Proposal for improved techniques in electron microscopy

Abstract

A light-insensitive polymer film exhibiting high sensitivity to electron radiation is proposed. An electron-sensitive organic ring of particular isomeric form is incorporated into a polymer matrix, thereby prohibiting its migration or removal by solvents. Exposure to electron radiation with energy as low as 3 ev causes a subtle but permanent change of isomeric state enabling the transformed ring to bind heavy metals. After treatment with a developing reagent, exposure to radiation is indicated throughout the film by permanently bound heavy metal with unexposed areas remaining free of metal. Theoretical considerations of the mechanisms proposed for the expected sensitivity and selective binding of heavy metals are reviewed. Suggested uses for the new film are as a substitute for photographic emulsion in electron microscopy and as a replacement for nuclear emulsion in autoradiography. © 1971.