Three Innovations Expand Possibilities of Electron Microscopy Imaging in Fluid

Tuesday, October 13, 2020

The common belief is that electron microscopy (EM) can only be used on dry samples because of the vacuum inside the microscope’s column. This is no longer the case, as researchers can now visualize fully solvated nanoscale objects in liquids such as water from cryogenic to room temperature conditions. Room temperature in-liquid observations are achieved by squeezing the sample into a nanofluidic chip with a very narrow with a very narrow gap (down to 50nm) between two ultrathin membranes, so that the electron beam can get through the “sandwich” and reach the image detector. There are commercial fluid cell products offered on the market, but these have limited functionality.

The Sciaini Group in the Department of Chemistry found three unique innovations in this field. One of their microchip designs allows fluid flow to capture time images and videos of in-liquid nanoparticles (see figure). Another innovative design involves the application of electrodes. This type can be used for studying electrochemical processes on the nanoscale in real-time, in-situ morphology changes on the surface of lithium-ion battery electrodes. They also created a cryo-electron microscope (cryoEM) holder, which eliminates the sample drift and vibrations introduced by the liquid nitrogen dewar. This last version is highly sought in biochemistry and pharmaceutical research for studying protein structures with atomic resolution. All the three technologies are compatible with major brand name electron microscopes.

The designs of these innovative nanofluidic chips and the cryoEM holder are protected by several patent applications. Further developments are now supported by the NSERC Idea to Innovation (I2I) program. “NSERC I2I provided vital financial support towards market assessments as well as the production of prototypes. It allows us to finalize the fabrication of commercial-grade liquid-cell and cryoEM holders for Hitachi and FEI transmission microscopes, and we are about to start the production of JEOL holders”, said German Sciaini.

The group’s next big thing is to get ready to launch a new startup company. They already engaged with WIN’s Startup Catalyst program in developing a business plan.