Muchun Zhong, a member of Steffi Krause's group, has developed a novel, effective way for detecting zinc ions with a potentiometric sensor.

The zinc ion is among the most abundant trace metal ions in the human body, which is intimately involved in a wide range of physiological and pathological processes. Variation in the concentration of cellular zinc is associated with a number of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, whilst dietary zinc supplementation has been reported to slow down the progression of age-related macular degeneration that can cause blindness.

By chemically binding a zinc chelator to the surface of a light-addressable potentiometric sensor (LAPS) in a single self-assembled monolayer, Muchun's development achieved a simplified sensor surface with excellent reversibility and selectivity. In contrast to the polymer membranes traditionally employed in ion-selective sensors, the ultrathin sensor layer used in this work exhibits a high signal-to-noise ratio and remains resistant to membrane leaching and degradation.

As LAPS are imaging sensors, this sensor technology has the potential of label-free imaging of extracellular zinc ion concentrations in cell culture and organ-on-chip devices with high spatial resolution in the future.

The work has been accepted by Sensors and Actuators B: Chemical and is available to read on the website.