PVC膜氟离子选择性电极的研制及应用

Development and application of PVC membrane fluoride ion selective electrode

以氟硼酸钠与四苯硼酸钠生成的电活性物质合物质为载体,研制了一种对氟离子具有选择性响应的PVC膜离子选择性电极。结果表明:当电活性物∶PVC∶邻苯二甲酸二甲酯=3.3∶27.6∶69.1(w/w)时,电极具有最佳的电位响应特性,氟离子浓度在1.0 mol·L^-1~3.2×10^-5 mol·L^-1范围内呈能斯特响应,斜率为40.7mV/dec,响应时间30s左右,检测下限为6.3×10^-6 mol·L^-1,将该电极用于牙膏中氟含量测定,结果与PF-1型氟离子电极测得值基本一致。

A PVC membrane ion selective electrode with selective response to fluoride ion is developed by using an electroactive material formed by sodium fluoborate and sodium tetraphenylborate as carrier.Results show that the electrode has the best potential response characteristics when electroactive material∶PVC∶dimethyl phthalate=3.3∶27.6∶69.1(w/w),the electrode has the best response characteristics,when the concentration of fluorine ion is in the range of 1.0 mol·L^-1-3.2×10^-5 mol·L^-1.The slope of electrode is 40.7 mV/dec,the response time is approximately 30 seconds and the detection limit is6.3×10^-6 mol·L^-1.The results of using the electrode to determine fluoride content in toothpaste are basically consistent with that measured by PF-1 fluoride ion electrode.