Metal–organic framework-based SERS probes with enrichment capability for trace detection: applications in biomarkers and pollutants

Surface-enhanced Raman scattering (SERS) has emerged as a powerful tool for trace substances detection due to its exceptional sensitivity, high anti-interference capability, and ease of operation, enabling detection at the single-molecule level. This makes SERS particularly promising for applications such as environmental monitoring, biomedical diagnostics, and food safety. Despite these advantages, SERS faces limitations due to the difficulty of enriching trace substances and the small Raman scattering cross sections of certain molecules. Metal–organic frameworks (MOFs), characterized by their high surface areas and porosity, tunable structures, and diverse functionalities, offer a promising solution to these challenges. By integrating MOFs with SERS technology, we explore how MOF-based SERS probes can enhance the sensitivity, selectivity, and efficiency of trace substance detection through mechanisms such as analyte enrichment, selective molecular capture, and electromagnetic field manipulation. In this paper, a comprehensive review of the structure and synthesis of MOF-SERS composites is presented, with an emphasis on their application in the detection of trace substances. The paper also discusses key challenges in the design and optimization of MOF-based SERS probes, particularly in terms of stability, reproducibility, and integration with existing detection platforms, aiming to broaden their practical applications and improve their detection efficiency.