Reducing effects of particle adsorption to the air–water interface in cryo-EM

• DOI: 10.1038/s41592-018-0139-3
• Publication Date: 2018-09-17T10:01:54Z
• Authors: Alex J. Noble; Hui Wei; Venkata P. Dandey; Zhening Zhang; Yong Zi Tan; Clinton S. Potter; Bridget Carragher
• Keywords: Cryo-Electron Microscopy; Particle (ecology); Single-Particle Analysis

Most protein particles prepared in vitreous ice for single-particle cryo-electron microscopy (cryo-EM) are adsorbed to air-water or substrate-water interfaces, which can cause the particles to adopt preferred orientations. By using a rapid plunge-freezing robot and nanowire grids, we were able to reduce some of the deleterious effects of the air-water interface by decreasing the dwell time of particles in thin liquid films. We demonstrated this by using single-particle cryo-EM and cryo-electron tomography (cryo-ET) to examine hemagglutinin, insulin receptor complex, and apoferritin.