Multifunctional magnetic-plasmonic nanoparticles for fast concentration and sensitive detection of bacteria using SERS

► Multifunctional nanoparticles with a gold plasmonic shell and Fe3O4 magnetic core for simultaneous fast concentration and identification of bacteria using surface-enhanced Raman spectroscopy (SERS). ► Multifunctional nanoparticles condensed to a highly compact dot serving as a sensitive SERS-active substrate. ► Quick concentration of bacteria by applying an external point magnetic field to a mixture of bacteria and nanoparticles. ► Efficient differentiation of bacteria via principle component analysis of SERS spectra acquired from the dot area.