以1,1′-联萘并-20-冠-6为载体的钾离子选择电极

Potassium Ion-Selective Electrode Based on 1,1′-Binaphthyl-20-crown-6

报道了1,1′_联萘并_20_冠_6为钾离子载体的聚氯乙烯 (PVC)膜电极的研制 ;研究了电极膜中增塑剂种类及载体和离子定域体 (KTpClPB)含量对电极性能的影响 ;得到了电极膜中各组分的最佳质量比为w(载体)∶w(PVC)∶w(DOS)∶w(KTpClPB)=1.6∶32.5∶65.0∶0.9 ;该选择电极对钾离子有良好的能斯特响应性能和高选择性 ,线性响应范围为10 -4～10 -1mol/L ,斜率为58.1mV/p +Kc ;电极具有优良的重现性和较宽的 pH使用范围 ;将该电极用于药品中钾离子含量的测定 ,其结果与原子吸收法一致。

This paper reports a new potassium ion-selective electrode with polyvinyl chloride membrane using 1,1′-binaphthyl-20-crown-6 as the ionophore. The effects of various plasticizers and amounts of the incorporated ionophore and ionic additive(KTpClPB) on the response characteristics were studied. The electrode containing 1.6% ionophore, 32.5% PVC, 65.0% DOS and 0.9% KTpClPB was found to have the best performance towards K+. The K+-PVC electrode exhibits good Nernst response characteristics and fairly good selectivity towards K+. Its linear response range is 10-4～10-1 mol/L, and the corresponding slope is 58.1 mV·decade-1. The electrode has the advantages of good stability, repeatability and wider pH range. It can be used for the determination of K+ in potassium penicillin-V tablets. The results obtained by this method are in agreement with those from atomic absorption spectrophotomertic analysis.