Gupta Vinod Kumar, Goyal Rajendra N, Agarwal Shiva, Kumar Pankaj, Bachheti Neeta
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttaranchal, India.
Talanta. 2007 Feb 15;71(2):795-800. doi: 10.1016/j.talanta.2006.05.036. Epub 2006 Jul 5.
Nickel(II)-selective sensors have been fabricated from poly(vinyl chloride) (PVC) matrix membranes containing neutral carrier dibenzo-18-crown-6 as electroactive material, sodium tetraphenylborate (NaTPB) as an anion excluder and tris-(2-ethylhexyl) phosphate (TEHP) as plasticizing solvent mediator. The membrane having the composition of crown ether:NaTPB:TEHP:PVC in the ratio 10:1:200:200 (w/w) exhibits best results with linear potential response in the concentration range of 1.0x10(-5) to 1.0x10(-1)M and a Nernstian slope of 29.5mV/decade of activity between 2.6 and 6.8. The sensor exhibits a fast response time of <25s, is inert towards non-aqueous medium up to 15% (v/v) and was used over a period of 4 months with good reproducibility. It is selective over a number of mono-, bi- and trivalent cations. The practical utility of the sensor has been demonstrated by using it as an indicator electrode in the potentiometric titration of Ni(2+) against EDTA and also for the estimation of Ni(2+) in some Indian brand chocolates.
已用含有中性载体二苯并 - 18 - 冠 - 6作为电活性材料、四苯硼酸钠（NaTPB）作为阴离子排除剂以及磷酸三（2 - 乙基己基）酯（TEHP）作为增塑溶剂介质的聚氯乙烯（PVC）基质膜制备了镍（II）选择性传感器。冠醚：NaTPB：TEHP：PVC的组成比例为10:1:200:200（w/w）的膜表现出最佳结果，在1.0×10（-5）至1.0×10（-1）M的浓度范围内具有线性电位响应，在2.6至6.8之间的活度每十倍变化时能斯特斜率为29.5mV。该传感器响应时间<25秒，对高达15%（v/v）的非水介质呈惰性，并且在4个月的时间内使用具有良好的重现性。它对多种单价、二价和三价阳离子具有选择性。通过将其用作指示电极，在以EDTA电位滴定Ni（2+）以及在一些印度品牌巧克力中测定Ni（2+）时，已证明了该传感器的实际用途。
