A synergistic platform for chiral SERS sandwich sensing and photothermal sterilization targeting bacteria

To address the need for rapid detection and simultaneous inactivation of pathogenic bacteria, this work presents an integrated "detection-and-treatment" sensing platform. At the core of this platform is a sandwich-like structure composed of magnetic capture probes, target bacteria, and chiral SERS tags. The capture probes not only efficiently enrich bacteria from complex matrices but also, due to their inherent photothermal properties, can efficiently and rapidly inactivate bacteria and remove biofilms upon excitation by a near-infrared laser, thereby achieving true functional integration of detection and treatment. Meanwhile, D-type SERS tags act as SERS signal amplifiers and enhance binding to bacteria through chiral-selective interactions, opening up new possibilities for expanding SERS applications in chiral recognition and enantiomer discrimination. Experiments demonstrated that the platform achieved limits of detection (LOD) as low as 9 CFU/mL for Staphylococcus aureus and 12 CFU/mL for Escherichia coli, with antibacterial efficiency exceeding 99 % for both bacteria within 10 min. This work not only provides an integrated strategy for rapid pathogen diagnosis and timely intervention, but also opens new avenues for exploring chiral nanomaterials in biosensing and antimicrobial applications.