Solvent-processible polymer membrane-based liquid junction-free reference electrode
Solvent-processible polymer membrane-based liquid junction-free reference electrode
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DOI：
10.1021/ac980265k
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发表时间：
1998-08-15
影响因子：
7.4
通讯作者：
Cha, GS
中科院分区：
文献类型：
--
作者：
Lee, HJ;Hong, US;Cha, GS
采用溶剂可加工的聚合物膜设计了一种新型的液接自由参比电极系统。该膜以单组分硅橡胶或芳香族型聚氨酯为基体配制而成。优化的配方包含阳离子和阴离子交换位点（即，四（对氯苯基）硼酸钾和三（十二烷基）甲基氯化铵）;在硅橡胶的情况下，增塑剂。硅橡胶为基础的膜，而对大多数离子具有最小的响应，被发现显示近能斯特响应pH值的变化。然而，芳族聚氨酯基质制剂在宽范围（即pH 2-12）内对pH不敏感，并且显示出即使在非常高的浓度（即高达0.1M）下，对于所添加的各种各样的盐也仅表现出小的电动势变化（在+/-2mV内）。ISE（例如，Na+，K+，Ca 2+，Cl-）的电位电动势响应，无论是与聚合物膜为基础的参比电极或与传统的液体连接型参比电极配对，被证明是非常相似的精度内的测量设置。适应所提出的参考电极的平面固态传感器格式的可行性也被证明。
A new type of liquid junction;free reference electrode system is devised by employing solvent-processible polymer membranes. The membranes are formulated with either a one-component silicone rubber or an aromatic-type polyurethane as the matrixes. The optimized formulations incorporate both cation- and anion-exchange sites (i.e,, potassium tetrakis(p-chlorophenyl)borate and tridodecylmethylammonium chloride) and; in the case of silicone rubber, a plasticizer. The silicone rubber-based membrane, while possessing minimal response toward most ions, is found to display a near-Nernstian response to pH change. The aromatic polyurethane matrix formulation, however; is not sensitive to pH over a wide range (i.e,, pH 2-12) and is shown to exhibit only a small emf variation (within +/-2 mV) toward a wide variety of salts added even at very high concentrations (i,e,, up to 0.1 M). Potentiometric emf responses of ISEs (e.g,, Na+, K+, Ca2+, Cl-), whether paired with a polymer membrane-based reference electrode or with a conventional liquid junction-type reference electrode, are shown to be remarkably similar within the precision of the measurement setup. The feasibility of adapting the proposed reference electrode to the planar solid-state sensor format is also demonstrated.