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A Fast and Effective Microfluidic Spraying-Plunging Method for High-Resolution Single-Particle Cryo-EM.

ABSTRACT: We describe a spraying-plunging method for preparing cryoelectron microscopy (cryo-EM) grids with vitreous ice of controllable, highly consistent thickness using a microfluidic device. The new polydimethylsiloxane (PDMS)-based sprayer was tested with apoferritin. We demonstrate that the structure can be solved to high resolution with this method of sample preparation. Besides replacing the conventional pipetting-blotting-plunging method, one of many potential applications of the new sprayer is in time-resolved cryo-EM, as part of a PDMS-based microfluidic reaction channel to study short-lived intermediates on the timescale of 10-1,000 ms.

SUBMITTER: Feng X

PROVIDER: S-EPMC5382802 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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A Fast and Effective Microfluidic Spraying-Plunging Method for High-Resolution Single-Particle Cryo-EM.

Feng Xiangsong X Fu Ziao Z Kaledhonkar Sandip S Jia Yuan Y Shah Binita B Jin Amy A Liu Zheng Z Sun Ming M Chen Bo B Grassucci Robert A RA Ren Yukun Y Jiang Hongyuan H Frank Joachim J Lin Qiao Q

Structure (London, England : 1993) 20170309 4

We describe a spraying-plunging method for preparing cryoelectron microscopy (cryo-EM) grids with vitreous ice of controllable, highly consistent thickness using a microfluidic device. The new polydimethylsiloxane (PDMS)-based sprayer was tested with apoferritin. We demonstrate that the structure can be solved to high resolution with this method of sample preparation. Besides replacing the conventional pipetting-blotting-plunging method, one of many potential applications of the new sprayer is i ...[more]

PMID: 28286002

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