The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for COVID19, a new emerging pandemic affecting humans. Here, single viruses were analyze by atomic force microscopy (AFM) operating directly in a level 3 biosafety (BSL3) facility, which appeared as a fast and powerful method to assess infectious virus morphology in its native conformation, or upon inactivation treatments, at the nanoscale level and in 3D. High resolution AFM reveals structurally intact infectious and inactivated SARS-CoV-2 upon low concentration of formaldehyde treatment. This protocol allows the preparation of intact inactivated SARS-CoV-2 particles for safe use of samples out of level 3 laboratory, as revealed by combining AFM and plaque assays, to accelerate researches against the COVID-19 pandemic. Overall, we illustrate how adapted BSL3-atomic force microscopy is a remarkable toolbox for rapid and direct virus identification and characterization.

中文翻译：

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使用高分辨率原子力显微镜直接可视化天然传染性SARS-CoV-2及其灭活形式

严重的急性呼吸综合症冠状病毒2（SARS-CoV-2）导致了COVID19，这是一种正在影响人类的新出现的大流行。在这里，单个病毒是通过直接在3级生物安全（BSL3）设施中运行的原子力显微镜（AFM）进行分析的，这似乎是一种快速有效的方法来评估感染病毒在其天然构象或灭活处理后的形态，纳米级和3D模式。高分辨率原子力显微镜显示低浓度甲醛处理后结构完整的传染性和灭活SARS-CoV-2。该协议允许制备完整的灭活SARS-CoV-2颗粒，以便安全地从3级实验室中使用样品，这是通过结合AFM和噬菌斑测定揭示的，从而可以加速针对COVID-19大流行的研究。总体，