode membrane compositions and the experimental conditions were studied. The electrode has been successfully used for the determination of salicylate ion in drug pharmaceutical preparations.     

Determination of Pb(II) and Cu(II) by Electrothermal Atomic Absorption Spectrometry after Preconcentration by a Schiff Base Adsorbed on Surfactant Coated Alumina

1,2-Bis（salicylidenamino）ethane loaded onto sodium dodecyl sulfate-coated alumina was used as a new chelating sorbent for the preconcentration of traces of Pb（Ⅱ） and Cu（Ⅱ） prior to atomic absorption spectrometric determination. The influence of pH, flow rates of sample and eluent solutions, and foreign ions on the recovery of Pb（Ⅱ） and Cu（Ⅱ） by this sorbent has been studied. The retained ions were eluted with 4 mol·L nitric acid and determined by electrothermal atomic absorption spectrometry （ETAAS）. The data of limit of detection （3σ） for Pb（Ⅱ） and Cu（Ⅱ） were found to be 8.57 and 2.69 ng·L^-1 respectively, while the enrichment factor for both ions was 100. The proposed method was successfully applied to determination of lead and copper in different water samples.     

Colorimetric detection of glucose using a boronic acid derivative receptor attached to unmodifed AuNPs简

A simple, cheap and non-enzymatic colorimetric strategy for glucose detection has been designed based on the interactions between a phenylboronic acid （PBA） derivative, which is coupled with gold nanoparticles （AuNPs） as the colorimetric reporters, and glucose. The PBA-AuNPs hybrid system proposed here exhibits ordered photochemistry behaviors upon the addition of glucose at different pH values. There are two linear regions of glucose concentration for the glucose sensor at different pH values, i.e., between 0.1 mmol/L and 9.8 mmol/L at pH 6 with the detection limit of 64μmol/L and between 0 and 6.5 mmol/L with the detection limit of 48 μmol/L at pH 9, respectively. To test the practicality of the sensor system, we also applied this assay to detect a glucose sample in the artificial saliva.     

MOF derived Co3O4/N-doped carbon nanotubes hybrids as efficient catalysts for sensitive detection of H2O2 and glucose

Developing enzyme-free sensors with high sensitivity and selectivity for H2O2 and glucose is highly desirable for biological science.Especially,it is attractive to exploit noble-metal-free nanomaterials with large surface area and good conductivity as highly active and selective catalysts for molecular detection in enzyme-free sensors.Herein,we successfully fabricate hollow frameworks of Co3O4/N-doped carbon nanotubes(Co3O4/NCNTs)hybrids by the pyrolysis of metal-organic frameworks followed by calcination in the air.The as-prepared novel hollow Co3O4/NCNTs hybrids exhibit excellent electrochemical performance for H2O2 reduction in neutral solutions and glucose oxidation in alkaline solutions.As sensor electrode,the Co3O4/NCNTs show excellent non-enzymatic sensing ability towards H2O2 response with a sensitivity of 87.40μA(mmol/L)^-1 cm^-2,a linear range of 5.00μmol/L-11.00 mmol/L,and a detection limitation of 1μmol/L in H2O2 detection,and a good glucose detection performance with 5μmol/L.These excellent electrochemical performances endow the hollow Co3O4/NCNTs as promising alternative to enzymes in the biological applications.     

MOF-derived Cu_2O/Cu NPs on N-doped Porous Carbon as a Multifunctional Sensor for Mercury(Ⅱ) and Glucose with Wide Detection Range

Cu_2O/Cu nanoparticles(NPs) in the nanoporous carbon matrix(designated as Cu_2O/Cu@NPC) has been synthesized by in-situ calcination of a cupper-based metal-organic framework(Cu-MOF), and its morphology and composition were characterized by PXRD, SEM and Raman. Furthermore, elemental mapping and XPS analysis not only show Cu NPs is generated along with nitrogen(N)-doped carbon, but also indicate Cu_2O NPs locates in the external layer of Cu@NPC. In addition, the adsorption of dye studies implies that Cu_2O/Cu@NPC exhibits obvious interaction with Rhodamine B(Rh B) due to the feature of porous and N-doped structure. Cu_2O/Cu@NPC has highly electrocatalytic performance for glucose and mercury(Ⅱ) with wide detection range and good stability, which can be used as a novel multifunctional sensor for glucose and mercury(Ⅱ).     

四氮大环-金属配合物与DNA作用的电化学及谱学研究

Mononuclear copper（Ⅱ）, nickel（Ⅱ） and cobalt（Ⅲ） tetracoordinate macrocyclic complexes were synthesized and spectroscopically characterized. The crystal structure of the three compounds were determined by X-ray crystallography. The electrochemical experimental results indicate that the three complexes could interact with DNA mainly by electrostatic interaction. The interaction of tetracoordinate macrocyclic cobalt（Ⅲ） complex with DNA was studied by cyclic voltammetry and UV-vis spectroscopy. The experimental results reveal that tetracoordinate macrocyc- lic cobalt（Ⅲ） complex could interact with DNA by electrostatic interaction to form a 1 ： 1 DNA association complex with a binding constant of 7.50 ×10^3 L·mol^-1.     

Preparation and application of novel polymer nanoparticles in the detection of copper ion and cysteineEI北大核心CSCD

A novel amphiphilic copolymer,dipropenoxystyrene anthracene and acrylic acid copolymer（BASA-AA） was designed and synthesized based on divinyl anthracene. The polymer self-assembled rapidly in water to create polymer nanoparticles（BASA-AA NPs）with a uniform size of 45 nm,no dye leakage,and great brightness（Φ= 36%）. Because of the enormous number of carboxyl groups on the surface of the particles,it can disperse extremely well in water,and can be used for the rapid detection of copper ion and cysteine（Cys）in pure water, with the limit of detection of 45 nmol/L. The fluorescent intensity of the nanoparticles will be greatly reduced after the introduction of copper ion,realizing the detection of copper ion with high selectivity and sensitivity. A composite probe made of BASA-AA NPs and copper ion can detect Cys in the range of 0.1-10 µμmol/L,with the detection limit of 84 nmol/L,due to the high binding capacity of the sulfhydryl group and copper ion. The method is simple and rapid in material synthesis and preparation,and shows high selectivity and sensitivity in pure water. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Electrospun CoSe@N-doped carbon nanofibers with highly capacitive Li storage

One-dimensional nano-structured materials have attracted attention due to its unique properties afforded such as the across-linked structures and large aspect ratios.In this work,one-dimensional CoSe@N-doped carbon nanofibers(CoSe@NCNFs)are successfully by combining the techniques of electrospinning and annealing.Selenium powder are directly dispersed in the polyacrylonitrile/N,N-Dimethylformamide(DMF)solution containing cobalt salt to form the product.The performance of these materials was investigated in Li-ion batteries after the annealing at different temperatures.The Co Se@NC nanofibers annealed at 550℃(CoSe@NC-550)and displayed excellent storage properties,affording a high capacity of 796 m Ah·g~(-1)at a current density of 1 A·g~(-1)for 100 cycles.Moreover,it is confirmed that the pseudocapacitive contribution of CoSe@NC-550 is up to 72.8%at the scan rate of 1 mV/s through the cyclic voltammetry analysis.     

Dimerization of Propylene by Nickel (Ⅱ) and Cobalt (Ⅱ) Catalysts Based on Bidentate Nitrogen-phosphino Chelating Ligands

The catalytic property of propylene dimerization by several nickel (Ⅱ), cobalt (Ⅱ) complexes containing N-P bidentate ligands was studied in combination with organoaluminum co-catalysts. The effects of the type of aluminum co-catalysts and its relative amount, the nature of precursors in terms of ligand backbone and metal center were investigated. The results indicated that precursor I (N,N-dimethyl-2-(diphenylphosphino)aniline nickel (Ⅱ) dichloride) exhibited high activity in propylene dimerization in the presence of the strong Lewis acid Et3Al2Cl3, whereas low productivity by its cobalt analogues was observed under identical reaction conditions.     

Sensing nanomaterials of wearable glucose sensors

The metabolic disorder of glucose in human body will cause diseases such as diabetes and hyperglycemia.Hence the determination of glucose content is very important in clinic diagnosing.In recent years,researchers have proposed various non-invasive wearable sensors for rapid and real-time glucose monitoring from human body fluids.Unlike those reviews which discussed performances,detection environments or substrates of the wearable glucose sensor,this review focuses on the sensing nanomaterials since they are the key elements of most wearable glucose sensors.The sensing nanomaterials such as carbon,metals,and conductive polymers are summarized in detail.And also the structural characteristics of different sensing nanomaterials and the corresponding wearable glucose sensors are highlighted.Finally,we prospect the future development requirements of sensing nanomaterials for wearable glucose sensors.This review would give some insights to the further development of wearable glucose sensors and the modern medical treatment.     

铜锌超氧化物歧化酶与丝氨酸钴(Ⅱ)的相互作用

The effect of changing the amount of externally added cobalt(Ⅱ) serine, an organic metal compound, and the pH value of the enzyme solution on the interaction of copper zinc superoxide dismutase (Cu 2Zn 2SOD) with cobalt(Ⅱ) serine was studied by means of visible spectroscopy, inductively coupled plasma atomic emission spectrometry and measurement of enzyme activity. It was found that in aqueous solution, there exists a direct interaction of the metal ions of the active center in Cu 2Zn 2SOD with cobalt(Ⅱ) serine. As a result, part of the metal ions in the metalloenzyme were replaced by Co ion to form Co(Ⅱ) substituted derivatives of SOD and the catalytic activity of the enzyme decreased.     

Gold Nanoparticle-based Colorimetric Assay for Determination of Lead(Ⅱ) in Aqueous Media

The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead(Ⅱ) ion(Pb2+).Pentapeptide,cysteine-alanine-leacine-asparagine-asparagine(CALNN),functionalized gold nanoparticles(GNPs) were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process,which caused an easily measurable change in the absorption spectrum of the particles.Typically,mono-dispersing GNPs exhibit an absorption band at 522 nm,corresponding to a red color solution,while aggregated GNPs have it at longer wavelengths,corresponding to a purple or blue color solution.The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA.Highly selective and sensitive detection of Pb2+ in aqueous solution is thus provided.A detection limit of 0.1 μmol/L of Pb2+ was demonstrated.