Dual-Emitting Eu(III)-Cu(II) Heterometallic-Organic Framework: Simultaneous, Selective, and Sensitive Detection of...

As important biomolecules, the deficiency or maladjustment of hydrogen sulfide (H₂S) or ascorbic acid (AA) is associated with the symptoms of the same disease (e.g., cardiovascular disease or cancer). There is an urgent need to develop a fluorescent probe capable of distinguishing between H₂S and AA simultaneously. Here, we report the syntheses, structure, and property of the first dual-detection fluorescent probe which can differentiate H₂S or/and AA in aqueous media. Accordingly, a novel [EuCu(pydc)₂(ox)_0.5(H₂O)₃·1.5H₂O]_{2 n} (1, H₂pydc = 2,3-pyridinedicarboxylic acid and ox = oxalic acid) for selective and sensitive detection of H₂S and AA in a wide range has been constructed (H₂S: [130 nM, +∞); AA: [55 nM, +∞)), exhibiting excellent catalytic activity comparable to horseradish peroxidase. In addition, the highly efficient detection in human serum sample also proves the potential application in medical diagnosis. Meanwhile, a combinatorial logic gate (AND(INH)-OR) based on activated 1 has also been constructed. Furthermore, this approach for simultaneous H₂S and AA detection suggests that the current work will expand the potential application of metal-organic frameworks for dual or multiple detections in biomedical fields.