时间：2020-10-31
在单细胞层面进行分子组分分析，可以研究同一个种群内细胞个体之间的差异，尤其是细胞对于外界刺激下的响应过程表现出的异质性，有助于了解引起这些差异性的内在分子机制，对于药物研发、疾病诊断等均具有非常重要的意义。激光光镊拉曼光谱（Raman Tweezers）是一种无损、无标记的单细胞操控和分子组分分析技术。拉曼光镊利用激光的力学效应，将单个细胞或者颗粒物囚禁在光强极值点附近（如图1所示），并激发单个细胞的拉曼散射。通过对拉曼散射光谱提供的分子“指纹”信息可以对细胞中的核酸、蛋白、脂质等生物分子进行定性的分析和定量的测量。图2为单个巨大芽孢杆菌孢子的拉曼光谱。
图1 激光光镊用于单细胞俘获和囚禁
图2. 单个巨大芽孢杆菌孢子的拉曼光谱
拉曼光镊技术不仅可以用于单细胞的识别、分类，还可以用于监测细胞中的生物分子在生物生理过程中的动态响应。此外，拉曼光镊技术还可以与荧光显微、光学成像以及微流控等多种技术集成，实现对单细胞的多模态、高通量测量。图3为拉曼光镊和荧光显微技术相结合用于单芽孢萌发动态过程监测。
图3. 蜡样芽孢杆菌孢子在丙氨酸作用下的动态萌发过程。(a) 单芽孢的相衬显微图像；（b）单芽孢的荧光显微图像（核酸染料 syto 16）；（c）4个不同芽孢萌发过程中CaDPA浓度变化曲线；（d）对应的syto 16荧光强度变化曲线。
除了单细胞拉曼光谱，实验室也利用激光诱导击穿光谱（LIBS）对环境单颗粒物如大气颗粒物、海洋微塑料等进行多元素检测。单颗粒元素组成分析，不仅能够定量评估环境颗粒物对人体健康的影响，而且能够实现对颗粒物的分类、溯源以及排放控制。图4为单颗粒LIBS用于微塑料多元素检测的示意图以及单颗粒的LIBS光谱。
图4. 单颗粒LIBS检测原理以及单颗粒的LIBS光谱
承担课题：
1. 国家重点研发计划课题,口岸食品快检产品和智能监控设备系统化适用性评价研究(2019YFC1605501)，2019.12-2022.12
2. 广西科学院科研发展基金, 水体环境微米级塑料微粒快速鉴别技术的建立及其应用, 2018.08-2021.07
发表的主要论文：
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8. Tao, Z., Peng, L., Zhang, P., Li, Y.Q. and Wang, G., "Probing the Kinetic Anabolism of Poly-Beta-Hydroxybutyrate in Cupriavidus necator H16 Using Single-Cell Raman Spectroscopy," Sensors, 16(8), 1257 (2016).
9. Liang, J., Zhang, P., Setlow, P., and Li, Y.-Q., "High-precision fitting measurements of the kinetics of size changes during germination of individual Bacillus spores," Applied and Environmental Microbiology, 80(15), 4606-4615 (2014).
10. Zhang, P., Liang, J., Yi, X., Setlow, P., and Li, Y.-Q., "Monitoring of Commitment, Blocking and Continuation of Nutrient Germination of Individual Bacillus subtilis Spores," Journal of Bacteriology, 196(13), 2443-2454 (2014).
