Acta Chimica Sinica ›› 2023, Vol. 81 ›› Issue (8): 990-1001.DOI: 10.6023/A23040166 Previous Articles     Next Articles

Review

冷冻电子显微镜技术进展及环境研究应用

杨宇洁a, 巩宇锈a, 顾天航a,*(), 张伟贤a,b,*()   

  1. a 同济大学环境科学与工程学院 污染控制与资源化研究国家重点实验室 上海 200092
    b 岭南现代农业科学与技术广东省实验室 广州 510642
  • 投稿日期:2023-04-26 发布日期:2023-09-14
  • 作者简介:

    杨宇洁, 同济大学环境科学与工程学院2021级硕士生, 研究方向为纳米零价铁环境应用.

    巩宇锈, 同济大学环境科学与工程学院2017级博士, 研究方向为纳米零价铁修复重金属污染土壤.

    顾天航, 同济大学环境科学与工程学院2018级博士生, 研究方向为纳米零价铁富集水中稀有元素, 已发表SCI论文10余篇.

    张伟贤, 教授、博士生导师, 国家特聘专家, 2011年起任污染控制与资源化研究国家重点实验室主任. 1984年毕业于同济大学, 1996年获美国约翰•霍普金斯大学(The Johns Hopkins University)环境工程博士学位, 曾任美国里海大学(Lehigh University)教授. 主持过国家自然科学基金海外及港澳学者合作研究基金及多项国家自然科学基金项目. 长期致力于环境中重金属及持久性有机污染物的基础与应用研究, 是环境纳米技术的先驱之一, 纳米零价铁技术的创始研究者. 在纳米零价铁合成、表征、污染物反应机理、应用于地下水修复及废水处理方面发表了系列经典论文.

    庆祝《化学学报》创刊90周年.
  • 基金资助:
    项目受广东省重点领域研发计划(2020B0202080001); 国家自然科学基金(51978488)

Progress and Environmental Research Applications of Cryo-Electron Microscopy

Yujie Yanga, Yuxiu Gonga, Tianhang Gua(), Wei-xian Zhanga,b()   

  1. a State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092
    b Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642
  • Received:2023-04-26 Published:2023-09-14
  • Contact: *E-mail: tianhanggu@tongji.edu.cn; zhangwx@tongji.edu.cn
  • About author:
    Dedicated to the 90th anniversary of Acta Chimica Sinica.
  • Supported by:
    Key-Area Research and Development Program of Guangdong Province(2020B0202080001); National Natural Science Foundation of China(51978488)

Electron microscopy (EM) is one of the most important techniques to characterize the morphology and structure of micro- and nano-particles. However, conventional procedures for sample preparation often alter the structure and morphology of samples with high water contents, causing distortions and misinterpretations for EM characterizations. The invention of Cryo-electron microscopy (Cryo-EM) has largely solved this problem. Via rapidly freezing the hydrated samples at low temperatures, cryogenic techniques instantaneously transform liquid water into amorphous ice to ensure high vacuum and reduce electron radiation damage, allowing researchers to observe hydrated samples in their native state with high resolution. For example, applications of Cryo-EM during the COVID-19 pandemic have demonstrated the amazing ability of Cryo-EM to visualize the detailed structure of SARS-CoV-2 viruses, which provides vital knowledge for rapid and reliable detection and diagnosis of the disease, transmission mitigation, and vaccine development. So far, Cryo-EM technology has been widely used in materials, biology, pharmaceuticals, and other fields of research, successfully broadening and deepening the understanding of the interactions between micro- and nano-particles. This review summarizes the recent development of Cryo-EM from aspects of electronic components, imaging technology, and resolution and introduces the sample preparation methods. Furthermore, the three-dimensional reconstruction method is highlighted to advance the EM method from 2D to 3D. As most environmental samples are highly hydrated, Cryo-EM will likely become an essential tool to investigate microscopic particles in the environmental field. This review gives examples of the applications of Cryo-EM in the formation of aerosol particles in the atmosphere, observing biofilm morphology in the water treatment process, the pore structure of activated sludge flocs, and the potential mechanism of soil microorganisms on heavy metal remediation. Finally, the prospects of Cryo-EM are summarized and discussed. We expect that with software, hardware, and artificial intelligence development, Cryo-EM technology can achieve faster data acquisition and higher resolution and make breakthrough contributions to environmental chemistry research.

Key words: Cryo-electron microscopy (Cryo-EM), rapid freezing, hydrated samples, glassy ice, three-dimensional reconstruction (3D reconstruction), environmental chemistry