A multifunctional metal–organic complex fluorescent probe for highly sensitive detection of lysine, CrO42-/Cr2O72-, Fe3+ and nitro-aromatic compounds

Water contamination caused by organic and inorganic compounds represents an urgent global issue. It is meaningful to detect these compounds. A metal–organic complex (Zn-HTBA) was investigated as a multifunctional fluorescent probe which showed exceptional fluorescence characteristics. The Zn- HTBA can specifically detect lysine in water through fluorescence enhancement, and the detection limit was 0.17 μM. The Zn-HTBA also selectively detect CrO42-/Cr2O72- and Fe3+ with the detection limits of 0.014/0.022 and 0.12 μM through fluorescence quenching. In addition, the Zn-HTBA was found to sensitively detect nitroaromatic compounds in ethanol through fluorescence quenching. The possible detection mechanisms were studied in detail through UV–Vis, PXRD, XPS, etc. The mechanism of Zn-HTBA to detect CrO42-/Cr2O72-, Fe3+ and 2-nitrotoluene was energy competition, and the mechanism of Zn-HTBA to detect lysine was the formation of hydrogen bonds. © 2024 Elsevier B.V.