Electrochemical sensors

An optical or electrical transducer is used here as one component. Fibre optic cable sensor, thermal sensor, potentiometric or amperometric transducers can be used. Second component is a chemically selective layer. For the better selectivity, usage of enzymes in the chemical layer is preferred. An example for amperometric enzyme electrode is glucose electrode. A redox mediator layer also can be used which catalyzes the electrochemical reaction. In ultramicroelectrodes, amperometric electrodes are made on a microscale. Its thickness is smaller than the diffusion layer thickness. Carbon fibre is used for the construction of electrodes.