对苯二酚在铁磁性葡聚糖微球修饰电极上的电化学行为

对苯二酚主要用作照相显影剂、染料、食品抗氧化剂等,但由于具有毒性和难以降解,给环境造成了一定的污染。由于对苯二酚具有电化学活性,利用各种材料,如聚合物膜[1]、自组装单分子层[2]、纳米材料[3]等制备修饰电极测定对苯二酚引起人们广泛关注。磁性高分子微球是通过适当方法     

联吡啶桥联双核铜配合物修饰玻碳电极对对苯二酚的电催化作用及测定

采用电沉积方法将新型双核铜配合物修饰于玻碳(GC)电极表面制得[LCu]2BP/GC电极。研究了[LCu]2BP/GC电极的电化学性质,并发现该电极对对苯二酚具有良好的电催化作用。考察了该电极作为对苯二酚传感器的操作条件,结果表明:修饰电极在pH 5.0 PBS缓冲溶液,0.0~0.5 V电位范围内进行半微分线性扫描,其催化电流峰高与对苯二酚浓度在1.00×10-6~3.00×10-3mol/L范围内呈线性关系。检出限为2.00×10-7mol/L,相对标准偏差为1.09%(n=7)。用于测定合成样品中的对苯二酚含量,回收率在98%~102%之间,结果令人满意。     

爆炸残留物的毛细管电泳检测

1引言爆炸是恐怖袭击的常用手段。对痕量爆炸残留物进行高效检测,从而准确判断炸药的成分和种类,能够为侦破案件提供重要的线索和证据[1,2]。近年来,毛细管电泳技术初步显示了其在爆炸物检验方面的巨大潜力[3～6]。本实验基于毛细管电泳间接紫外吸收检测[7,8]和胶束电动色谱[9],建立了痕量爆炸残余物的系统分析检验方法,通过对爆炸瞬间产生的痕量     

银盘电极交流示波计时电位法及其机理的研究

示波分析中 ,电极的种类和预处理的好坏直接影响示波分析的范围和结果 ,常用的汞膜电极的灵敏度较低 ,限制了其应用 .因此 ,开发新电极是示波分析发展的一个重要途径 .银是一种较好的电极材料 ,具有制备简单、无汞污染等优点 ,以它为工作电极利用阴极溶出 [1,2 ] 和阳极溶出 [3] 进行测定的灵敏度较高 .冶保献等 [4 ]报道了血红蛋白在普通银电极上能进行直接电子传递 ,并对银基的特异功能引起关注 .本文对银盘电极的示波计时电位法及其机理进行了研究 .与用汞膜电极的示波计时电位法相比 ,可使检测下限降低 2～ 3个数量级 ,有望成为痕量分析…     

超微电极技术与应用

综述超微电极的特点、分类、制备；超微电极在生物体细胞分析、单分子分析、固体电化学、化学动力学参数测定及痕量物质检测等方面的应用．     

结晶紫-高碘酸钾体系催化动力学光度法测定痕量钌(Ⅲ)

测定金属元素主要的主法有光度法、原子吸收法、荧光法[1,2]等.近年来催化动力学光度法测定金属元素以其灵敏度高、检测限低倍受分析工作者重视,适合于痕量分析,尤其适合于痕量钌(Ⅲ),采用有机染料作为检测组分.     

催化光度法测定痕量对苯二酚

在硫酸介质中，以草酸为活化剂，痕量对苯二酚对碘酸钾氧化天青Ⅱ的褪色反应具有明显的催化作用，据此建立了催化光度法测定痕量对苯二酚的新方法。方法的线性范围是0．04～1．20mg／L，检出限为0．008mg／L。方法操作简便，灵敏度高，选择性好，用于自来水、实验室废水和显影液中对苯二酚的测定，结果满意。     

纳米La(OH)3修饰电极对邻苯二酚和对苯二酚的同时测定

研究了纳米La(OH)3修饰电极的制备及其对邻苯二酚和对苯二酚的电催化作用。讨论了支持电解质种类、酸度等对邻苯二酚和对苯二酚伏安响应的影响,获得了较为优化的实验条件。在0.1mol/LPBS(pH7.0)中,采用示差脉冲伏安测定邻苯二酚和对苯二酚,其浓度与氧化峰电流线性关系良好。共存的多种金属离子、抗坏血酸及等量的苯酚等不干扰测定。该电极用于模拟废水样中邻苯二酚和对苯二酚的测定,结果令人满意。     

催化动力学测定痕量对苯二酚

研究了在pH7.3的KH2PO4 Na2HPO4缓冲介质中,痕量对苯二酚催化高碘酸钾氧化靛红褪色的新指示反应及其动力学条件,建立了动力学光度法测定痕量对苯二酚的新方法。该方法检出限为6.8×10-6g L,线性范围是0.04～0 18μg mL和0.28～0.54μg mL。可用于显影废液中对苯二酚的测定。     

聚L-丝氨酸修饰电极伏安法测定对乙酰氨基酚

对乙酰氨基粉(扑热息痛)为芳环对位取代的酰氨类药物,有解热、镇痛作用。临床上广泛用于感冒发烧、关节痛、神经痛及偏头痛、癌性痛及手术后止痛[1]。但过多服用对乙酰氨基酚对人体会造成伤害,对消化系统的影响主要表现为恶心、呕吐、压食、出汗、腹痛等症状;对泌尿系统、血液系统、呼吸系统都有影响,还能使对阿司匹灵过敏患者的支气管痉挛加重,严重时会抑制呼吸中枢。因此建立对乙酰氨基酚的灵敏检测方法是非常必要的。当前用于检测对乙酰氨基酚的方法主要有滴定法[2]、分光光度法[3]、高效液相色谱法[4]、毛细管电泳[5]、荧光法[6]以及电…     

用氧化还原聚合物修饰多孔电极

对３种类型Ｎａｆｉｏｎ／Ｏｓ（ｂｐｙ）３Ｃｌ２修饰电极的研究结果表明，单位表观电极面积上中继体载量比为：乙炔黑粉末微电极（Ａ）：Ｔｅｆｌｏｎ粘结的乙炔黑膜电极（Ｂ）：平面玻碳电极（Ｃ）＝１０＾３：１０＾２：１．Ａ比Ｂ及Ｃ更容易在真实表面上形成花天酒地而均匀的修饰层而有利于层内的电荷传递。在Ａ类电极基础上制行的葡萄糖酶电极在１０ｍｍｏｌ／Ｌ葡萄糖溶液中的响应电流密度高达４．６×１０＾－＾４Ａ／ｃｍ＾     

Side effects in measurements of selectivity coefficients of solid state ion selective electrodes

The influence of various factors such as solubility, the oxidation of the membrane, and the contamination of the solution, on the experimental values of the selectivity coefficients of solid state sulphide ion selective electrodes is discussed. A new method for the evaluation of very small selectivity coefficients, based on the addition of reagents forming complexes or insoluble salts with the main ion, is proposed. By means of this method, selectivity coefficients for silver, copper, cadmium and lead ion selective electrodes have been determined, which are in far better agreement with thermodynamic values than those described in the literature.     

Carbon-Filled Polymer Paste Reference Electrodes

Abstract

Inexpensive, disposable, carbon-filled polymer paste reference electrodes are reported. These electrodes are designed for use in conjuction with carbon-filled polymer paste ion-selective probes reported earlier. Attachment of integrated electronics is easily achieved.     

对季鏻与季鉮离子具有电位响应的二元酸酯PVC膜电极

研究发现二元酸酯PVC膜电极对季鏻和季鉮盐均具有能斯特响应。电极的响应机理是由于季鏻、季鉮阳离子的正电中心与电子云密度较大的酯中苯环产生次级力作用所致。     

新型硫醇硫组合电极研制及性能测试

把玻璃参比电极、环状的银-硫化银指示电极、以及铂丝屏蔽电极组合形成新型硫醇硫组合电极,研究了在含有0.2 mol/L硫离子的醇-水-氨介质中,在表面活性剂存在下,以环状银电极为阳极,恒定微电流电沉积的方式制备硫化银敏感层的条件。由此法制得的新型硫醇硫组合电极在Ag 浓度为1.0×10-1~1.0×10-5mol/L范围内斜率为59.0±0.5 mV/pC,测量下限为2.2×10-6mol/L,与同类商品电极相比,响应速度快、记忆效应小、重复性好、电位稳定,易于批量生产,具有较强的适应性和应用价值。     

A surface renewable iridium oxide-glass composite hydrogen ion electrode

A robust and surface renewable iridium oxide-based pH glass composite electrode was prepared by modifying glass matrix with iridium oxide particles. Fine glass powder coated with iridium oxide was prepared by pyrolyzing ammonium hexachloroiridate-coated glass powder under oxygen atmosphere. First the glass powder was molded into a disk, by using a press, then was sintered in high temperature, and was finally fabricated. The electrode showed linear response between pH 1 and 13 with close slopes to the theoretical value, − 59.2 mV/pH. The electrode showed low hysteresis upon sudden changes of pH from 2 to 6, but in extreme conditions, from pH 13 to 1, it showed values near 16 mV. The electrode maintained the pH response for 36 days, without a significant slope drift, in various storage conditions — deionized water, a pH 7 buffer solution, 4 M KCl, and even in the air. Most of the cations and anions, except electrochemically active compounds or ions, did not interfere with the electrodes seriously. The electrode surface can be renewed reproducibly, by a simple grinding process whenever it becomes fouled or deactivated. The electrode matrix was durable and showed extended lifetime although it was ground repeatedly with 2000 grit SiC emery paper for surface renewal.     

Electroanalytical Determination of Vancomycin at a Graphene‐modified Electrode: Comparison of Electrochemical Property between Graphene,Carbon Nanotube,and Carbon Black

Carbon nanotube, graphene and carbon black, as electrode modifiers, were compared and evaluated for the electrochemical determination of vancomycin. Among them, the best results were obtained at the graphene‐modified electrode. Additions of vancomycin using square wave voltammetry at the graphene‐modified electrode showed a linear range from 0.70 μM to 50 μM and a detection limit of 0.20 μM was obtained. To control the correct dose of vancomycin and reduce its side effects, its accurate determination in blood plasma is very important. Therefore, the method was applied for the vancomycin determination in spiked human plasma samples and satisfactory recoveries were observed. The developed method exhibited fast analysis, high sensitivity, good repeatability and freedom from other interfering species.     

双层聚合膜可乐定选择性涂丝电极的研究

报告一种新型双层聚合膜可乐定涂丝电极的研制。通过电化学聚合,在铂丝表面修饰一层具有导电性能的聚苯胺薄膜,外层涂PVC膜(含四苯硼酸-可乐定活性物质)。此种电极既保持了涂丝电极的优点,又具备较好的稳定性和重现性,连续测定8h,电位值漂移0.8mV,线性范围为1×10^-1～8×10^-6mol/L,电极响应斜率56.7mV/decade;用加入稀释法测定了回收率,平均回收率为100.9%,标准偏差为1.3%。