DIRECT ELECTRON, L.P. — Department of Energy SBIR Phase I: 24a

Description

Electron microscopy (EM) is the primary method to image biological cellular ultrastructure, though it has not been possible to label and distinguish different kinds of molecules in a single image- This serious limitation has recently been overcome with the technique of selective lanthanide ion tagging and electron energy-loss filtered imaging yielding multi-color EM that is analogous to multi-color fluorescence microscopy but at up to 100x the magnification- The technique is laborious, relies on expensive equipment, and is quite inefficient since far less than 1% of incident electrons are used to create the elemental maps-An improved technique for multi-color EM will enable the routine imaging of multiple subcellular components, distinguished by individual colors, at the same time- Development of an entirely new direct electron detection sensor and camera system to enable image-wise collection of the entire scattered transmitted beam for each scan point in the Scanning Transmission Electron Microscope (STEM) will enable efficient multi-color EM- The proposed method will use the elastically scattered electrons, (scattering varies as function of Z4/3) to obtain “Z-contrast” and capture nearly 10 – 30% of the incident electrons to get elemental discrimination in the STEM, providing a much higher throughput and more broadly accessible alternative to Electron Energy Loss Imaging- The system, to be useful over large fields of view, will operate at scan rates 2 orders of magnitude faster than current pixelated systems-