Phosphate (Pi) and superoxide anion radical ( \({\text{O}}_{2}^{\cdot -}\) ) serve as crucial bioactive molecules, with their dysregulated concentrations being strongly implicated in the pathogenesis of multiple disorders, including atherosclerosis and neurodegenerative diseases. This study innovatively developed a dual-functional fluorescent sensor, UiO-66-NH₂@CDs, which achieved high-selective simultaneous detection of Pi and \({\text{O}}_{2}^{\cdot -}\) for the first time. A mild room-temperature stirring method was used to construct the amino-functionalized UiO-66-NH₂ carrier, followed by post-synthesis modification to precisely load fluorescent carbon dots (CDs) specific for superoxide anion recognition. Mechanism studies revealed that the redox reaction between CDs and \({\text{O}}_{2}^{\cdot -}\) specifically activates the fluorescence signal at 655 nm, while the Zr (IV) clusters in UiO-66-NH2 form Zr-O-P coordination bonds with Pi, leading to fluorescence recovery at 440 nm. The detection limit for Pi was 0.032 μM, and for O2⋅− was 0.21 μM, with no interference between two detection channels. In actual serum sample testing, the recovery was 97.2%-104.8%, with a relative standard deviation < 3.8%, confirming the reliability of this method in complex matrices. This study provided a novel analytical tool for exploring the synergistic mechanisms of Pi and \({\text{O}}_{2}^{\cdot -}\) in physiological and pathological processes.
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