Résumé : A method of autoradiography that allows discrimination between 35S- and 75Se-labeled material on polyacrylamide gels is described. It involves the incorporation of l-[35S]methionine and l-[75Se]selenomethionine into proteins. The autoradiographic exposure times are decreased at least sixfold with regard to the previously described techniques using 3H- and 14C-labeled proteins. © 1982.