A Hierarchical Nanostructure‐Based Surface‐Enhanced Raman Scattering Sensor for Preconcentration and Detection of Antibiotic Pollutants

A surface‐enhanced Raman scattering (SERS) sensor that integrates a plasmonic nanostructure with an electrostatic preconcentration unit has been developed. The silver nanoparticles (Ag‐NPs) grafted Ge nanowires (Ge‐NWs) are grown onto the surface of a commercial copper grid (Cu‐grid), which is usually used for transmission electron microscopy sample support. This leads to the formation of a hierarchical Ag‐NPs@Ge‐NWs@Cu‐grid substrate, which plays dual roles, i.e., preconcentration of analytes and amplification of SERS signal. This SERS detection platform based on the Ag‐NPs@Ge‐NWs@Cu‐grid substrate is able to selectively detect polar analytes such as antibiotic pollutants. This SERS sensor has achieved a limit of detection of 2.4 × 10⁻⁹m for 6‐aminopenicillanic acid and 0.9 × 10⁻⁹m for penicillin G, respectively. This work has demonstrated a promising SERS detection platform for monitoring polar SERS‐active pollutants in the aquatic environment.