基于无序介孔碳的全固态自支撑聚合物膜铅离子选择性微型电极

将无序介孔碳材料填充到尖端直径约150 μm的毛细玻璃管内,利用其多孔结构将铅离子选择性敏感 膜吸附于电极尖端内部,制备了基于无序介孔碳的全固态自支撑聚合物膜铅离子选择性微型电极（Pb2+ －ISμE）。 采用循环伏安法（CV）和电化学阻抗法对所制备电极的电化学性质进行表征,并考察了其电位响应性能。结果 表明,基于无序介孔碳的微型电极具有微电极所特有的“S”型循环伏安曲线,且由于电极材料的多孔性表现 出较大的双电层电容特性,所构建的Pb2+ －ISμE测定Pb2+ 的线性范围为1. 0 × 10－7 ～1. 0 × 10－4 mol/L,响应斜率 为（28. 9 ± 0. 5）mV/dec,检出限为 4. 0 × 10－8 mol/L。该 Pb2+ －ISμE 表现出良好的选择性、稳定性和重复性, 并成功应用于海岸带沉积物加标孔隙水中Pb2+ 的测定。该文为微型电极的制备提供了一种简单、便捷的方法, 并为微环境或微量样品中离子的测定提供了一种有效的检测手段。     

冠醚载体离子电极的选择特性研究

阴离子选择电极选择性系数随干扰离子r_j/z_j的变化规律已有报道,但冠醚为中性载体的金属离子电极的选择性系数规律未见报道。本文采用不同桥间结构的11种苯并双冠醚作为中性载体,从钾电极出发探讨了不同冠醚电极选择性系数与干扰离子r_j/z_j间的关系;并以4种烃型双冠醚为中性载体,分别考察了它们对Li~+、Rb~+、Cs~+、Ag~+、Ba~(2+)离子的响应规律。 1 实验部分     

反对数放大器的试制及其在离子选择电极测量上的应用

近十几年来,离子选择电极分析技术已在许多领域获得广泛应用,与离子选择电极配套的测量仪器可以归纳为下列三类: (1) 高输入阻抗毫伏计,直接测量离子选择电极电池毫伏值,然后计算被测离子浓度。 (2) 离子活度计,用以测量离子活度的负对数(pX=-1ogo_x)值,仪器按照pX分度,如用来测量pH即为pH计。 (3) 带反对数放大器或微型数据处理机的仪器,可从仪器上直接读出离子浓度,便于记录及打印。关于反对数放大器用于离子选择电极测量是近几年才开始出现的,在此以前Gran在电位滴定法中采用反对数座标作图法,使计算测量结     

TaF_6~-PVC膜电极的放射性示踪研究

示踪原子是研究离子选择电极膜导电机理的一种良好工具。Schwabe在玻璃电极球泡内,置放示踪原子氚,电解20小时,纠正了长期存在的氢离子能透过玻璃膜的错误论断。Moody用~(45)Ca和~(36)Cl研究PVC膜钙电极,证明是Ca~(2+)导电,而Cl~-不能透过膜。Simon用示踪原子研究K~+电极,得出K~+、Cl~-和载体在膜中各剖面情况,计算了各离子的迁移数。Chaudhari用~(210)pb为示踪原子,研究铅离子选择电极的表面吸附和交换反应,     

N263~+-AuCl_4~-PVC膜金离子选择电极的研制

以 AuCl_4~-为响应离子的 Au(Ⅲ)离子选择电极已有报导,但尚未见有基于季铵盐-AuCl_4~-体系的电极。我们采用 N263~+-AuCl_4~-作电活性物质,以 DBP作溶剂,研制了 PVC 膜金离子选择电极。电极制作简单,性能良好,可用于金矿石及金矿“贵液”中金的测定。一、仪器与试剂pHS-2型酸度计;213型饱和甘汞电极。N263(上海有机所);正己烷(化学纯);PVC 粉(上海燎     

四苯硼酸盐PVC膜铵离子选择电极的研制

以往,常用氨气敏电极测定铵盐,测定时须加入强碱(如氢氧化钠)使 NH_4~+转化为 NH_3。为了直接测定 NH_4~+,同时简化电极,我们研制了四苯硼酸盐 PVC 膜 NH_4~+离子选择电极。     

介体溶剂在碱金属PVC膜离子电极中选择性的研究

近年来,文献报道了几种 Li~+、Cs~+ 等离子交换剂 PVC 膜电极.这类电极对离子的选择性除同活性物质本身的性质有关,还与介体溶剂的性质有关系.本文考察了不同介体溶剂的四苯硼酸盐 PVC 膜对碱金属离子的选择性,探讨了不同介体溶剂的膜对选择性的影响.所得结果有助于研制性能良好的碱金属离子选择电极.     

γ干扰素免疫电极及其响应机理的研究

在醋纤维孔膜上利用溴化氰固定了马抗人γ干扰素抗体。抗体膜经竞争性温育反应后置于碘离子选择电极上而构成免疫电极; 另一碘电极与参比膜作为参比电极。测定了电极在0.1mmol.dm^-3KI+4.4mmol.dm^-3H2O2+0.1mol.dm^-3柠檬酸盐,PH5.0缓冲液中响应电位, 研究了温度反应时间、电解液组成等因对电极响应影响,提出了电极向应线性化方法, 并得到了实验验证。     

PVC膜对硝基酚离子选择电极对三溴酚离子的响应性能及在工业废水分析中的应用

介绍了以碱性染料乙基紫阳离子EV~+(Ethyl·Violet)与对硝基酚阴离子NPO~-(Nitrophenol)离子缔合物EV~+NPO~-为电活性物质的PVC膜(Polyvinyl Chloride)对硝基酚离子选择电极对三溴酚离子TBPO~-(Tribromophenol)的响应性能的测试方法以及电极响应的特性参数,并利用此电极对工业废水中酚的总含量进行测定。测试结果与容量方法及比色法结果比较,表明此方法具有较高的准确度。     

聚合物在离子选择电极上的应用

本文概述了聚合物膜离子选择电极的发展、制备、应用等方面的研究情况。分别对固态膜类和液膜类聚合物膜离子选择电极的优缺点和发展前景进行了分析,并讨论了聚合物在膜电极中的作用,以及聚合物的结构对膜电极性能的影响。     

离子选择电极的进展

本文是有关离子选择电极发展近况的综述。Arnold和Solsky于1986年发表了一篇关于离子选择电极(ISE)的综述,全面介绍了自1983年至1985年有关这方面的工作。本文根据1988年底以前的文献,突出一些有代表性的文章,着重介绍了中性载体膜电极、敏化电极、生物电极和ISE在流动注射分析(FIA)和生物医学分析中的应用。     

Stability and Lifetime of Potassium Solid‐Contact Ion Selective Electrodes for Continuous and Autonomous Measurements

The current generation of solid‐contact ion‐selective electrodes (SC‐ISE) suffer from lack of stability and lifetime. When using such sensors for remote, continuous, or autonomous measurements, these analytical characteristics are especially critical. In this work we compare several different configurations of ISEs to be deployed for monitoring in extreme environments, and present a novel configuration to improve performance. In particular we compare a polymeric hydrogel‐based ISE, used previously in the Wet Chemistry Lab on the Phoenix Mars Lander, with three variations of solid supported nanoporous carbon‐based ISEs. The symmetric membrane (SM) solid contact ISE (SM‐SC‐ISE) shows promise in overcoming many of the analytical problems encountered with hydrogel and solid‐state devices. The results indicate that sensors based on the SM configuration provide improvements in both stability, and most importantly reproducibility, over other existing SC‐ISEs. Future work will continue testing the SM configuration for use in a variety of extreme environments, including continuous monitoring and in‐situ analyses in extraterrestrial environments.     

Automated ion-selective measurement of lithium in serum. A practical approach to result-level verification in a two-way method validation

 The Quality Assurance Department of Medix Diacor Labservice evaluated a two-way method validation procedure for serum lithium quantification in therapeutic drug monitoring In the process of a company fusion and rationalization of two considerably large production lines, three independent ion-selective electrode (ISE) methods were surveyed, among many others. While tailoring the new medical laboratory production, subcontracting from a collaborating company was discontinued. Likewise, modernization of the ISE instrumentation was unavoidable to increase throughput and effectiveness. It was important that the new result levels should be comparable both with the former subcontractor's levels and with the levels reported from the previously existing instrumentation. The aim of this study was to evaluate the most crucial performance characteristics of a novel lithium method in comparison to the two ISE test methods being withdrawn. The standardized lithium test method was inspected in terms of linear measurement range, analytical variation, bias, past and on-going proficiency testing, in addition to method comparison, to achieve the desired analytical goals. Fulfilling the accreditation requirements in terms of the introduced method validation parameters is discussed. Received: 19 April 2000 / Accepted: 26 July 2000     

Selectivity and specificity in analytical chemistry. General considerations and attempt of a definition and quantification

Selectivity and specificity are performance characteristics of analytical methods which are frequently used in analytical literature. In general, the terms are applied verbally and a quantification of selectivity and specificity is given rarely. Excepted are methods like chromatography and ISE sensoring which use individual quantities such as selectivity coefficients, indices and other parameters to characterize analytical procedures and systems. Here a proposal is given to characterize selectivity and specificity quantitatively by relative values in a range of 0 to 1 expressing so a certain degree of selectivity and specificity. By examples it will be shown that the derived quantities characterize analytical methods and problems in a plausible way.     

Selectivity and specificity in analytical chemistry. General considerations and attempt of a definition and quantification

Selectivity and specificity are performance characteristics of analytical methods which are frequently used in analytical literature. In general, the terms are applied verbally and a quantification of selectivity and specificity is given rarely. Excepted are methods like chromatography and ISE sensoring which use individual quantities such as selectivity coefficients, indices and other parameters to characterize analytical procedures and systems. Here a proposal is given to characterize selectivity and specificity quantitatively by relative values in a range of 0 to 1 expressing so a certain degree of selectivity and specificity. By examples it will be shown that the derived quantities characterize analytical methods and problems in a plausible way.     

The associations of macrocyclic ethers with cations in 1,4-dioxane/water mixtures; potentiometric Na+ and K+ binding measurements and computational study

This paper deals with the study of different degrees of association constants of Na⁺ and K⁺ ions with macrocycles of [12]crown-4, [15]crown-5, [18]crown-6, and Diaza[18]crown-6 in (1:1)dioxane/water mixture using the sodium and potassium ion selective electrodes (ISE). The gas phase molecular mechanical and quantum chemical calculations of [18]crown-6 and diaza[18]crown-6 were performed at MM+, AM1, MINDO/3, HF/6-31G(d), and B3LYP/6-31G(d) levels with the help of Gaussian03 program. Conformational abilities were compared with the ion binding results of ISE measurements. The results were also discussed in terms of oxygen charges and enthalpy stabilized association mechanism.     

Fullerene-based electrochemical buffer layer for ion-selective electrodes

In this work, C(60) fullerene is used as an electrochemical mediator for the development of an all-solid-state ISE. The unique electrochemical characteristics of the fullerenes allow for the facile ion-to-electron transduction across the ionically active polymeric ion-selective membrane and the electrochemically active glassy carbon transducer. The interfacial ion-to-electron charge transfer was investigated by Electrochemical Impedance Spectroscopy. The study of the analytical characteristics of a model potassium-selective electrode, together with the EIS studies, reveals that, indeed, the interfacial C(60) electrochemically active layer facilitates the ion-to-electron transduction, providing a stable and reversible solid-state ISE system. This finding is a significant contribution to the efforts aiming at overcoming one of the most significant drawbacks of the solid-state ISEs, that is the potential drift observed during continuous measurements, and could lead to the development of both cation- and anion-sensitive systems.     

Development and application of a fully automated,battery-operated,computerized field-based fluoride monitor

An automated, portable, battery-operated, computerized field-based monitor for the determination of fluoride based on the use of ion-selective electrode (ISE) potentiometry has been developed with the aid of low-powered complementary metal oxide semiconductor (CMOS) devices. The whole analytical cycle involving the rinsing of the cell, sampling, stirring, dosing of standards to the sample and data acquisition and manipulation is under microprocessor control. The modular instrument consists of pumps, valves, a flow-through cell containing a reference electrode, a fluoride ISE, a temperature probe and a stirrer, a microprocessor with a real-time clock, a pump-valve-stirrer interface, a portable terminal and a 12-V lead-acid battery to power all the instrumentation. The software for the application and monitoring functions for the instrument is written at assembler level and programmed into a CMOS erasable programmable read only memory (EPROM). The instrument is currently designed to determine fluoride in natural and fluoridated waters and is based on a double standard addition method, although the monitor can be modified easily to suit other appropriate ISE systems. Instrumental performance was evaluated with synthetic and real water samples both in the batch and continuous modes. The monitor can be used to carry out on-line fluoride determinations of water samples continuously for 1 week without anyone being attendance.     

叠层型串联ISE的电分析化学性能与Nernst倍增效应

设计了多元叠层型串联ISE,结构紧凑,组装简便,适用于微体积样液分析。对四元叠层型串联ISE的试验表明:与现行ISE比较,其线性响应斜率、测定精密度与灵敏度均增大4倍,但响应速度、选择性系数与检测下限不变。