Electrochemical sensor

An electrochemical sensor converts chemical information into an electrical signal through reactions at electrodes or changes at an electrode interface.

Working electrode: The electrode where the target electrochemical reaction or interfacial measurement occurs. Its surface is where the analyte produces the sensor’s measurable electrical response.
Electrochemical cell: A system of electrodes and an electrolyte in which chemical reactions and electrical charge transfer are coupled. Electrochemical sensors operate as measurement systems built around this arrangement.
Glucose meter: A portable device that estimates blood glucose concentration from an electrochemical test strip. It is a familiar example of an enzyme-based electrochemical sensor used in routine care.
Optical chemical sensor: A sensor that detects chemical species through changes in light absorption, emission, scattering, or other optical properties. It reads light rather than electrode current or potential, often enabling remote measurements.
Reference electrode: An electrode that maintains a stable, known potential for measurements in an electrochemical cell. It provides the potential baseline needed to interpret the working electrode’s signal.
Electrolyte: A substance that conducts ions when dissolved or molten, enabling charge transport in an electrochemical system. Its ionic conduction completes the sensor’s circuit and shapes interfacial behavior.
Ion-selective electrode: An electrode whose potential responds selectively to the activity of a particular ion in solution. Clinical analyzers use these sensors to measure ions such as sodium and potassium.
Semiconductor gas sensor: A gas detector that infers gas presence from changes in a semiconductor’s electrical resistance or conductivity. Its signal comes from conductivity changes in a solid, rather than a liquid-electrolyte electrode reaction.
Counter electrode: An electrode that completes the circuit by carrying current opposite to the working electrode. It supplies the current required for controlled measurements at the sensing electrode.
Electrode: An electrical conductor through which current enters or leaves an electrochemical system. Sensor electrodes provide the interfaces where chemical events become electrical measurements.

Linked from 7 pages