[Use of the plasma coagulation method for ultrastructural analysis of biological specimens].

Biological particulate specimens, including Saccharomyces cerevisiae yeast, bovine spermatozoa and human blood cells (normal erythrocytes and leukemic cells) were processed for scanning and transmission electron microscopy using the coagulated plasma technique. The specimens were suspended in frozen and thawed plasma; later, coagulation was induced by adding CaCl2. The clot was cut into small pieces and processed as tissue fragments. The technique is an useful tool when processing biological particulate specimens for electron microscopy.