Development of an Ultra-Stable and Repeatable Stage for Enabling Transmission Electron Microscopes with Improved Biomolecular Structure Characterization Capabilities

Transmission electron microscopes (TEMs) are a cornerstone of directly-resolved information about the structure and dynamics of the atomic world in biological and inorganic materials alike. Cryoelectron microscopy (Cryo-EM) and tomography (Cryo-ET) are techniques that directly support research to “understand, predict, and design biological processes that underpin innovations for bioenergy and bioproduct production,” as stated by the DOE in their recent SBIR solicitation. Furthermore, these techniques are uniquely capable of providing 3D maps of hydrated biomolecules and are therefore critical to our understanding of life processes at the level of molecular structure and physics. As an imaging technique, Cryo-EM is heavily dependent on the autonomous acquisition of large volumes of image data. However, TEM sample motion control stages (goniometers) in modern TEMs are mechanically and thermally unstable. Mechanically, the motion provided by these devices is unrepeatable. Thermally, they are susceptible to temperature gradients, which cause the sample to drift away from the field of view continually. This makes the stage currently one of the most limiting components of the cryo TEM. Our solution is to provide a better stage for Cryo-EM applications that can be retrofitted to a wide variety of TEM columns for widespread access to the best and fastest Cryo-EM workflows. We propose an internal design for a 5-fold improvement in stability by alleviating the adverse effects of temperature and vibration on resolution. The design also features piezo motor technology to reduce mechanical backlash and other errors that plague current designs for a 100-fold improvement in precision, which will dramatically improve automated image acquisition workflows. Our design also lends itself to highly automated multi-sample Cryo-EM workflows for which we will design an integrated, easy-to-use auto sample loading device. As a product, this system will be integrated into a microscope column segment that can be adapted for compatibility with multiple brands and models of TEM. The combination of these features can dramatically lower the barrier to resolving 3D protein complex structures at near-atomic resolutions