Stains Compatible with Dipping Radioautography

Paraffin sections of 13 different kinds of mouse tissues, containing tritiated thymidine, were used to test stains applied either before or after application of the nuclear emulsion by dipping. Criteria used to determine compatibility were good histological definition with moderate gelatin coloration, sharp contrast to silver granules and no artifact or bleaching. Stains which worked best when applied prior to dipping included Feulgen-fast green, chronium hematoxylin-phloxine, and aldehyde fuchsin-PAS. Stains which worked best when performed after photographic development included celestin blue-Mayer's haemalum, metanil yellow-iron hematoxylin, lithium carmine-picric acid, Weigert acid-iron hematoxylin, alum cochineal, methyl green-pyronin, indigo carmine-picric acid, methylene blue-azure A, toluidine blue, Nissl and Cason. “Combination” stains which worked well when tissues were partially stained before dipping and completed after development included trichrome-PAS, luxol fast blue-PAS, hematoxylin-eosin, and aniline blue-carbol fuchsin.