Highly Sensitive Fluorescence Determination of the Anthrax Biomarker Using Tb ³⁺ ‐doped Heterometallic Organic Framework

Anthrax is an acute infectious disease with potential high pathogenicity caused by Bacillus anthracis , which poses a serious threat to human life. Therefore, rapid and efficient detection of the biomarker of B. anthracis , dipicolinic acid (H 2 DPA), is crucial for safeguarding human health. In this study, heterometallic organic framework ZnNa 2 (DPA) 2 (H 2 DPA = dipicolinic acid, also as ligand) was designed and synthesized. In order to enhance fluorescence performance, series of Tb 3+ ‐doped ZnNa 2 (DPA) 2 ( Tb‐1 , Tb‐3 , Tb‐5 , and Tb‐7 ) were prepared. A series of fluorescence detection results demonstrates that Tb‐7 exhibited the best fluorescence quenching effect on H 2 DPA with a quenching constant ( K sv ) of 1.67 × 10 5 M −1 and a limit of detection (LOD) as low as 4.34 μM. The quenching mechanism of Tb‐7 as a fluorescent sensing material was also investigated.