指纹光谱病原菌快速检测研究进展与趋势

病原菌检测对于保障饮用水和食品安全，应对突发公共卫生事件至关重要。现行检测标准或方法存在操作耗时费力，成本高等缺陷，难以满足现代社会高时效性要求，因此开发操作简单、低成本的病原菌快检技术迫在眉睫。近年来，随着激光技术和光电探测技术的高速发展，能够快速获取微生物指纹信息的激光光谱引起了研究者的广泛关注，其中表面增强拉曼光谱（SERS）和激光诱导击穿光谱（LIBS）由于具有快速、原位无损或微损检测等优点，在病原菌快速检测领域广受关注。SERS作为一种分子振动光谱技术，是在常规拉曼（Raman）光谱中引入具有光学信号放大作用的贵金属纳米结构，实现Raman信号数量级的提升同时能够猝灭荧光，因此可以快速获取目标分子的指纹光谱信息。然而受贵金属纳米粒子的材质、形貌、大小等自身属性，以及与待测物距离等多种因素的影响，重现性仍然是SERS在细菌检测中的一大瓶颈。LIBS作为一种新兴的原子发射光谱技术，具有多元素实时检测的能力，可以快速获取样品包括微量和痕量元素在内的所有元素信息。LIBS进行细菌分类和鉴别时，为了降低基底、共存基质的元素干扰，需采集大量纯培养细菌的光谱数据，不仅增加了检测周期，同时带来定性定量难两全的局面。结合SERS和LIBS技术在病原菌快检领域的研究现状，综述了两类方法各自的优势和局限性，并对其在病原菌快速检测领域的发展趋势进行了展望，为开发基于激光光谱的病原菌快检技术提供参考意见。

Research Advances and Trends of Rapid Detection Technologies for Pathogenic Bacteria Based on Fingerprint Spectroscopy

Pathogen detection is essential to ensure the safety of drinking water and food, and handle public health emergencies. However, the current testing standards or methods have the defects of labor-intensive, time-consuming operation and high cost, which makes it difficult to meet the requirements of high timeliness in modern society. Therefore, developing rapid detection technology for pathogenic bacteria with simple operation and low-cost is extremely urgent. In recent years, with the rapid development of laser and photoelectric detection technologies, laser-based spectral technologies, which can quickly obtain fingerprint information of microorganism, have attracted wide attention from researchers. Among them, surface enhanced Raman spectroscopy (SERS) and laser induced breakdown spectroscopy (LIBS) with the advantages of rapid, non-destructive or micro-destructive detection in situ have been widely investigated in rapid detection of pathogens. As a molecular vibrational spectroscopy technique, SERS introduces noble metal nanostructures with optical signal amplification capability into conventional Raman spectroscopy, which can enhance the Raman signal order of magnitude while quenching fluorescence, so that the fingerprint spectrum information of the whole bacterial cells can be quickly obtained. However, due to the material, morphology, and size of noble metal nanoparticles and the distance between nanoparticles and the target, reproducibility is still a major bottleneck for SERS in bacterial detection. As an emerging atomic emission spectroscopy technique, LIBS has the capability of real-time detection of multiple elements, and can quickly obtain all element information of samples including micro and trace elements. When using LIBS to classify and identify bacteria, in order to reduce the elemental interference of the substrate and the coexisting matrix, it is necessary to collect a large number of spectral data of pure cultured bacteria, which not only increases the detection period but also lost the quantitative capability at the same time. In view of the research status of SERS and LIBS technology in the rapid detection of pathogenic bacteria, this review summarized the advantages and limitations of the two methods and forecasted their research trends in the fields of bacterial detection, thus providing references for the development of rapid detection techniques for pathogens based on laser spectroscopy.