AAQ chloride

This photoswitchable small molecule acts as a light-dependent potassium channel blocker, with higher potency in its cis-form induced by 500 nm light (IC50 = 2 μM) compared to its trans-form at 380 nm (IC50 = 64 μM) . It enables precise optical control of neuronal excitability, demonstrated by stimulating hippocampal neuron firing in vitro and restoring visual responses in vivo in blind mouse models.