用于非水介质分析的新型离子选择电极: 水膜电极的设想及验证

液膜离子选择电极的研究发展迅速,但迄今只是局限于用有机溶液作为液膜,用来测定水溶液中的组分。本文首次提出一种新型离子选择电极——水膜电极。采用水溶液作为液膜,可分析有机溶液中的组分。这种电极用于非水介质中的分析,有其独特的优点,可直接测量非水溶液中某种离子的平衡活度(或浓度),对理论研究有较大的意义。     

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。     

以乙基紫为电活性物质的PVC膜碘离子电极的研制

对于不同活动载体的碘离子选择电极的研制与应用,国内外已有报道。如王彦等用水溶液沉淀法制备电活性物质,G．A．rechnitz等报道了AgI——硅橡胶膜电极等。上述电极在敏感膜的制备中多采用水溶液沉淀法或有机溶剂多次萃取的方法来制备电活性物质,操作较繁。本文报道直接以乙基紫为电活性物质制备PVC膜,然后在碘离子标准溶液中转型活化,获得了性能较佳的碘离子电极。     

稀土离子选择电极的研制

(一)本文首次提出一类新型离子选择电极——水膜电极。推导了水膜电极遵循的能斯特方程式。具体研制了氯化钕水膜电极,用于测定环己酮中Na(PMBP)₃螯合物。结果与理论相符合。研究了参比电极电位在非水介质中保持稳定的条件。发现了两不相溶溶液界面上的电位响应可以是双向的,而且响应曲线斜率的绝对值基本相同。水膜离子选择电极可以做到完全不受有机溶剂的腐蚀,这是水膜电极的优点。     

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。     

重稀土离子电极的研制及其应用

稀土分离流程中,需要能随时测定稀土含量而又简便的分析方法,离子选择电极可能适应这种需要。我们在稀土电极研究的基础上,研制了重稀土离子选择电极,并以该电极膜制成重稀土流通池,将其应用在流动注射分析中,可能是重稀土分析中较理想的方法之一。1 主要仪器和试剂 主要仪器有PW 9409酸度计(Philips),FlA-T_2通用流动注射仪(东北电力学院仪器仪     

用交流阻抗法研究某些离子选择电极的响应特性

用交流阻抗法研究了两种液膜胆R汁酸电极和两种聚氯乙烯(PVC)膜钙离子选择电极. 从体电阻R_b和电荷传递电阻R_(ct)得到膜内离子迁移活化能E_a, 及电极的表观标准交换电流密度i°_0等信息. 结果表明: E_a比R_b更能反映离子在膜内迁移的情况, 离子在PVC膜中的迁移比在液膜中困难得多; i°_0能在一定程度上反映电极性能的优劣等。     

非水溶剂电位法的研究 Ⅰ.水膜镍电极在磷酸三丁酯中的响应

本文以镍水膜电极,测定有机溶剂-磷酸三丁酯中的镍离子。研究了电极的制备,水膜中镍离子浓度和PH值、水膜支撑材料、支持电解质对电极响应的影响。电极对3.2×10~(-4)—1.0×10~(-1)M范围内的镍离子呈能斯特响应,响应的时间为1—3分钟,响应的稳定性和重现性好。所用参比电极-Pt/(I_3-+I-)电极在多种有机溶剂中有稳定的电位。指示电极与参比电极均具有结构简单,容易制备的特点。     

稀土离子选择电极活性材料的研究

我们曾经研究了功能高分子活性材料的稀土离子选择电极。然而至今尚未见到这种活性材料的制备方法以及电极膜中稀土离子价态方面的报道。本文报导了这一方面的研究结果。     

用于高性能铅离子选择电极的含氮有机物载体

本文系统地综述高性能铅离子选择电极中掺杂于膜内的含氮有机物铅离子传感载体,如双席夫碱、吡啶酰胺、酰羟胺、苯腙,以及载体分子结构特征与铅离子电极性能之间的关系。电极对铅离子的选择性能与载体分子结构密切相关,无论是在载体还是在膜基体中引入氰基都可以明显改善铅离子电极探测下限;加强传感机理的深入研究,为高性能载体的研究指明方向。     

离子缔合型离子选择电极的研究 I: PVC膜铬(VI)离子选择电极的研制的和应用

A new Cr(VI)-selective electrode of PVC membrane based on triheptyl dodecyl ammonium iodide is described. The response of the electrode is Nernstian for Cr(VI) concentration down to 2X10-6M in 0.03-0.13N HF solution. Limit of detection is 5X10-7M. The plot of logarithms of selectivity coefficients vs. z/γ of various anions is essentially linear with a correlation coefficient of -- 0.88. Applications of the electrode in determination of total Cr in steels and copper alloys, and Cr(VI) in waste-water from chromium electroplating are reported.     

Construction and evaluation of a novel In(III) liquid ion-selective membrane electrode

A liquid ion-selective membrane electrode containing a chloroform-acetonitrile (10:1) solution of the complex of In(III) with 1-benzyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) and diphenylguanidine is described. The basic electrode performance characteristics were evaluated according to IUPAC recommendations. The slope of the calibration graph (electrode potential v. concentration) was 18.7 mV (pIn)(-1) in the pIn range 4.5-1 (pH 6). Direct potentiometric determination of In(III) showed an average recovery of 99.1% with a standard deviation of 1.2%. The method is recommended for the precise direct potentiometric assay of In(III) in metals and minerals without a prior separation.     

茜素S选择电极的研制和应用

本文报道了茜素S电极的研制和应用。比较了季铵盐、季鏻盐、碱性染料和邻二氮菲金属配合盐作为活性物质、各种介体溶剂以及活性物质在膜相中的含量对电极性能的影响。以三辛基甲基氯化铵制成的PVC膜型电极对茜素S在2×10~(-4)～5×10~(-7)M浓度范围内呈Nernstian响应,检测下限为2×10~(-7)M。测定了一些阴离子的选择系数,ClO_4~-,CNS~-,I~-以及能与茜素S配合的金属离子有明显干扰。报道了以茜素S电极为指示电极,用EDTA和茜素S为滴定剂滴定钪和稀土的情况。以茜素8电位滴定钪及钴-钐合金中的钐,都获得良好的结果。     

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。     

新型导电聚合物-聚吡咯溴离子化学传感器

本文用电化学方法把导电聚合物聚吡咯(PPy)修饰在玻碳(GC)电极上, 研究了Br^-离子的掺杂效应和薄膜电极的电化学行为, 研制一种新型Br^-离子选择电极, 电极的响应机制是基于导电聚合物中阴离子的掺杂效应, 详细研究了聚合条件对电极电位响应性能的影响, 电极具有内阻小、响应快、抗毒化能力强、制备简便等优点, 电极对1x10^-^1-x10^-^4MBr^-呈能斯特响应, 检测下限7x10^-^5M, 斜率61mV/PBr^-。本文结果是化学修饰电极技术在化学传感器方面应用的有意义的尝试, 薄膜的良好导电性质使之更易于制备离子敏感电子学器件和生物电子学器件。     

Chromium(III) ion-selective electrode based on 4-dimethylaminoazobenzene

A PVC-based membrane of 4-dimethylaminoazobenzene reveals a Nernstian potentiometric response (with slope of 19.5+/-0.6 mV/decade and a correlation coefficient of 0.999) for Cr(III) over a wide concentration range (1.66 x 10(-6)-1.0 x10(-2) mol dm(-3)). The potential of this electrode is independent of pH in the range of 3.0-5.5. It has a fast response time of about 10 s and was used for a period of 3 months with good reproducibility. The detection limits of this membrane electrode was 8 x 10(-7) M. the proposed electrode has been used as an indicator electrode in the potentiometric titration of Cr(III) with EDTA. This sensor exhibits a very good selectivities for Cr(III) over a wide variety of metal ions.     

功能高分子膜离子选择电极研究VI.压片PVC膜氯离子选择电极的暂态极化行为

Both fast triangle-wave potential sweep method and fast square-wave potential sweep method have been applied to study transient behavior of the functional polymer membrane chloride electrode. On the basis of current-time curve and potential-time curve, the electrochem. parameters of the electrode were calculated successfully under various conditions. The characterization of the level of ion transfer has been made by means of electrochem. polarization resistance Rr which is related not only to the membrane composition and its shape (area etc.), but also to concentration of the chloride ions in solution The Rr values calculated from both methods are the same. Cl- in the concentration range of 10-4-10-1 mol/L showed linear relation between i and log c, where c is the concentration The slope is proportional to the membrane area.     

脂溶性酞菁钴(III)为载体的高选择性亚硝酸根PVC膜电极

以自制的4,4',4',4''-四特丁基酞菁钴(II)为原料合成二氯4,4',4',4''-四特丁基酞菁钴(III)。以此为载体制备PVC膜电极。该电极的电位选择性次序明显不同于Hofmeister次序, 其最佳 响应斜率为-52mV/pNO2^-, 线性范围为3×10^-^5～1×10^-^1mol.dm^-^3NaNO2。通过改变配合物轴向的配位阴离子, 用紫外-可见光谱法对电极的响应机理作了初步探讨。     

Lead(II)-selective electrode based on phenyl disulfide.

A PVC membrane electrode for lead ions based on phenyl disulfide as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of 29.3 +/- 0.7 mV/decade and a linear range of 2.0 x 10(-6)-1.0 x 10(-2) M for Pb(NO3)2. The limit of detection is 1.2 x 10(-6) M. It has a response time of 45 s and can be used for at least fifty days without any divergence in potential. The proposed membrane sensor revealed high selectivity for Pb2+ over a wide variety of other metal ions and could be used in the pH range of 3.5-6.3. The electrode was used as an indicator electrode in potentiometric titration of lead ions.     

A new selenite selective membrane electrode and its application

A new membrane ion selective electrode sensitive to selenite ion has been developed. The electrode consisted of 1,2-phenylenediamine selen complex PIS (piaselenol) as the active material, PVC or SR (silicon rubber) as membrane matrix and DBF (dibutylphtalate) as plasticizer. This electrode showed linear response for selenite ion in the 10(-5)-10(-1)M concentration range. The slope of the linear portion was 21 mV/10-fold change in selenite concentration. The effect of membrane composition and membrane thickness on electrode response was studied and the electrode which contains 2% PIS, 49% PVC and 49% DBF was found to be the most sensitive one to selenite. The slope of the electrode did not change for 2 months and the pH change did not affect the response of the electrode in pH range of 3-9. The interferences of SO(4)(2-), SO(3)(2-), S(2-), HPO4(2-), CI(-), Br(-), and I(-) are investigated and while no interference was observed for SO(4)(2-), SO(3)(2-), S(2-) and I(-), a very small interference was observed for CI(-) and Br(-). The selenium present in anodic slime is determined using this electrode.