基于中性载体的PVC膜锂离子选择电极的研制

Lithium Ion-selective PVC Membrane Electrode Based on Neutral Ionophore

本文报道一种基于中性载体的PVC膜锂离子选择电极,采用两种增塑剂和不同量的阴离子定域体对电极膜进行优化,考察了影响电极响应和电极稳定性的一些主要因素。其中以含1.0%ETH1810、0.2%KTpClPB、66.0%2—NPOE和33.0%PVC的膜组成制备的电极在pH8.0的0.05mol/L Tris-HCl缓冲溶液中对锂离子呈良好的Nernst响应,斜率为56.0mV/decade,线性响应范围为3.2×10^(-5)—1.0×10^(-1)mol/L,检测下限为1.6x10^(-5)mol/L,电极具有很好的稳定性和重现性,对Na^+和K^+的选择性系数K(?)分别为:5.0×10^(-3)、3.2×10^(-3)。加标回收方法测试血清样品,说明了临床分析应用的可能性。

The PVC membrane lithium ion-selective electrodes based on lipophilic neutral carrier ETH1810 were prepared. The membrane composition was optimized by variation of the content of anion site KTpClPB. A membrane containing 1. 0% ETH1810, 0. 2% KTpClPB,33. 0%PVC and 66. 0% 2-NPOE was obtained. The slope of the electrode was 56. 0 mV/decade, with the linear range of 3. 2×10-5-1. 0×10-1mol/L and the detection limit of 1. 6×10-5mol/L. The electrode showed moderate selectivity for Li+ over Na+ and K+. The other characteristics of the electrode were also satisfactory. It is possible to use the electrode to assay Li+ in blood within the clinically relevant concentration range or in other real samples why flow injection analysis.