Dual-Emitting Mixed-Lanthanide Metal-Organic Framework for Ratiometric and Quantitative Visual Detection of 2,6-Pyridine Dicarboxylic Acid

Qin Wang; Jiangnan Dong; Zhangjian Li; Xinyi Wang; Yabing He; Banglin Chen; Dian Zhao

doi:10.1021/acs.inorgchem.3c02374

Dual-Emitting Mixed-Lanthanide Metal-Organic Framework for Ratiometric and Quantitative Visual Detection of 2,6-Pyridine Dicarboxylic Acid

Inorg Chem. 2023 Sep 4;62(35):14439-14447. doi: 10.1021/acs.inorgchem.3c02374. Epub 2023 Aug 18.

Authors

Qin Wang¹, Jiangnan Dong¹, Zhangjian Li¹, Xinyi Wang¹, Yabing He¹, Banglin Chen^{1

2}, Dian Zhao¹

Affiliations

¹ Key Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua 321004, Zhejiang, China.
² Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China.

PMID: 37595269
DOI: 10.1021/acs.inorgchem.3c02374

Abstract

The detection of the major biomarker of Bacillus anthracis, 2,6-dipicolinic acid (DPA), has attracted great interest in recent years. In this work, mixed-lanthanide metal-organic frameworks (M'LnMOFs), Tb_xEu_1-x-cppa (cppa = 5-(5-carboxypyridin-3-yl)isophthalic acid), with different Tb/Eu ratios, were solvothermally synthesized. The results reveal that ratiometric fluorescent probe [Tb_0.533Eu_0.467-(Hcppa)_1.5(H₂O)(DMF)]·3H₂O is water and acid-base stable and exhibits excellent sensitivity (LOD = 2.286 μM), high selectivity, and fast response (<2 min) for the detection of DPA. Due to the blocked energy transfer from Tb³⁺ to Eu³⁺ and the inner filter effect upon the addition of DPA, the fluorescent probe shows a distinct color change from orange-red to green. Furthermore, the visual detection of DPA was realized by identifying the RGB values of MOF-based agarose hydrogel films via a smartphone, highlighting the practical application of the fluorescent probe for DPA detection under aqueous solution conditions.