Ion Selective Electrodes (ISEs) are analytical devices used to measure the concentration of specific ions in a solution. They work by generating a voltage that corresponds to the ion activity, allowing for precise quantification. ISEs are commonly used in various fields, including environmental monitoring, clinical diagnostics, and food safety. These electrodes consist of a sensing element, typically made from a selective membrane, that interacts with the target ion. The response of the electrode is influenced by factors such as temperature and ionic strength, making calibration essential for accurate measurements.