Ultramicrotome

Brief Description

The Leica UCT is an ultramicrotome which is used to section samples which have been embedded in epoxy plastics or low viscosity plastics (LR Gold, LR White, Spurr, araldite, methacrylate, Lowicryl, etc.) or similar media. Sectioning can be performed with either glass or diamond knives.

Glass knives are used to cut semi-thin sections (0.5-1 mm thick) that are mounted on glass slides and stained with toluidine blue for observation by standard light microscopy. Semi-thin sections are valuable on their own as they reveal fine cytological details not always visible on standard (4-10 mm thick) histological sections. Semi-thin sections are also used to determine which parts of the sample will be thin sectioned with a diamond knife.

Diamond knives are used to cut ultra-thin sections 50 to 100 nm in thickness. These sections are mounted on 3 mm in diameter copper grids (50-150 mesh size), stained with uranium and lead and observed with a transmission electron microscope. Diamond knives can be purchased from electron microscopy supply companies with cutting edges from 1 to 6 mm.