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HIGH SCHOOL

Chemistry

Concept Videos

Analytical Chemistry

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Electrochemical Analyses and Redox Titration

Measuring Analytes with Amperometric Sensors

Description

Amperometry measures specific analytes in a solution by tracking the electric current from an electrochemical reaction. A constant potential is applied between a working electrode and a reference electrode. The current that results is proportional to the analyte concentration.

The Clark oxygen el...

Transcript

安培法是一种电分析方法,通过在恒定电位下测量电极上产生的电流来实现分析。

产生的电流与分析物的浓度成正比,从而实现对其的检测和定量。

安培法用于化学传感器的构建。

例如,L. C. Clark 开发了第一种安培传感器,用于测量血液中溶解氧的浓度。该传感器封装在一层透气膜内,包含一个铂阴极和一个银-氯化银阳极,并以氯化钾溶液作为电解质。

当在阴极和阳极之间施加电压时,溶解的氧气分子会穿过膜并在阴极表面发生还原反应。阳极为此反应提供电子,产生与样品中氧气浓度成正比的电流。

安培法也用于葡萄糖生物传感器中,以监测血糖水平。