Wang Bing, Xia Jinfeng, Zhou Guohong, Li Xin, Dai Mengting, Jiang Danyu, Li Qiang
School of Chemistry and Molecular Engineering, East China Normal University Shanghai 200062 P. R. China
Shanghai Institute of Ceramics, Chinese Academy of Sciences Shanghai 200050 P. R. China.
RSC Adv. 2020 Oct 12;10(61):37500-37506. doi: 10.1039/c9ra09695g. eCollection 2020 Oct 7.
A new fluorescent probe based on terbium(iii)-doped nanosheets was designed for detecting low-levels of dipicolinic acid (DPA), a biomarker of bacterial spores. The ability to detect ultra-low concentrations of DPA is therefore of great significance. First, Tb(iii)-doped ytterbium hydroxide nanosheets were obtained by mechanical exfoliation from layered rare-earth hydroxide (LRH) materials. The morphology of the as-synthesized nanosheets was studied by transmission electron microscopy and atomic force microscopy. The Tb(iii)-doped nanosheets are demonstrated to be highly sensitive to DPA, which remarkably enhances Tb(iii) luminescence intensities at a wavelength of 544 nm. Furthermore, Tb(iii) emission increases linearly with DPA concentration. Selectivity studies were conducted by adding different competing aromatic ligands to the sensing solution; however, their fluorescence responses were observed to be negligibly small in comparison with that of DPA. Our findings provide a basis for the application of Tb(iii)-doped nanosheets for accurate, sensitive, and selective monitoring of DPA as a biomarker of anthrax.
一种基于掺铽（III）纳米片的新型荧光探针被设计用于检测低水平的吡啶二羧酸（DPA），它是细菌孢子的生物标志物。因此，检测超低浓度DPA的能力具有重要意义。首先，通过从层状稀土氢氧化物（LRH）材料进行机械剥离获得了掺铽（III）的氢氧化镱纳米片。通过透射电子显微镜和原子力显微镜研究了合成纳米片的形貌。结果表明，掺铽（III）纳米片对DPA高度敏感，在544nm波长下能显著增强铽（III）的发光强度。此外，铽（III）的发射强度随DPA浓度呈线性增加。通过向传感溶液中添加不同的竞争性芳香配体进行选择性研究；然而，与DPA相比，观察到它们的荧光响应可以忽略不计。我们的研究结果为应用掺铽（III）纳米片准确、灵敏和选择性地监测作为炭疽生物标志物的DPA提供了依据。
