铜簇修饰微电极小型硝酸根电化学检测系统（英文）

研制了一种用于硝酸根检测的小型电化学测量系统。该系统利用由微机电系统(MEMS)技术制备在玻璃基底上的铜簇修饰工作电极(WE)和铂对电极(CE),实现对水中硝酸根离子的浓度检测。设计了一个低噪声、高精度的恒电位仪模块来实现工作电极表面铜层的自更新、线性扫描电压的产生以及μA~mA级响应电流的检测。应用STM32F407微控制器控制测量过程并将检测结果显示在电容触摸屏上。实验结果表明,在0~71.4μmol·L-1浓度范围内,系统对硝酸根的检测具有较好的线性度(0.996)。与电化学工作站的检测结果进行对比,该小型系统表现出良好的性能。     

铜修饰微电极阵列硝酸根检测

许多水域含有过量的硝酸根,会诱发许多问题。采用微机电系统工艺,制备出一种基于铂叉指微电极阵列的硝酸根子（NO-3）检测微传感电极。通过电化学恒电位沉积法在铂叉指微电极阵列上修饰,得到多孔、簇状铜敏感膜。采用线性扫描伏安电化学检测方法,考察该微传感电极对NO-3的响应性能,在0~2 mg/L浓度范围内,线性度为0.999,灵敏度为-3.15 ALmg-1。在相同沉积修饰条件下,叉指微电极比同等敏感面积（1 mm2）的圆盘微电极表现出更强的催化活性和更高的灵敏度,分析其原因,认为主要是叉指微电极的结构和边缘效应造成的。     

铜修饰微电极阵列硝酸根检测（英文）

许多水域含有过量的硝酸根,会诱发许多问题。采用微机电系统工艺,制备出一种基于铂叉指微电极阵列的硝酸根离子(NO-3)检测微传感电极。通过电化学恒电位沉积法在铂叉指微电极阵列上修饰,得到多孔、簇状铜敏感膜。采用线性扫描伏安电化学检测方法,考察该微传感电极对NO-3的响应性能,在0~2mg/L浓度范围内,线性度为0.999,灵敏度为-3.15μA·L·mg-1。在相同沉积修饰条件下,叉指微电极比同等敏感面积(1mm2)的圆盘微电极表现出更强的催化活性和更高的灵敏度,分析其原因,认为主要是叉指微电极的结构和边缘效应造成的。     

紫外可见分光光度法测定铜及铜合金抛光液中的硝酸根

研究了紫外可见分光光度计在301.7 nm处测定铜及铜合金抛光液中硝酸根的浓度.方法的线性范围为0.9662-9.6621 g/L,适合于该类型抛光液中硝酸根的检测.该方法快速简便、准确度高、精密度好.     

基于片上系统协同计算的实时数据自动检测电化学传感器

针对应用于生物体内特征物质检测与跟踪的电化学传感器的其智能化和集成化问题,本文提出了一种基于片上系统的支持实时数据自动检测的电化学传感器。首先,将应用于电化学传感器结构,通过将测量样品、检测溶液接口、多电极和检测传导器等单元集成在片上系统,结合信号转换和电源装置,实现电化学传感器的独立计算、存储和通信功能。接着,通过实现待测量物多电极、检测溶液电极子和单片机逻辑控制的协同计算满足自动检测需求。最后,基于数据整合与自动化处理设计了支持实时数据检测的电化学传感器。验证结果表明,在数据检测精度和实时性方面所提方案明显优于传统的非片上系统电化学传感器。     

超氧化物歧化酶在L—半胱氨酸修饰金电极上电化学行为的现场拉曼 …

在以电化学方法确认Ｌ－半胱氨酸对铜－锌超氧化物歧化酶（ｃｏｐｐｅｒ,ｚｉｎｃ ｓｕｐｅｒｏｘｉｄｅ ｄｉｓ－ｍｕｔａｓｅ,ＳＯＤ）在金丝电极上的电子迁移过程起促进作用的基础上,本文论述了将拉曼光谱电化学方法应用于猪红细胞ＳＯＤ在经Ｌ－半胱氨酸修饰的金丝电极上的金电极上的电化学行为的现场拉曼光谱研究。研究结果从分子水平上提供了有关Ｌ－半胱氨酸修饰在金电极上的电化学过程中,以及ＳＯＤ在Ｌ－半胱氨酸修饰     

CdSe/ZnS电化学发光法测定去甲肾上腺素

以巯基丙酸为稳定剂制备了水溶性CdSe/ZnS量子点,并采用滴涂法制备了CdSe/ZnS修饰的金电极（CdSe/ZnS/GE）,研究其电化学发光（ECL）性质,考察了pH、CdSe/ZnS浓度、扫描速度、静置时间等实验条件对ECL强度的影响。结果表明,在碱性溶液中,去甲肾上腺素（NE）在鲁米诺溶液中对CdSe/ZnS的电化学发光信号有明显的增敏作用,由此建立了一种检测去甲肾上腺素的新方法。当去甲肾上腺素的浓度（C_NE）在2.3×10^-5~1.0×10^-8 mol/L范围内时,去甲肾上腺素的浓度与相对电化学发光强度呈现良好的线性关系。线性回归方程为ΔI_ECL=118.788C_NE-15.333（R=0.994 4）,最低检测限（S/N=3）为0.33×10^-8 mol/L。     

分子印迹-碳纳米管修饰电极检测扑热息痛

以扑热息痛为模板,邻苯二胺为单体,采用电聚合法制备了分子印迹-多壁碳纳米管复合膜修饰电极,研究了扑热息痛在该修饰电极上的电化学行为。结果表明,该修饰电极对扑热息痛的电极反应具有明显的电催化活性。该修饰电极对扑热息痛的方波伏安检测线性范围为2.0×10-6—8.0×10-5mol/L,检出限为1.0×10-8mol/L。该修饰电极显示了良好的稳定性和重现性。     

紫外双光束单波长硝酸根原位监测传感器系统的研究

水中硝酸根含量的实时监测是一个亟待解决的现实问题,为了满足硝酸根监测的实时性要求,避免采样、预处理等繁琐的步骤,提出了一种新型的原位监测硝酸根传感器系统的研究设计,介绍了系统的工作原理和构成,该仪器利用双光束单波长标准测量法,不仅能有效消除材料及粒子散射对测量的干扰,而且简化了设计结构。并用紫外分光光度计进行了模拟实验,实验证明,这种新型的传感器系统能够满足指定水域的硝酸根实时监测要求。     

液态电极等离子体发射光谱技术检测金属离子的研究应用

快速准确的金属离子检测是涉及多个学科领域及检测技术的研究课题,文章综述了液体电极等离子体发射光谱技术在金属离子检测领域的研究及应用。首先介绍了基于电化学原理的电极法,包括离子选择性电极及阳极溶出法,及基于原子吸收或发射光谱等检测金属离子常用方法技术的原理及优缺点;然后阐述了基于等离子体的液体电极光谱技术的原理及特点,包括等离子体的产生机理、光谱特点以及其检测技术的优势;并按照液态电极数目及放电系统结构分成单液态电极及双液态电极放电系统两类,重点介绍了液态电极发射光谱技术的发展历程及研究进展,其中详细说明了ELCAD、SCGD、LS-APGD及毛细管放电等电解质放电系统的结构及特点;利用液态电极等离子体发射光谱技术,对铜、汞、银等重金属以及钠、钾、镁等活泼金属离子的检测限可达μg·L-1。最后探讨了该技术应用于检测金属离子的优势及存在的问题,并展望了其应用前景。     

Voltammetric detection of nitrate in water sample based on in situ copper-modified electrode

A simple and fast electroanalytical method for the detection of nitrate at an in situ copper-modified glassy carbon electrode (GCE) in an acidic media is proposed on the basis of square wave voltammetry. Since the fresh copper-modified electrode was formed in situ and the signals of nitrate were recorded in time, the whole experiment does not require sample preparation and oxygen removal from the solution degassed with nitrogen. Finally, a procedure for on-line electrochemical cleaning, the surface of GCE was employed to keep the copper film fresh. The whole experiment was rapid, in no more than 10 min. Under the optimal conditions, nitrates could be quantitatively determined in the range extending from 10 to 300 μM, a very good linear correlation (R?=?0.9996) can be observed when analyzing the relationship between the peak current and the ion concentration. In addition, the interferential effects of some common anions in water samples on the nitrate determination were also investigated. The results show that only nitrite ions could produce a distinct peak current at the same potential as nitrate does. When applying this method to detect nitrate in real water samples, the results exhibit good sensitivity. The procedure was also verified by the standard optical method.     

顺序注射-连续光谱测定水质多参数方法研究

针对水质多参数监测仪器的低功耗、微型化、集成化和智能化,研制了一种基于顺序注射分析技术（SIA）和连续光谱检测方法融合的微型测定原位水质多参数检测仪,系统设计的核心在于消解池结构设计且消解池作为检测池,以及微控技术顺序注射平台的原理设计和多参数联合消解测定流程设计。对融合SIA和连续光谱水质多参数原位分析的新方法进行实验研究。设计了基于国标水质检测标准的多参数顺序注射分析检测流程,基于分光光度检测方法,在使用连续光谱扫描测量的条件下,融合顺序注射分析技术对亚硝酸盐氮、硝酸盐氮、总氮、总磷的含量进行检测。测定消解前,对硝酸盐氮、亚硝酸盐氮进行直接光谱测量,测定消解后对总氮进行光谱检测,显色反应后,对总磷进行光谱检测。在本系统下,以亚硝酸盐氮、硝酸盐氮、总磷和总氮原位水质参数为测定对象,基于连续光谱分析,最小二乘法建立回归模型并绘制各参数的浓度-吸光度标准工作曲线,其拟合优度（即决定系数）≥0.989 9。配制已知亚硝酸盐氮、硝酸盐氮、总氮、总磷含量的混合溶液,按照上述的多参数检测流程,利用本系统绘制出的标准工作曲线测量4个参数,实验结果表明,实验参数重复性（相对标准偏差）RSD≤3.86%,系统可稳定、高效的分析不同水样中的亚硝酸盐氮、硝酸盐氮、总氮、总磷含量。基于SIA-连续光谱融合测定原位水质多参数检测方法研究,对于提升在线水质监测仪器的技术性能具有重要作用,微型多参数水质监测仪的研制具有良好的参数扩展前景,适用于多种水质在线监测平台。     

A voltammetric sensor based on GO–MWNTs hybrid nanomaterial-modified electrode for determination of carbendazim in soil and water samples

A voltammetric sensor for the determination of carbendazim was developed at a glassy carbon electrode modified with a hybrid nanomaterial (graphene oxide–multi-walled nanotubes/glassy carbon (GO–MWNTs/GC)). Its surface electrochemical property was studied with UV–Vis spectroscopy, TEM analysis, and electrochemical impedance spectroscopy. The electrochemical behavior of carbendazim was investigated on the modified electrode with cyclic voltammetry and differential pulse voltammetry. The influence of modifier dosage, buffer solution, pH, accumulation time, and scan rates on the determination was discussed. The results indicated that the reaction of carbendazim on the electrode was controlled by diffusion and was an irreversible process with two electrons. The effective area of GO–MWNTs/GC, anodic transfer coefficient, and apparent diffusion coefficient were calculated. The anodic peak current of carbendazim was linear with the concentration of carbendazim from 10 nM to 4 μM with a detection limit of 5 nM (S/N?=?3). The proposed sensor was successfully applied to the determination of carbendazim in soil and tap water.     

Electrochemical structure‐switching sensing using nanoplasmonic devices

In this article, the implementation of electrochemical plasmonic nanostructures functionalized with DNA‐based structure‐switching sensors is presented. eNanoSPR devices with open and microfluidic measurement cells are developed on the base of nanohole arrays in 100 nm gold film and applied for combined microscopic and electrochemical surface plasmon (eSPR) visualization. eSPR voltammograms and spectroscopy are performed using planar three electrode schematic with plasmonic nanostructure operated as working electrode. Limit of detection of eNanoSPR devices for oligonucleotide hybridization is estimated in the low nanomolar and applications for structure‐switching electro‐plasmonic sensing in complex liquids are discussed.     

Electrochemical methods for determination of thymine in medical pipefish samples based on HPMαFP/Ppy/GCE-modified electrode

A sensitive electrochemical method was developed for the voltammetric determination of thymine at a composite film-modified electrode 1-phenyl-3-methyl-4-(2-furoyl)-5-pyrazolone (HPMαFP)/polypyrrole (Ppy)/glassy carbon electrode (GCE). The electrochemical parameters of thymine were investigated by cyclic voltammetry and differential pulse voltammetry. In pH?=?7.4, one sensitive oxidation peak of thymine with E _pa?=?0.968 V was observed on the HPMαFP/PPy-modified electrode. The difference of peak potential (?E _pa) was 188 mV lower than that for bare GCE. Compared to the bare GCE and Ppy/GCE, the HPMαFP/Ppy/GCE-modified electrode showed an excellent electrocatalytic effect on the oxidation of thymine and displayed a shift of the oxidation potential in the negative direction with significant increase in the peak current. Under the optimum condition, the concentration calibration range and detection limit are 2?×?10^?6–1?×?10^?4 and 4.85?×?10^?7?M for thymine. This developed method had been applied to the direct determination of thymine in medical pipefish samples with satisfactory results.     

Stripping voltammetry of Pb and Cu using a microcantilever electrode

Microfabricated silicon microcantilevers coated with gold on one side have been used as working electrode in a three-electrode electrochemical arrangement. In addition to electrochemical current, cantilever bending has been used as a signal for monitoring electrode reactions on the cantilever surface. The microcantilever bending was measured by an optical beam deflection method as the surface potential was scanned and electrochemical reactions occurred on the surface. The microcantilever bending due to differential surface stress was used to sense Pb and Cu using cyclic voltammetry (CV) and linear sweep stripping voltammetry (LSSV).     

Electrochemical detection of trace cadmium in soil using a Nafion/stannum film-modified molecular wire carbon paste electrodes

In this paper, a novel Nafion polymer-coated stannum film-modified carbon paste electrode was developed for the analysis of trace cadmium by square wave anodic stripping voltammetry. The electronic conductive material—molecular wire (diphenylacetylene)—was employed as the binder instead of traditional mineral oil for fabricating this electrode. It was found that the prepared electrode possessed excellent electrochemical performance and increased electron transfer rate due to the introduction of molecular wire as a binder, and exhibited a better sensitivity and stability as well as high resistance to surfactants due to the synergistic effect of Nafion and stannum film. Under the optimal conditions, the stripping peak currents showed a good linear relationship with the Cd(II) concentration in the range from 1.0 to 80.0 μg L^?1 with a detection limit of 0.13 μg L^?1 (S/N?=?3). The developed electrode was further applied to the determination of Cd(II) in soil extracts with satisfactory results.