In vitro investigation of biological specimens by electron microscopy.

A microchamber was developed for the examination of biological specimens in nearly natural environments, in an electron microscope, at 70kV accelerating voltage.. The chamber can be supplied continually with the sample and with the reagents, which makes it suitable for the study of biochemical reactions, too. Temperature and vapour pressure in the chamber can be controlled and the thickness of the specimen can be varied. Transmission electron micrographs of biological specimens, such as human blood cells, bull gametes and Bacillus subtilis have been obtained. Mobility of microorganisms, which is regarded as a criterion of the wet state, has been observed.