A murexide-functionalized UiO-66 (Zr) MOF was synthesized through post-synthetic immobilization to facilitate the detection of Zn 2+ ions in aqueous environments using a triple-mode approach. This sensor exhibits a noticeable color change observable to the naked eye from pink to colorless, a UV–Vis response at a wavelength of 517 nm, and a fluorescence “turn-on” emission at 424 nm λ_ ex = 360 nm. Under optimized conditions (pH 7, 0. 5 mg sensor per 10 mL solution, and a response duration of 30 s), the limits of detection were established at 0. 034 ppm for UV–Vis measurements and 0. 007 ppm for fluorescence. The material displayed a significant selectivity for Zn 2+ over 14 competing ions, maintaining over 85% of its signal after six regeneration cycles and retaining approximately 90% of its response after six months of storage. The sensor's practical applicability was demonstrated in the analysis of tap water and wastewater, yielding recoveries ranging from 98. 5% to 101. 1%, which correlated well with results obtained from ICP-OES. • A Mur-Zr MOF sensor was fabricated by grafting murexide onto NH₂-UiO-66 (Zr). • The sensor exhibits triple-mode detection: colorimetric, UV–Vis, and fluorescence. • High sensitivity achieved with LODs of 0. 52 μM (UV–Vis) and 0. 18 μM (fluorescence). • Excellent selectivity, reusability (≥6 cycles), and stability (30 days) were demonstrated. • Real-sample validation in water and human serum showed recoveries of 94. 8–103. 5%.
Roaa T. Mogharbel (Tue,) studied this question.