Design, Synthesis, and Characterization of pH-Resettable Photoswitches Mimicking the GFP Fluorophore Structure

• DOI: 10.1021/acs.jpcb.4c07003
• Publication Date: 2025-03-06T15:48:25Z
• Authors: Nicola Ferrara; Germano Giuliani; Marios Maimaris; Salvatore Prioli; Madushanka Manath...; Lluís Blancafort; Jérémie Léonard; Andrea Cappelli; Massimo Olivucci; Marco Paolino
• Keywords: Characterization

Light-controlled molecular switches based on double bond isomerization can represent classical binary systems in logic gates. Here, starting from the biomimetic photoswitch 1 and combining computational experimental techniques, we designed insertion of a third control element (the "reset button"), proposing an appropriate structural modification capable altering electronic distribution within molecule. Thus, substitution pyrrolidinone nitrogen atom with methane sulfonic (in 2a) or toluene 2b) functional groups furnished molecules alternating between two stable equilibrium forms by light irradiation. The addition KOH deprotonates phenolic moiety photoswitches, providing which Z isomer becomes thermally unstable spontaneously evolves into E isomer. Re-establishing initial form (e.g., acetic acid), re-establish both isomers relative stability their photochemical properties. These prototype potentially pH-resettable possible applications pH-sensitive organic materials.