Glacial Acetic and Picric Acids as a Fixation for Gel Precipitation

Abstract

DIFFICULTIES are often encountered in reading off immunological reactions on gel plates (cf. immuno-electrophoresis). The gel method, however, has many indisputable advantages over tube precipitation even if the latter is considered more sensitive quantitatively. The former has often been utilized for qualitative studies of the various components involved in immunological reactions. In this connexion it is often important to know whether or not the plate contains a precipitate which is not visible either macroscopically or microscopically (cf. interference microscopy). Various fixatives have been employed in order to detect or accentuate an immunological reaction before proceeding to qualitative studies. Acetic acid and alcohol in various concentrations have been most commonly used for this purpose.