Zinc-based metal-organic frameworks as fluorescent probes for the detection of Vitamin B6

Vitamin B6 (VB6) is a water-soluble vitamin, which plays an important role in amino acid metabolism and cell maintenance as a coenzyme of amino conversion. Developing a highly sensitive and selective sensor for VB6 is still a huge challenge. Herein, a luminescent Zn-MOFs (ZnL) with the ligand 4,4'-(1H,1 ' H-[2,2 '-biimidazole]-1,1 '- diylbis(methylene)) dibenzoic acid (H2L) was designed for analyzing VB6. The presence of uncoordinated N atoms in ZnL can provide action sites for VB6 molecule, therefore, ZnL can be applied to specific detection of VB6 molecule. ZnL exhibits a strong emission spectrum at 390 nm when excited at 300 nm, which realizes the fluorescence quenching detection of VB6 in aqueous solution. Furthermore, the detection of VB6 with high sensitivity and selectivity can be obtained even in the presence of common biomolecules. The linear range for VB6 detection was observed in the concentration range from 5 to 100 mu M with a low limit of detection of 0.76 mu M. Hence, ZnL has promising application potential for determination of VB6 in practical applications.