Pyrazine-Functionalized Bio-MOFs for Selective Luminescence Sensing of Colchicine and Nitrofurazone in Aqueous Solutions

By employing a mix-linker strategy, we have successfully synthesized two isostructural anionic microporous biological metal-organic frameworks (Bio-MOFs), showing excellent chemical stability across a pH range of 3-14 in the aqueous phase. Luminescence titration studies reveal that replacing the benzene core of the carboxylate linker with pyrazine leads to markedly enhanced energy transfer from the linker to the metal cluster, significantly increasing the emission intensity. This linker engineering strategy endows the MOF with superior performance in antibiotic sensing with limits of detection of 1.5 μM for colchicine (COL) and 0.8 μM for nitrofurazone (NFZ). Additionally, the title MOF exhibited selective detection of COL and NFZ in the presence of potential interfering species, including other antibiotics or serum species. Moreover, a mixed matrix film was fabricated by dispersing the MOF crystalline powders on a polycaprolactone sheet, demonstrating real-time on-site monitoring of COL and NFZ in aqueous solutions.