Real-time monitoring of inhibitory effects on glutamate-induced neurotransmitter release using a potassium ion image sensor

To directly image the release of neurotransmitters from neurons, we combined a substance-selective layer with a 128 × 128–pixel ion image sensor based on CMOS technology. Using the substance-specific image sensors, we studied the dynamics of potassium ion (K+) release from neurons and examined the effect of ouabain on K+ release. K+ transients were significantly inhibited by ouabain. The K+ image sensor used in this study demonstrated the dynamic analysis of ligand-operated signal release and the pharmacological assessment of secretagogues without requiring cell labeling.