An Automated System for Cryo-Electron Microscopy Sample Preparation

摘要

Cryo-electron microscopy (CryoEM) is a procedure that has become popular for imaging radiation intolerant structures under electron microscopes. CryoEM involves maintaining the sample at cryogenic temperatures throughout the imaging process This has the effect of minimizing damage caused by the electron beam, and results in higher quality images than can be obtained through more traditional imaging methods. The preparation of samples for cryo-electron microscopy studies is currently a labor and time intensive process. Samples must be applied to an imaging substrate under tightly controlled environmental conditions, formed into a thin film, vitrified with liquid ethane, and placed into temporary storage under cryogenic conditions. The grid preparation process is very sensitive to procedural factors, thus the successful creation of viable samples depends on tightly controlling the conditions under which grids are prepared. Several devices which automate portions of the specimen preparation process are currently in use; however, these systems heavily rely on a human operator to function properly. This thesis describes a system that is capable of fully automating the sample preparation process. The resulting system minimizes the need for human input during specimen preparation, improves process control, and provides similar levels of environmental control. Testing shows that the resulting system is capable of preparing samples without human interaction.