A New Embedding Technique for Electron Microscopy, Combining a Water-soluble Epoxy Resin (durcupan) with Water-insoluble Araldite

A new water-soluble embedding agent, tr ial p roduc t CIBA X 133/20971 has recently been in t roduced for selected electron microscopic investigations (1). D u r c u p a n subsequently proved to be miscible wi th the water-insoluble epoxy resin Araldi te 2 which is commonly used for tissue embedding (2). In this way, an imal tissues can be embedded in Araldi te wi thout being b rough t into contact wi th e thanol or acetone. By replacing D u r c u p a n wi th Araldi te as final embedding medium, u l t r a th in sections are more readily obta ined t han by employing D u r c u p a n alone. T h e method described below displays some points of resemblance to the one devised by Craig et al. (3) for Epon 812.