In this study, a fluorescence azothiazol-benzenesulfonamide derivative (M-sensor) was prepared for the determination of Mg 2+ ions in different samples. The utilized M-sensor exhibited an emission fluorescence activity at 587 nm upon excitation at 537 nm. The developed method was based on the quenching effect of Mg 2+ ions on

Selective fluorometric detection and determination of uranium ions is provided here using a novel fluorescent reagent, namely (E)-4-([4-hydroxynaphthalen-1-yl]diazenyl)-N-(5-methyleisoxazol-3-yl) benzenesulfonamide (U VI reagent). The U VI reagent offers a selective fluorescence enhancement behaviour at emission wavelength = 557 nm. The parameters affecting fluorometric detection of uranium ions, such as the pH, solvent type, ligand concentration, interaction time, and interfering ions, were investigated and adjusted. The proposed U VI reagent can detect and determine uranium ions even at low concentrations, for which the obtained limit of detection was 0.1 ppm. Additionally, this proposed determination protocol was successfully used to detect, monitor, and determine uranium ions in actual water samples.