Europium functionalized silicon quantum dots nanomaterials for ratiometric fluorescence detection of Bacillus anthrax biomarker.

Bacillus anthracis spore causes anthrax to seriously threaten human health and even cause death. 2,6-Pyridinedicarboxylic acid (DPA) is a unique biomarker because it is a major component of Bacillus anthracis spore. Herein, we design europium functionalized silicon quantum dots as a ratiometric fluorescent nanoprobe to detect DPA with high sensitivity and selectivity. With the addition of DPA, the red emission peaks were observed at 618 nm. The novel probe enables ratiometric and sensitive DPA detection over nanomolar concentrations (as low as 1.02 μM). This work provided an efficient background-free and self-calibrating method for the recognition of DPA.