A novel spectrofluorimetric method based on a reaction with an azoisoxazoles-benzenesulfonamide derivative for determination of uranium (VI) ions in water samples.

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 (UVI reagent). The UVI 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 UVI 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.

Spectrofluorimetric determination of magnesium ions in water, ampoule, and suspension samples using a fluorescent azothiazol-benzenesulfonamide derivative.

In this study, a fluorescence azothiazol-benzenesulfonamide derivative (M-sensor) was prepared for the determination of Mg2+ 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 Mg2+ ions on the fluorescence intensity of the M-sensor with the above-mentioned fluorescence features. Furthermore, the utilized M-sensor was complexed with Mg2+ ions in the molar ratio of 1:1 (Mg2+ to M-sensor) and the selectivity of M-sensor toward Mg2+ against other metals ions, and the reversibility and reusability of the sensor were studied and verified. After optimization of the fluorometric detection, the quenching effect was directly proportional to the increase in the concentration of Mg2+ in the linear range 100-600 ng ml-1 with a limit of detection value of 18 ng ml-1 . The fluorescence sensor was successfully applied with good recovery for the determination of Mg2+ in water samples and different pharmaceutical samples (ampoules and suspension) without any interference from aluminium.