Procedure for the embedment and ultrastructural visualization of cells cultured on plastic microtest plates

The polystyrene Microtest plate has served as an excellent means of quantitation in the interaction of immunological, chemotherapeutic and radiobiological treatments with cultured cells. In order to assess the accompanying ultrastructural changes it was necessary to develop a technique which allowed cells grown in the wells of the plates to be embedded for electron microscopy. Conventional epoxy resin embedding techniques require the use of propylene oxide as a clearing agent. Unfortunately propylene oxide is a solvent of the polystyrene plates. By the substitution of absolute ethanol for propylene oxide, toluidine blue staining during the procedure and other preparative techniques it was feasible to prepare reacted cells grown in Microtest plates for electron microscopy.