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• Microtome

  A device used to cut extremely thin slices of material, known as sections. Important in science.
• Microtomes


  • Used in microscopy, allowing for the preparation of samples for observation under transmitted light or electron radiation
  • Use steel, glass, or diamond blades depending upon the specimen being sliced and the desired thickness of the sections being cut

  
• Blades used in microtomes


  • Steel blades for preparing sections of animal or plant tissues for light microscopy histology
  • Glass knives for slicing sections for light microscopy and very thin sections for electron microscopy
  • Diamond knives for slicing hard materials such as bone, teeth and plant matter for both light microscopy and electron microscopy
• Microtomy

  The process of preparing thin sections for materials such as bones, minerals and teeth. Microtome sections can be made thin enough to section a human hair across its breadth, with section thickness between 50 nm and 100 μm.
• The earliest form of microtomy was the freehand sectioning of fresh or fixed material using a sharp razor.
• Types of microtomes based on mechanism

  • Rocking
  • Rotary Rocking
  • Sledge microtome
  • Rotary microtome
  • Cryomicrotome
  • Ultramicrotome
  • Vibrating microtome
  • Saw microtome
  • Laser microtome
• Sledge microtome

  • Typical applications are the preparation of large samples, such as those embedded in paraffin for biological preparations. Typical cut thickness achievable is between 1 and 60 μm.
• Rotary microtome

  • Typical cut thickness is between 1 and 60 μm. For hard materials, such as a sample embedded in a synthetic resin, this design can allow good "semi-thin" sections with a thickness of as low as 0.5 μm.
• Cryomicrotome

  • For the cutting of frozen samples, many rotary microtomes can be adapted to cut in a liquid-nitrogen chamber. The reduced temperature allows the hardness of the sample to be increased, which allows the preparation of semi-thin samples. The sample temperature and the knife temperature must be controlled to optimise the resultant sample thickness.
• Ultramicrotome

  • Allows the preparation of extremely thin sections, typically between 40 and 100 nm for transmission electron microscopy. Diamond knives (preferably) and glass knives are used, and the sections are floated on top of a liquid as they are cut and carefully picked up onto grids suitable for TEM specimen viewing.
• Vibrating microtome

  • Operates by cutting using a vibrating blade, allowing the resultant cut to be made with less pressure than would be required for a stationary blade. Usually used for difficult biological samples. Cut thickness is usually around 30–500 μm for live tissue and 10–500 μm for fixed tissue.
• Saw microtome


  • Especially for hard materials such as teeth or bones. Has a recessed rotating saw, which slices through the sample. Minimal cut thickness is approximately 30 μm and can be made for comparatively large samples.

  
• Laser microtome

  • Contact free slicing, prior preparation of sample not required, can be used for very hard materials such as bones or teeth as well as some ceramics, thickness range 10-100 μm.