QDs-Based SERS Technology: Breakthroughs and Prospects From Biosensing to Food Safety

Quantum dots (QDs) have emerged as a promising substrate in surface-enhanced Raman scattering (SERS), due to their quantum confinement effects and tunable optical properties. QDs provide a new solution to the limitations faced by SERS technology, such as poor stability, high cost, and biological toxicity, and demonstrate promising application prospects. This review summarizes recent progress in QDs-based SERS, including synthesis, enhancement mechanisms, and applications. In terms of synthesis strategies, various approaches such as chemical, physical, and biological ones are commonly employed to prepare quantum dots, in order to control their size, morphology, and surface functionalization. In terms of the enhancement mechanism, QDs-based SERS substrate typically combines the advantages of electromagnetic field enhancement and chemical enhancement. For instance, by taking advantage of the quantum size effect and oxygen vacancy engineering to dynamically adjust the local surface plasmon resonance, highly efficient electromagnetic hotspots can be generated in QD semiconductors or in the composite structures of noble metals/QDs. Meanwhile, the quantized energy levels enhance selectivity through resonant charge transfer. Importantly, QDs-based SERS substrate have been applied in wide fields including label-free biosensing of cancer cells, virus identification, multimodal tumor diagnosis, and food safety detection, etc. Despite these advancements, QDs-based SERS substrates still face challenges in terms of anti-interference ability, scalability in manufacturing, and long-term stability. And we propose that enhancing the selectivity and stability of QDs-SERS substrates through methods such as surface modification is an important approach to improving their SERS activity. Additionally, integrating artificial intelligence with composite material design is expected to accelerate its industrialization and sustainable application in the fields of medicine and food safety.