T 1498 (OTTO) N,N,N′,N′-Tetramethylethylenediamine, for electrophoresis & molecular biology, 99%+ Cas 110-18-9 - used to catalyze the formation of free radicals from ammonium persulfate or riboflavin. The free radicals will cause acrylamide and bis-acrylamide to polymerize to form a gel matrix which can be used for sieving macromolecules.