The use of freeze‐substitution in the preparation of plant tissue for ion localization studies

SUMMARY A method, utilizing freeze substitution, is described for the preparation of plant tissue for analytical electron microscopy. The fine structure of the cytoplasm was adequately preserved after freezing leaf tissue in 2‐methylbutane at −170°C. Furthermore, following substitution in ether, losses of sodium and potassium from the tissue were less than 4% of the original ion content and the loss of chloride was less than 1%. The merits of the procedure as a means of tissue preparation for ion localization studies are discussed.