Monitoring Fluorescence Response of Amphiphilic Flapping Molecules in Compressed Monolayers at the Air–Water Interface

Abstract

The air-water interface, which is the boundary of two phases with alarge difference in polarity, gives adistinct environmentc ompared with bulk water or air.S ince the interface provides af ield for various biomolecules to work, it is importantt ou nderstand the molecular behaviors at the interface. Here, polarity-independentf lapping viscosity probes (FLAP) equipped with hydrophobic/hydrophilic substituents have been synthesized and studied at the airwater interface. In situ fluorescence( FL), which is related to the internal motion and orientation, of three different FLAPs were investigated att he interface, and the internal motion of the molecule was indicated to be suppressed at the interface. In addition, the molecular response was compared with that of conventional viscosity probes (molecular rotors), which indicatest he different behaviors of FLAP probably due to the distinct molecular orientation as wella sm olecular motion.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

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