Zinc(II) organic framework based bifunctional biomarker sensor for efficient detection of urinary 5-Hydroxyindoleacetic acid and serum 3-Nitrotyrosine.

Monitoring biomarker levels in body fluids is of great importance in clinical diagnosis. Herein, a robust 3D ZnMOF, {[Zn₂(BTPB)_0.5(bib)_1.5(μ₂-OH)]·2H₂O}_n, was fabricated based on the ligands of 1,4-bis(2,4,6-tricarboxylpyrid-5-yl)benzene (H₆BTPB) and 1,4-bis(imidazol-1-yl)benzene (bib). On the basis of its stable architecture and intrinsic luminescence, ZnMOF demonstrated remarkable potential as a bifunctional luminescent sensor for selective and sensitive detecting the biomarkers of 3-nitrotyrosine (3-NT) and 5-hydroxyindoleacetic acid (5-HIAA) in water and body fluids by employing distinct "turn-off" and "turn-on" responses. Additionally, the inherent sensing mechanism was further assessed from the viewpoints of spectral overlap and photo-induced electron transfer. This work manifested MOFs-based luminescent sensors are developing into an effective method for detecting biomarkers in body fluids with perfect practicality and compatibility.