AuNPs-decorated and Ni-doped MoS2 for multi-analyte detection in mushroom via SERS and colorimetry

Qualitative and semi-quantitative detection and identification of multiple targets is of great importance in complex sample analysis, while surface-enhanced Raman scattering (SERS) could be an efficient strategy. Here, to efficiently promote the enhancement effect, Ni doping and Au nanoparticles (AuNPs) surface modification were adopted to develop a MoS 2 SERS substrate composed of intercrossed nanoflowers, named AuNPs@Ni-MoS 2 , which exhibits high SERS enhancement towards the Raman reporter (4-mercaptobenzoic acid, 4-MBA) with an enhancement factor (EF) of 10 8 . In complex matrices of different mushrooms, this substrate can also sensitively detect α -amanitin and β -amanitin with a limit of detection (LOD) of 10 −8 M for both, which laid a solid foundation for the accurate discrimination via the following machine learning-based approach. Meanwhile, based on the AuNPs@Ni-MoS 2 substrate, sensitive and specific detection of Hg 2+ was attributed to the formation of an Au-Hg alloy, which could greatly lower the catalytic potential required for the oxidation of the colorless chromogenic agent (3,3’,5,5’-tetramethylbenzidine, TMB) to a yellow oxidized TMB (TMB 2+ ). This study not only provides a reference model for improving charge transfer efficiency in SERS system but also offers technical support for rapid screening multiple analytes in complex samples.