One-step synthesis of LYH:Tb and LYH:Eu film probes and their application in Bacillus anthracis recognition.

In this study, two new photoluminescent film probes (LYH:Tb and LYH:Eu) were developed through chemical bath deposition. Benefiting from the antenna effect of DPA, these films can enhance the characteristic fluorescence emission of Tb3+ and Eu3+ through energy transfer, enabling stable fluorescence detection of the anthrax spore biomarker, pyridine dicarboxylic acid (DPA). By adding various aromatic organic compounds for selectivity studies, it was found that their fluorescence responses were much lower than that of DPA, indicating that the LYH:Tb and LYH:Eu film probes exhibited excellent sensitivity and anti-interference properties for DPA detection. The detection limits of the LYH:Tb and LYH:Eu film probes are as low as 86 nM and 14 nM, respectively. Moreover, the film probe is characterized by its simple synthesis, convenient storage, excellent stability, rapid response, and suitability for visual monitoring.