How does this microtome work?

November 13, 2009 3:20 PM

Has anyone here used a porter-blum mt2 microtome? What do the adjustments do?

So there's a microtome that was sitting under a lab bench collecting dust and I decided to see if I could use it for something, but I'm confused by the controls. Specifically, there is a dial on the left side marked "Thickness" that can be set from 0 to 18 but no units are marked. There is also a screw type dial on top of the microtome that also seems to have something to do with section thickness and has measurements in angstroms. What are the units corresponding to the numbers on the left hand dial, and how does adjusting the two dials affect section thickness? Thanks in advance.

posted by 12%juicepulp to Science & Nature (3 answers total)

"Micro" usually implies micrometer scale. Would help to know what this is used to cut - tissue microtomes I have used have cut on a micrometer scale, and without any units listed I'd guess that is what is being used - but the angstrom marking on the other dial makes me wonder. Could be that the main dial is the thickness setting, and the angstrom dial is for calibration, but I am simply guessing here. All I've used is American Optical sledge microtomes.
posted by caution live frogs at 4:42 PM on November 13, 2009

I don't know microtomes, and I sure don't know your microtome, but you might have an"ultramicrotome," which can cut thicknesses measured in hundreds (?) of angstroms for transmission electron microscopy. 100 angstroms is 0.01 µm; their use would allow you to deal with nice, friendly, larger-than-one numbers.
posted by pullayup at 5:27 PM on November 13, 2009

I have no idea about anything here, but a quick Googling brought up a book about electron microscopy, "Electron microscopy: principles and techniques for biologists" with a section on the MT2, which describes it as an ultramicrotome design from 1962 and goes on to discuss how it works, and how to use it. Not sure I can map their description to your description, but you might want to take a look yourself.
posted by effbot at 5:55 PM on November 13, 2009