Gold nanoparticle decorated flexible carbon cloth for sensitive detection of 2, 6-pyridine dicarboxylic acid by surface-enhanced Raman scattering

The lethal bacterium of bacillus anthracis has been recognized as a kind of formidable biological warfare agent, and the biomarker of 2, 6-pyridine dicarboxylic acid (DPA) is a crucial component of the protective layer of anthrax spore. The development of an efficient and sensitive detection method for DPA is necessary to prevent the potential biological threats. In this experiment, the porous carbon cloth (CC) and different sizes of gold nanoparticles (AuNPs) are composited together to construct a flexible SERS substrate of AuNPs@Au/CC. The high surface-enhanced Raman scattering (SERS) performance of AuNPs@Au/CC substrate is assessed by the probe molecule of Rhodamine 6 G (R6 G). During the detection of DPA, the SERS substrate of AuNPs@Au/CC exhibits a linear detection range from 10^-7 M to 10^-13 M with a limit of detection (LOD) of 1.58 × 10^-13 M. The flexible CC substrate decorated with different sizes of AuNPs can facilitate the contact of DPA molecules and enhance the Raman signal. It provides potential application for the rapid and sensitive DPA detection for preventing the biological threats.