A novel surface cell imprinting-assisted SERS mapping strategy for ultrasensitive bacterial detection

Surface-enhanced Raman spectroscopy (SERS) is widely used for bacterial detection; however, insufficient specificity and quantitative capability are the primary limitations of this technology. In this study, we propose a novel multi-walled carbon nanotube-modified surface cell-imprinting SERS mapping platform that can specifically and quantitatively detect bacteria. This method utilizes a multi-walled carbon nanotube-modified surface cell-imprinting film as a substrate through which Salmonella typhimurium (S. typhimurium) is captured and labeled with SERS tags, generating an enhanced SERS signal indicating target capture. The specificity of this method is demonstrated by comparing its detection of five non-target bacteria. The SERS mapping platform exhibits strong quantification capability for S. typhimurium, with a broad linear range from 10² to 10⁸ CFU/mL and a detection limit of approximately 1.49 CFU/mL. Notably, the SERS mapping platform can effectively detect S. typhimurium in chicken samples for early monitoring of contamination. By fabricating different multiwalled carbon nanotube-modified surface cell-imprinted films, the platform can be adapted to detect additional bacteria or other targets, offering a new approach for practical sample detection.