Abstract

Selective electrodes for the detection of ions in liquids such as human body fluids or environmental waters are highly sensitive and selective analytical tools that offer a variety of advantages, such as simplicity of measurement, high analysis throughput, rapid detection, continuous on-line monitoring, and low cost of analysis. While such sensors are used in clinical laboratories for billions of measurements every year, applications in biomedical sciences, the food industry, and environmental monitoring have been hindered by sensor fouling and the frequent need for recalibration. This talk will first give an overview of the underlying principles, capabilities, and limitations of ion-selective electrodes. It will then turn to the challenges and opportunities that motivate ongoing research, which include (1) long-term sensor stability, (2) calibration-free measurements, (3) miniaturization and low-cost design for point-of-care analysis, and—in view of long-term monitoring in the human body and the environment—(4) robust design and resistance to chemical and biological fouling.