Detection of glutathione and Fe3+/Hg2+ ions in living cells with a water-soluble fluorescent probe

Fluorescein-(S)-2-ammonio-3-phenylpropyl S )-2-ammonio-3-phenylpropyl sulfate (FAPS) as a fluorometric and colorimetric chemosensor was designed and mechanochemically synthesised to quickly identify glutathione in comparison to homocysteine and cysteine in aqueous medium with a LOD 153 nM. The FAPS also detected Hg2+ 2 + and Fe3+ 3 + ions in an aqueous medium by quenching the absorbance intensity at lambda max 455 and 460 nm, respectively. . However, the UV-visible signals of FAPS-Hg2+ 2 + and FAPS-Fe3+ 3 + complexes were distinguishable upon the addition of EDTA. When using water as the solvent, this probe demonstrated shorter incubation times than the contemporary ones in the literature. Even at 20 M FAPS concentrations, no cytotoxicity was observed. Additionally, the probe accurately identified and measured the levels of GSH, as well as Fe3+, 3 + , and Hg2+ 2 + ions in lung cancer cell lines. The fluorescence quantification of FAPS was measured at 5.0 mM for GSH, 0.36 mM for Fe3+, 3 + , and 10.0 mM for Hg2+ 2 + ion, though the Hg2+ 2 + ion has shown the largest difference among the three species. Overall, the synthesis of this probe with dual functions may save time and expense compared to making two separate sensors for sensing biothiols and metal cations.