Authors: Xuan Chen | Yuhao Wen | Na Zhou | Xiaolin Cao | Maryam Arabi | Ling Ji | Zhiyang Zhang | Lingxin Chen | Jinhua Li
Source: Chinese Science Bulletin (Chinese Version) (article, 2024-03-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Construction and application of molecular imprinting-based surface-enhanced Raman scattering sensors <p indent="0mm">Surface-enhanced Raman scattering (SERS) is an ultra-sensitive vibrational spectroscopy technique used for the characterization and determination of targeted analytes, leveraging the surface enhancement effect. This effect provides structural information about target molecules by measuring their vibration characteristics, akin to fingerprints, and offers advantages such as strong identification, high resolution, and non-destructiveness to samples. As a powerful optical fingerprint technology, SERS can amplify the scattered signal of the target object on the surface of metal nanostructures by millions of times. Consequently, compared with traditional Raman spectroscopy, SERS provides more accurate and sensitive qualitative and quantitative information, showcasing great development potential in numerous fields and finding utility in various detection platforms such as new nanoprobes and instant diagnosis. However, in analytical applications involving complex samples, SERS is susceptible to interference from matrix impurities, making it difficult to quickly identify target objects and limiting its application scope. Therefore, improving the anti-interference ability and selectivity of SERS has always been an important challenge, with molecular imprinting technology (MIT) offering a potential solution. MIT, a multidisciplinary technology capable of mimicking antigen-antibody interactions and constructing selective recognition sites in molecularly imprinted polymers (MIPs), presents a promising avenue. Molecular imprinting-based SERS (MI-SERS) sensors, utilizing MIPs with predictable structure, recognition specificity, and application universality as the recognition/transduction element, combined with the SERS detection technology characterized by fingerprint recognition, non-destructiveness, high sensitivity, and rapidity, demonstrate significantly improved analytical performances. MI-SERS sensors have become an emerging research hotspot due to their outstanding features of high efficiency, precision, and non-destructiveness, showing broad development prospects in fields such as environmental monitoring, food safety, biomedicine, and beyond by providing effective methods for trace analysis of complex matrices. However, the application of MIPs often encounters challenges such as template leakage and low binding capacity, compounded by limitations of the SERS assay itself, hindering further development. While relevant applications of MIPs combined with SERS have been reported, comprehensive reviews on the development of MI-SERS sensors are relatively scarce. In this context, we comprehensively review recent advances in the construction and application of MI-SERS sensors. Firstly, the review will introduce the fundamental sensing mechanisms of MI-SERS sensors. This will be followed by a structural classification based on various usage scenarios, operating procedures, and detection modes. Secondly, typical examples will be examined, focusing on two key aspects: MIPs preparation and SERS substrate improvement. New imprinting strategies and optimization of substrate preparation conditions will be elaborated upon to enhance sensing performance. Furthermore, the review will highlight the point-of-care testing applications of MI-SERS sensors, particularly in relation to the development of portable devices. Finally, the challenges faced by MI-SERS sensors, including stability, enhancement mechanism, universality, and environmental sustainability, will be addressed. Possible solutions to these challenges will be proposed. It is emphasized that addressing current issues such as cost and eco-friendliness, and achieving large-scale stable production, are crucial steps towards bridging the gap from laboratory to real-world applications of MI-SERS sensors. The review will stress the importance of incorporating platform cost, adaptability, and environmental considerations into the early design strategy of MI-SERS sensors, especially those developed for non-laboratory environments. By integrating MI-SERS sensors with advanced technologies such as artificial intelligence, portable devices, and integrated microfluidics, the review aims to realize accurate, rapid, and interference-resistant <italic>in-situ</italic> detection in complex matrices such as food, environment, medicine, and biological samples. By aligning with practical applications, the review will continuously promote MI-SERS sensing technology to improve detection efficiency, thereby facilitating the efficient construction and widespread adoption of MI-SERS sensors. Psychology Gold and Silver Nanoparticles Synthesis and Applications ; Analytical Chemistry and Sensors ; Plasmonic and Surface Plasmon Research