The Microtome Is a Tool Used To Slice Materials Very Thinly

 

Microtome 

A Microtome (from the Greek mikros, meaning "small," and temnein, meaning "to cut") is a cutting tool used to create extremely thin slices of material known as sections. Microtomes are used in microscopy, allowing for the preparation of samples for observation under transmitted light or electron radiation. Microtomes use steel, glass, or diamond blades depending on the specimen being sliced and the desired thickness of the sections being cut. Steel blades are used to cut histological sections of animal or plant tissues for light microscopy. Glass knives are used to cut sections for light microscopy as well as very thin sections for electron microscopy. Industrial grade diamond knives are used to slice hard materials such as bone, teeth and tough plant matter for both light microscopy and for electron microscopy. Gem-quality diamond knives are also used for slicing thin sections for electron microscopy.

Microtomy is an alternative to electropolishing and ion milling for the preparation of thin sections for materials such as bones, minerals, and teeth. With section thicknesses ranging from 50 nm to 100 m, Microtomes sections can be made thin enough to section a human hair across its width. Sections of plants and animals were manually prepared using razor blades in the early days of light microscope development. It was discovered that in order to observe the structure of the specimen under observation, clean reproducible cuts on the order of 100 m were required, through which light could be transmitted. This enabled the use of light microscopes in transmission mode to examine samples.

The origins of the microtome are obscured because the first microtomes were simply cutting apparatuses, and the development phase of early devices is widely undocumented. The development of very thin and consistently thin samples by microtomy, combined with the selective staining of important cell components or molecules, enabled the visualisation of microscope details at the end of the 1800s. The majority of microtomes today are knife-block designs with a replaceable knife, a specimen holder, and an advancement mechanism. Most devices begin cutting the sample by moving the sample over the knife, where the advancement mechanism automatically moves forward to make the next cut for a selected thickness. The section thickness is controlled by an adjustment mechanism, allowing for precise control.