基于溶胶-凝胶及印制技术制备复合陶瓷碳pH电极

将溶胶－凝胶技术与丝网印制技术相结合研制了一种新型复合陶瓷碳pH电极和参比电极，并组合制备了PH复合电极，PH电极利用天然沸石作质子接受体，用溶胶－凝胶法进行固定，对溶胶－产法与印制技术相结合制作包埋沸石的复合陶瓷碳敏感的条件进行了实验，并对电极参数进行了测试，该电极测定范围为PH1－12，响应斜率为0.06V/dec。电极稳定性，重现性好，响应愉，利用此电极对多种水样进行了分析，取得了满意效果，采用该法制备离子选择性电极具有简易，价廉，易批量化生产和推广应用等特点。     

毛细管电泳-钴钛菁碳糊修饰电极电化学催化氧化测定羟胺和巯基类化合物

本文利用自制的毛细管电泳－电化学安培检测装置，以钴钛菁碳糊修饰电极为工作。电极，在中性磷酸体系缓冲溶液中，对四种羟胺和巯基类化合物的混合物进行了分离和测定，检测下限羟胺类化合物为５．０×１０－６ｍｏｌ／Ｌ巯基类化合物为１．０×１０－５ｍｏｌ／Ｌ。对实际尿样中的半胱氨酸进行检测，结果满意。     

毛细管电泳—钴钛菁碳糊修饰电极电化学催化氧化测定羟胺和巯基类…

本文利用自制的毛细管电泳－电化学安培检测装置，以钴钛菁碳糊修饰电极为工作电极。在中性磷酸体系缓冲溶液中，对四种羟胺和巯基类化合物的混合物进行了分离和测定，检测下限羟胺类化合物为５．０×１０＾－６ｍｏｌ／Ｌ巯基类化合物为１．０×１０＾－５ｍｏｌ／Ｌ。对     

以双核有机锡化合物为载体的PVC膜磷酸根离子敏感电极

以双（三苄基锡）氧化物为载体制备了一种对磷酸氢根离子具有良好电位响应性能的溶剂聚合膜离子敏感电极。在ｐＨ为７．２０±０．０２的测试液中，电极的线性响应范围为５ ×１０＾－６￣１０＾－１ｍｏｌ／Ｌ，斜率为－３０．１ｍＶ／ｄｅｃ．．用分别溶液法测得其对于各种阴离子的选择性次序：ＨＰＯ４＾２－￣Ｉ＾－〉Ｂｒ＾－〉Ｃｌ＾－〉Ａｃ〉ＳＯ４＾２－。膜相中荷电离子添加实验的结果表明，电极响应系中性载体作用机制。     

聚吡咯水杨酸修饰电极的电化学行为及水杨酸含量测定

本用电化学方法制备了聚吡咯－水杨酸修饰电极；并进行了电化学行为的研究，经电化学处理该是电极对水杨酸根具有选择性响应，响应线性范围在１．０×１０＾－＾５－１．０×１０＾－＾３ｍｏｌ／Ｌ之间。电极斜率为４０ｍＶ／ｐＣ，该电极具有较好的稳定性，响应时间在１８０－３００ｓ之间；电极寿命可达６０ｄ。     

采用粉末微电极技术改善电流型酶电极的输出性能

由于酶反应的特异性，酶电极在检测生物底物的工作中得到了较广泛的应用，然后电流型酶电极有以下的缺点，包括响应电流低，活性组份流失电极使用寿命下降以及响应电流的非线性等。本文根据粉末酶电极模型进行了动力学分析，得出在两极极端情况下粉末酶电极的电流响应动力学公式，以及由响应电流估算表观米氏常数的方法。采用了两种粉末酶电极（Ｃ－ＰＵ－ＧＯＤ和Ｃ－ＡＱ－ＤＢＦ－ＧＯＤ）对理论分析进行了验证。实验结果与理论推     

聚1-甲基-2-吡咯烷酮修饰碘离子化学传感器的研究

研究了１－甲基－２－吡咯烷酮在玻碳（ＧＣ）电极表面聚合的条件，测试了Ｉ－－聚１－甲基－２－吡咯烷酮化学传感器的电化学性能。所制电极检测Ｉ－响应线性范围２４×１０－４～０１ｍｏｌ／Ｌ，检测下限为１０×１０－４ｍｏｌ／Ｌ，电极的重现性及稳定性都较好，重复测定７次相对标准偏差为０７１％，可连续使用２５天。Ｃｌ－、Ｂｒ－、ＮＯ－３、ＳＯ２－４等阴离子对测定干扰较小     

LBL分子沉积法制备葡萄糖氧化酶电极

采用以静电力为主的逐层分子交替沉积技术制备葡萄糖氧化酶（GOD）电极.通过带有正电荷的聚二甲基二烯丙基铵盐酸盐（PDDA）和带有负电荷的GOD交替沉积在修饰有3-巯基-1-丙基磺酸钠（MPS）的金电极表面.以甲酸二茂铁为电子媒介体,用循环伏安法检测GOD电极对葡萄糖的响应.结果表明,当GOD电极组装层数小于4时,电流响应随着层数的增加而增大,超过4层时电流响应减小.其中4层GOD修饰电极的线性范围为0.55～6.63 mmol•L－1,当pH为7.0时,响应最大.同时电极的检测重现性能良好,相对标准偏差为2.4％.     

适合低PH范围测量的新型中性载体膜PH电极的研究

本文设计合成了一种在低ＰＨ范围对氢离子有很好Ｎｅｒｎｓｔ响应的新型中性载体－Ｎ，Ｎ－二辛基菸酰胺，并把它制成ＰＶＣ膜ＰＨ电极，测试了该电极的线性范围、选择性、稳定、重现性和内阻等各项性能参数，并试验了电极抗氢氟酸腐蚀的能力，该该电极用于氢氟酸的电离常数测定时获得了满意的结果。     

涂碳型PVC膜氧氟沙星选择电极的研制与应用

报道了一种以氧氟沙星碘化物与碘化铋的分子缔合物为电活性物的新型涂碳ＰＶＣ膜氧氟沙星选择电极．电极的能斯特响应范围为１．０×１０－５～３．２×１０－２ｍｏｌ／Ｌ，斜率为３１ｍＶ／ｐＣ，电极响应迅速，重现性好．用此电极对药片中的氧氟沙星进行测定，结果与紫外分光光度法相符．     

The electrochemical copolymerization of 3,4-dihydroxybenzoic acid and aniline at microdisk gold electrode and its amperometric determination for ascorbic acid

The electrochemical copolymerization of 3,4-dihydroxybenzoic acid (3,4-DHBA) and aniline was carried out at microdisk gold electrodes by means of cyclic voltammetric sweep. The polymer obtained on the electrode shows good electrochemical activity and high stability even though in neutral and weakly basic media. It was found that the response current of ascorbic acid was greatly enhanced at this composite polymer electrode. Moreover, the anodic overpotential was significantly reduced for about 200 mV (vs. SCE) compared with that obtained at bare gold electrodes. The electrode exhibits a rapid current response (less than 2 s) and a high sensitivity (0.21 AM(-1) cm(-2)). The dependence of response currents on the concentration of ascorbic acid was linear in the range of 1.0x10(-4)-1.0x10(-2) M. In addition this composite polymer modified electrode exhibits a high electrode stability for a long-term use.     

New cesium ion-selective electrodes based on anilino-(1,3-dioxo-2-indanylidene) acetonitrile derivatives

Cesium ion-selective PVC membrane electrodes based on anilino-(1,3-dioxo-2-indanylidene) acetonitrile derivatives as a novel class of neutral ionophores were examined. The ionophores were p-methoxyanilino-(1,3-dioxo-2-indanylidene) acetonitrile, p-methylanilino-(1,3-dioxo-2-indanylidene) acetonitrile and p-N,N-dimethylanilino-(1,3-dioxo-2-indanylidene) acetonitrile. The anilino-(1,3-dioxo-2-indanylidene) acetonitrile proved to work well with cesium, the corresponding electrodes display a response to this ion. The most favourable ionophore was p-methoxyanilino-(1,3-dioxo-2-indanylidene) acetonitrile, especially when the secondary ion exchanger potassium tetrakis (4-chlorophenyl) borate was incorporated in 2-nitrophenyl octyl ether for ion-selective electrode membrane construction. The response function was linear within the concentration range 10(-1)-2.5x10(-5) mol l(-1) and the slope was 52 mV decade(-1). The detection limit remained at 6.3x10(-6) mol(-1). The selectivity and response time of the electrode was studied and it was found that the electrode exhibited good selectivity for cesium over alkali, alkaline earth and some transition metal ions. The electrode response was stable over a wide pH range. The lifetime of the electrode was about 1 month.     

Permselectivity of neurotransmitters at overoxidized polypyrrole-film-coated glassy carbon electrodes

The permselectivity of neurotransmitters such as dopamine, epinephrine, and norepinephrine at overoxidized polypyrrole (OPPY)-film-coated glassy carbon electrodes has been investigated. The chemically-modified electrodes exhibit attractive permselectivity and antifouling properties of rejecting anionic species, e.g. ascorbate, etc. Compared with the response of neurotransmitters at modified electrodes overoxidized in phosphate buffer solution (pH 7.4), higher sensitivity and reversibility response can be obtained at modified electrodes overoxidized in sodium hydroxide solution. The effect of film thickness on the permselective response was tested. Rotating disk electrode experiments were used to determine the apparent diffusion coefficients of several electroactive solutes in the OPPY films. The influence of the hydrophobicity of the organic ions on the permeability within the polymer films was discussed. Dopamine and epinephrine were determined at the 1 x 10(-6)-1 x 10(-4) M level by means of voltammetry after an exposure period of 2 min in 0.1 M phosphate buffer (pH 7.4) with detection limits of 8 x 10(-7) M and 6 x 10(-7) M respectively.     

A glucose electrode based on carbon paste chemically modified with a ferrocene-containing siloxane polymer and glucose oxidase,coated with a poly(ester-sulfonic acid) cation-exchanger

A carbon-paste chemically modified with glucose oxidase and a ferrocene-containing siloxane polymer was further modified by coating the electrode surface with a poly(ester-sulfonic acid) cation-exchanger, Eastman AQ-29D. The polymer is obtained as a homogeneous aqueous dispersion at pH 5–6; when dried, the polymer coating is not water-soluble. The coating was shown not to be detrimental to the enzyme activity but to prevent electrochemically active anionic interferents such as ascorbate and urate from reaching the electrode surface. The polymer coating also prevented glucose oxidase from leaking out of the carbon paste into the contacting solution and protected the electrode surface from fouling agents present in urine and bovine serum albumin. Uncoated electrodes lost some 10-2-15% of their original response to glucose after storage in buffer for three weeks whereas the response of the coated electrodes remained constant. Calibration curves for glucose were strictly linear up to about 5 mM for uncoated and up to 20 mM for coated electrodes. The response current to glucose was not decreased after coating.     

Calcium ion selective membrane electrode

The calcium salts of the mono- and diesters of [4-(1,1,3,3-tetramethylbutyl)phenyl phosphoric acid] have been prepared, and the individual esters as well as mixtures of the esters have been used with several varieties of polyvinyl chloride to construct macro membrane electrodes selective to calcium ions. These electrodes have been calibrated by using solutions of CaCl₂ and Ca ion buffers. The mixed ester electrodes showed Nernstian response in the concentration range 10^-1 to 10^-7M; the diester electrodes showed Nernstian response down to 7.9 x 10^-8M. The detection limit of the mixed ester electrode was 10^-8M, whereas that of the diester electrode was 7.9 x 10^-9M. Contrary to these results, the monoester electrodes showed unsatisfactory behavior. The responses of both the mixed ester and diester electrodes to calcium ions were not affected by the presence of sodium, potassium, or other divalent ions. Only ferric and lanthanum ions showed interferences with the electrode response to calcium ions. p]The electrode response was independent of pH in the approximate range 5–8 at a CaCl₂ concentration of 10^-4M. As the Ca ion concentration was increased, the range of pH independence widened to approximately 4–8. The dynamic response time constant of the mixed ester electrode was in the range 0.7–1.5 sec, whereas that of the diester electrode was in the range 0.5–0.75 sec.     

Novel hydrogen peroxide sensors based on peroxidase-carrying poly[pyrrole-co-[4-(3-pyrrolyl)butanesulfonate]] copolymer films.

Amperometric hydrogen peroxide biosensors were fabricated by incorporating horseradish peroxidase (HRP) into poly[pyrrole-co-[4-(3-pyrrolyl)butanesulfonate]] (Py-PS) copolymer films deposited on an SnO2 electrode surface by electropolymerization. The HRP/Py-PS electrodes exhibited an extended dynamic range and a markedly improved operational and storage stability, compared with HRP-incorporated polypyrrole (PPy) electrodes prepared under similar conditions. The linear range was expanded from 10(-7)-10(-4) M to 10(-7)-10(-3) M H2O2. In about 80 measurements over three weeks, the HRP/Py-PS electrode retained 60% of its initial response, while the HRP/PPy electrode almost completely lost activity. The influence of the electrodeposition solution pH on the sensor response was also investigated. Our results suggest that an expansion of the linear range and an enhancement of lifetime are due to electrostatic interactions of HRP with a negatively-charged Py-PS copolymer.     

The Ternary Coppersilver Selenide—A New Homogeneous Solid State Ion-Selective Electrode for Copper (II)

Abstract

The performance characteristics of a copper (II) ion-selective electrode, based on pressed-pellet membrane of ternary CuAgSe, are reported. The sensing material is isostructural with the natural mineral β -eucairite and shows high corrosion resistivity which results in stable and reproducible electrode performance upon ageing. The electrodes exhibit a linear Nernstian response dawn to 5.10^?8 M in non buffered medium and down to 10^?13M in copper-glycine ion buffer. Data on the electrode stability for a period of two and a half years, on the electrode response time, pH-dependence, selectivity etc. are also presented.     

Anion selective polymeric membrane electrodes based on cyclopalladated amine complexes

The potentiometric anion selectivity of two polymer membrane based electrodes (I and II) formulated with two new cyclopalladated amine complexes as the active components are examined. The electrodes exhibit a non-Hofmeister selectivity pattern with a significantly enhanced response towards thiocyanate, iodide and nitrite. The graph potential versus log c is linear over the concentration range 10(-6)-6x10(-2) M thiocyanate with electrode I and 10(-6)-10(-3) M with electrode II; 10(-5)-10(-2) M iodide with electrode I and 10(-3)-6x10(-2) M with electrode II; and 10(-3)-6x10(-2) M nitrite with both electrodes. The influence of the plasticizer and pH are studied. The potentiometric selectivity coefficients for I, II and blank membrane electrodes are reported. The selective interaction between Pd(II) thiocyanate, iodide and nitrite is postulated to be the reason for its higher response.     

496—Cyclic voltammetric studies on the application of carbon elctrodes in the determination of oxalic acid

The application of carbon paste and glassy carbon electrodes in the analysis of oxalic acid was investigated by comparing the characteristics of cyclic voltammograms of oxalic acid obtained in various supporting electrolytes (acetate, borate, citrate, phosphate, etc.). When a semi-micro carbon paste electrode (area 0.49 cm²) was used, the oxalic acid was oxidized at +1.0 to +1.2 V vs Ag|AgCl yielding current in the μA range (scan rate 50 mV/s) for oxalic acid concentration of approximately 10^?4M. Oxalic acid oxidation was observed under both acidic and alkaline conditions. The presence of chloride ions or oxygen did not have any deleterious effect on the electrode response. The peak current was reproducible for repeated scans obtained with the same electrode after brief stirring. The glassy carbon electrode was found to be less suitable for oxalic acid oxidation studies because the peaks in the voltammograms were poorly defined and the current response was markedly reduced. These investigations suggest that carbon paste electrodes are sensitive and stable for oxalic acid oxidation studies. A plot of the peak currents obtained with carbon paste electrode for different concentrations of oxalic acid between 1×10^?4M to 1×10^?3M was linear and reproducible. It is suggested that a flow through carbon paste electrode coupled to a chromatographic column can be used in the development of a sensitive method for oxalic acid analysis in biological samples.     

邻菲咯啉冠醚衍生物为载体的伯胺药物电极及机理研究

合成了邻菲咯啉-18-冠-6等四种含邻菲咯啉结构的冠醚化合物, 并用作载体制备伯胺电极, 以苄胺为模型化合物, 研究了电极特性, 并制备了测试美西律药物的选择性电极。研究了实验条件对电极性能的影响。用正交多项式回归法优化电极的膜组成。苄胺电极的线性范围1.0×10^-5~0.1mol/L, 斜率55.6mV/pc, 检测下限2.0×10^-6mol/L。美西律电极的线性范围6.0×10^-6~0.1mol/L, 检测下限8.0×10^-7mol, 斜率58.0mV/pc。同时研究了冠醚推动伯胺穿透大块液膜的传输行为。