Highly efficient Ca 2+ chelation activated by visible light.

Calcium ion (Ca 2+ ) control is an essential tool in neuronal research. Herein, we report three thiocoumarin-based, visible light-activated Ca 2+ chelators with quantum yields of 0.39, 0.52, and 0.83. The chelators demonstrated an over 10 5 -fold increase in Ca 2+ binding affinity upon irradiation. These chelators are efficiently triggered by biologically safer wavelengths, rendering them excellent candidates for use in neurological research and medicine.