Dual-ligand Zr-based metal-organic framework probe with turn-on fluorescent response for dual-channel live cell imaging of phosphate and glutathione.

In diseases associated with oxidative stress, such as chronic renal failure, alcoholic liver disease, and hyperthyroidism, both phosphate and reduced glutathione (GSH) levels significantly deviate from the normal physiological range. Therefore, simultaneous monitoring of phosphate and GSH levels is of great clinical significance for disease diagnosis and prognosis. Herein, an innovative dual-detection fluorescent probe constructed on a dual-ligand engineered Zr-based metal-organic framework (Zr-MOF) platform is introduced. This probe is designed for the simultaneous detection of phosphate and glutathione (GSH). Specifically, Cu(II) acts as a non-framework metal, coordinating with tetrakis(4-carboxyphenyl) porphyrin (TCPP) to enable specific recognition of GSH, while Zr(IV) serves as the framework node, detecting phosphate through coordination with phosphate anions. The synergistic effect of the two ligands enables dual detection, achieving a detection limit of 3.24 µM for phosphate and 2.81 µM for GSH, with a wide linear range of 0-100 µM. Rigorous interference tests confirmed that the signal retention rate exceeds 90% in the presence of competitive biomolecules. Benefiting from its small particle size and excellent water solubility, the probe can be applied to live-cell imaging technology, successfully enabling real-time tracking of exogenous phosphate uptake processes and dynamic GSH fluctuations in HeLa cells. This work provides a promising tool for the diagnosis and prognosis of the aforementioned diseases.