Ultrasensitive sulphide detecting by using Au (core)-Ag (shell) triangular nanoprisms.

Hydrogen sulfide (HS), the third endogenous gaseous molecule, plays a crucial role in biological signaling and metabolic processes. It has garnered significant attention from researchers in the field of biochemistry. The highly sensitive detection of HS is essential for elucidating its functions and has long been a key objective in biochemical sensing. In this study, we present an ultrasensitive method for sulfide detection utilizing gold (core)-silver (shell) triangular nanoprisms (Au@Ag TNPs). This strategy is predicated on the preferential formation of AgS at the sharp corners of Au@Ag TNPs, which is manifested as a sensitive spectral shift observed in the nanoprobes. In comparison to the detection limit for sulfide using Au@Ag nanorods, as reported in Nat. Commun.4, 1708 (2013)10.1038/ncomms2722, this detection limit can be enhanced by three orders of magnitude when employing Au@Ag TNPs. Leveraging the single-particle scattering spectrum of individual Au@Ag TNPs, we have successfully reduced the detection limit for sulfide to 1 fM. This represents the lowest reported value for sulfide detection to date. This study presents a highly effective plasmonic nanoprobe for ultrasensitive sulfide detection, which is poised to play a significant role in biochemistry and environmental sciences.