A New Conductive Substrate for Preparing Cells in Suspension for Scanning Electron Microscopy

Improvement in conductibility of substrates was attempted to overcome a technical problem of charging artifacts caused by limited cell surface attachment to the substrates, when cells prefixed in suspension are observed under SEM. Gelatine-covered slips were impregnated with osmium vapor and coated with polylysine. Using the newly-designed slips, we have succeeded in the elimination of the charging artifacts, such as irregular bright and dark lines parallel to the scan direction or abnormal contrast by a higher magnification. Subsequently, a mesh containing 42 compartments in 25 mm2 was prepared by drawing sharp lines on the above conductive substrates. With a combined use of SEM with light microscopy, this particular mesh has solved another problem of differentiating individual cells in mixed cell populations.