Basic-to-acidic reversible pH switching with a merocyanine photoacid

Journal article, 2022

The application of merocyanine photoacids has previously been largely limited to neutral and acidic pH values. Here we introduce a new merocyanine photoacid with superior pH switching qualities. By increasing the pK(a) in the dark (pKdark(a)) and the solubility we increased the reversible visible light induced pH jump to 3.5 units. Moreover, it is the first demonstration of a merocyanine photoacid able to generate a significant pH drop from a basic (pH 8.3) to an acidic (pH 5.2) environment.