Innovative covalently modified Al‐MOF as a highly selective fluorescent sensor for Al (III) detection in tap water, human serum, and tea samples

Abstract

Generally, aluminum exposure is not a risk; however, long‐term and high‐intensity exposure can have a negative impact on health. The ligand‐embedded MOF was developed for high sensitivity in the detection and removal of Al (III) ions in aqueous solutions. Novel selective metal–organic framework was synthesized via strong covalent attachment of NH2‐MIL‐53(Al) and 2‐hydroxy naphthaldehyde (2‐HNA) for selective and efficient fluorometric sensing of Al (III) ions. The elemental structure and morphology of the fabricated sensor (2‐HNA = N‐MIL‐53[Al]) were thoroughly evaluated to understand the high selectivity and considerable fluorescence stability in the water. The intensity of the sensor fluorescence increased linearly as the concentration of Al (III) increased from 0.19 to 2.0 ppm with a detection limit of 33.1 ppb (1.23 × 10−6 M) and 5 s of response time at pH 7. The potential mechanism is discussed. The high selectivity of the developed chemosensor was achieved against various competing environmentally relevant metal ions. Furthermore, Al (III) ions were successfully quantified in tap water, wastewater, human serum, and tea samples. The high precision (RSD percent, 0.009–1.76) and excellent accuracy (recovery percent, 99.96–101.56) of the 2‐HNA = N‐MIL‐53 (Al) sensor indicated that it holds great promise for the ultrafast and highly selective determination of Al (III) ions in wastewaters, with high reproducibility and reversibility.