Alexander P W, Dimitrakopoulos T, Hibbert D B
Department of Physical Sciences, University of Tasmania, P.O. Box 1214, Launceston, Tasmania, 7250, Australia.
Talanta. 1997 Aug;44(8):1397-405. doi: 10.1016/s0039-9140(97)00011-8.
A multi-sensor cell containing a new photo-cured calcium ion selective electrode sensor is reported. Four membranes containing different components are prepared to determine the one with optimum selectivity and sensitivity. This is shown to consist of the N,N,N',N'-tetracyclohexyl-3-oxapentanediamide ligand (ETH 129) as the ionophore, 2-nitrophenyl octyl ether as the plasticiser and tetradodecyl ammonium tetrakis(4-chlorophenyl) borate as the lipophilic additive. The photo-curing process is applied after coating a thin membrane on a silver wire as substrate transducer to produce the calcium sensor. The curing process is demonstrated to be faster (1 min) than previous methods and does not require a nitrogen atmosphere for reproducible production of membrane response characteristics. Four sensors constructed with the identical optimum membrane are shown to function reproducibly in a multi-sensor flow-through cell using the steady-state mode of flow measurement, and an average calibration slope of 28.5+/-0.4 mV change per activity decade is observed over a log-linear concentration range between 0.01 and 10 mM. The sensor is also shown to respond to changes in pH. Hence, in the flow injection potentiometric mode, a constant carrier buffer composition of pH 8.3 is required for accurate potentiometric calcium determinations. The sensor is used to determine calcium in water samples by flow injection potentiometry. The accuracy of the electrode determination relative to atomic absorption spectroscopy was in the range 5-9% for three different water samples.
报道了一种包含新型光固化钙离子选择性电极传感器的多传感器池。制备了四种含有不同成分的膜，以确定具有最佳选择性和灵敏度的膜。结果表明，该膜由N,N,N',N'-四环己基-3-氧杂戊二胺配体（ETH 129）作为离子载体、2-硝基苯基辛基醚作为增塑剂和十四烷基四（4-氯苯基）硼酸铵作为亲脂性添加剂组成。在将薄膜涂覆在作为底物换能器的银丝上之后应用光固化工艺来制备钙传感器。事实证明，固化过程比以前的方法更快（1分钟），并且不需要氮气气氛即可可重复地产生膜响应特性。使用相同的最佳膜构建的四个传感器在采用稳态流动测量模式的多传感器流通池中可重复运行，并且在0.01至10 mM的对数线性浓度范围内观察到平均校准斜率为每活性十年变化28.5±0.4 mV。该传感器还显示出对pH变化有响应。因此，在流动注射电位法模式下，准确测定电位钙需要pH 8.3的恒定载体缓冲液组成。该传感器用于通过流动注射电位法测定水样中的钙。对于三种不同的水样，相对于原子吸收光谱法，电极测定的准确度在5-9%的范围内。
