A plasmonic Au-Ag janus nanoprobe for monitoring endogenous hydrogen sulfide generation in living cells.

Hydrogen sulfide (HS) is an essential intracellular gasotransmitter undertaking numerous signaling roles and physiological effects. Herein, an ingenious anisotropic gold (Au)-silver (Ag) Janus plasmonic nanoprobe was constructed based on the dark-field light scattering imaging for the detection of exogenous and endogenous HS. In the presence of sulfide, the Ag islands as the sensing agent were susceptible to oxidation to AgS, which induced changes in the longitudinal localized surface plasmon resonance (LSPR) properties of Au-Ag Janus nanoparticles (JNPs), resulting in remarkable and distinctive scattering color changes as well as spectral shifts. The JNPs exhibited satisfying anti-interference capability and a good linear relationship with a low detection limit of 0.11 nM. Additionally, this distinct nanoprobe was successfully applied to monitor endogenous HS as well as map local variations of HS in real-time with its unique intuition and sensitivity in intracellular imaging applications. This work provided a promising application in the plasmonic detection of intracellular HS and paved insight into the HS-related biological process.