新型中性载体水杨酸根离子选择性电极的研究

由于水杨酸在医药及化妆品等方面广泛应用,其使用过量又会造成极大危害,因此,设计一种性能优异的水杨酸根离子选择性电极具有重要的意义。本文研制了一种以水杨醛缩1,3-丙二胺合铜(Ⅱ)(Cu(Ⅱ)-Schiff])为中性载体的PVC膜阴离子选择性电极,采用电化学方法对其性能进行表征,选用紫外光谱研究了该电极对Sal-的响应机理,并将电极初步应用于实际样品分析。结果表明:此电极对Sal~-具有较好的电位响应,其在pH=5.0的磷酸盐缓冲体系中性能最佳,响应范围为1.0×10~(-1)~1.0×10~(-6)mol/L,检测下限为2.3×10~(-7)mol/L,斜率为-59.6 mV/dec,响应时间为t_(9596)为17 s,电极具有至少2个月的使用寿命,该电极用于阿司匹林及复方阿司匹林药片中水杨酸的测定是可行的。因此,本实验设计的离子选择性电极在测定药片里水杨酸含量方面具有一定的应用前景。

Study on Selective Salicylate Electrode Based on a Novel Neutral Carrier

The excess use of salicylic acid,used widely in medicine and cosmetics,could cause great harm,so designing a kind of excellent salicylic ion selective electrode would have the vital significance.This article selected N,N＇-bis （salicylidene）-l,3- propanediamine copper （II） Schiff base complex（Cu（II）-Schiff]） as neutral carrier used in the study of PVC membrane anion selective electrode.Its performance was characterized by electrochemical methods and means,the electrode response mechanism was investigated by ultraviolet spectrum,and it was applied to detect actual samples preliminarily：The result showed that the electrode exhibits a near Nernstian response for Sal- over a wide concentration range（1.0×10-1-1.0×10-6 mol/L） with a slope -59.6 mV per decade and a detection limit of 2.3×10-7 mol/L in a pH range of 5.0.h has a fast response time of about 17 s. The electrode had been applied to the determination of aspirin and compound aspirin tablets with satisfactory results.Therefore, the ion-selective electrode designed has a certain application prospect in the aspect of salicylic acid content determination in the tablets.