Efficient acetate sensor in biological media based on a selective Excited State Proton Transfer (ESPT) reaction

[Display omitted] •“On/off” fluorescent dye to detect acetate.•High sensitivity Acetate detection in biological serum is reported.•Acetate ions are relevant in physiological processes because it participates directly and/or indirectly in cancer metabolism. We have synthesized a new fluoride−containing xanthenic dye able to dynamically and quantitatively detect acetate anion, a biologically relevant analyte, in water. We studied deeply the photophysical properties of the compound and verified its use as an acetate probe in synthetic serum.