带有旋转圆盘电极的流通检测池及其在流动注射电位溶出分析中的应用

A Flow Cell With a Rotating Disk Electrode for Flow Injection Potentiometric Stripping Analysis

制作了一个带有旋转圆盘电极的流通检测池,并对其作了评价。流通池内由于电极旋转提高了有效传质,从而提高了信号响应灵敏度,而且即使在低流速下也不会降低灵敏度。当电极转速大于810rpm 时,流速对信号的影响相对于转速的影响几乎可以忽略。将该检测池应用于流动注射电位溶出分析体系,结果表明,检测池非常适合于流动系统的电位溶出分析,并且其检测限比静止电极的 Wall-jet 检测池提高一个数量级。

A flow cell with a rotating glassy-carbon disk electrode is described and eva- luated by timing amperometry.The work shows that supplementary forced convection(rota- tion in our case)is to enhance the rate of mass transport.The sensitivity is increased considerably,and the response is independent on the flow rate at rotation speeds over 810 rpm.As a result,low flow rates can be used without sacrificing the sensitivity.Analy- ticat advantages are demonstrated using flow injection potentiometric stripping analysis. The results show that the flow cell is very suitable for potentiometric stripping analysis in flow system,and its detection limit is lower than Wall-jet detector's by one order of magnitude.