TEMED (N,N,N’,N’-Tetramethylethylenediamine) is a chemical used as a catalyst in the polymerization of acrylamide and bisacrylamide to form polyacrylamide gels. It accelerates the reaction between acrylamide and the initiator (usually ammonium persulfate) to form the gel matrix. TEMED is commonly used in gel electrophoresis for protein and nucleic acid separation.