Research progress of surface-enhanced Raman scattering sensors for the detection of antibiotic residues in food and environment: mechanism, substrate design and challenges

Abstract

Surface-enhanced Raman scattering (SERS) technology shows great potential for on-site detection of antibiotic residues in food and environmental matrices due to its high sensitivity, rapid response, and unique molecular fingerprint recognition capability. This article systematically reviews the latest research progress of SERS antibiotic sensors, focusing on four aspects: enhancement mechanisms, substrate design strategies, practical application challenges, and future directions. First, starting from the basic principles of electromagnetic enhancement and chemical enhancement, the milestone work of single-molecule SERS is introduced, and the guiding role of density functional theory calculations in revealing the relationship between antibiotic adsorption orientation and signal intensity is discussed. Second, the design strategies from metal nanoparticles to composite substrates are summarized, with particular emphasis on the advantages of carbon materials and two-dimensional materials hybridized with metal/metal oxide substrates in synergistic enhancement and anti-interference. Then, the system analyzed the three major core challenges hindering the practical application of SERS sensors: matrix interference from complex samples, difficulty in selective recognition of structurally similar antibiotics, and insufficient reliability and reproducibility of signal quantification. In response to these challenges, this paper summarizes solutions such as surface functionalization, molecular imprinting/aptamer modification, internal standard methods, and uniform substrate preparation. Finally, the future development directions of this field were envisioned, including the integration of SERS with microfluidic chips to achieve automated sample pre-treatment, machine learning-assisted spectral data analysis, and the standardization and cost control for commercial portable sensors. This review aims to provide theoretical guidance for the design of high-performance SERS antibiotic sensors and promote their practical application in food safety and environmental monitoring.