a technique for preparing specimens for electron microscopy. The unfixed tissue is frozen and then split with a knife and a layer of ice is sublimed from the exposed surface. The resultant image is thus not distorted by chemical fixatives.
A technique for ?xating specimens of tissue, involving a minimum of chemical and physical alteration. The histological specimen is immersed in a chemical, isopentane, which has been cooled in liquid air to a temperature just below 200 °C. This preserves the tissue instantly without large ice crystals forming – these would result in structural damage. The specimen is then dehydrated in a vacuum for three days, after which it can be examined using a MICROSCOPE.... freeze drying
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