Question

Electron Microscopy: Can TEM and SEM be performed in live mice? If so, are there any apparatus changes necessary?

Answer 1

NO. I dont think that we are able to image the brain of a live mouse using an electron microscope. The samples must undergo complex preparation steps to help them withstand the environment inside the microscope. The preparation process kills the tissue and can also cause changes in the sample’s appearance.There are two reasons why living things can’t survive in an electron microscope:

• The power of the electron beam that’s directed at the sample.
• The vacuum inside the microscope.

The electron beam inside a transmission electron microscope (TEM) causes problems for biological samples because of its high energy. It needs to have enough energy to pass right through the sample and out the other side. The temperature can get up to 150°C where the beam hits the sample. This temperature is far too high for living cells to survive. Scanning electron microscopes (SEMs) use a lower-energy electron beam, but it can still be damaging to the sample.

To be visualised by an electron microscope, biological samples need to be:

• fixed (stabilised) so the electron beam doesn’t destroy them
• dried thoroughly so the vacuum doesn’t affect them.