Practice question

Denaturing buffers for agarose electrophoresis of RNA employ agents that disrupt secondary structures and prevent renaturation during migration. Glyoxal and dimethyl sulfoxide (DMSO) covalently and non-covalently modify guanine residues, preventing base pairing and maintaining linear conformation. Formaldehyde at alkaline pH and formamide perform similar denaturing functions by disrupting hydrogen bonds. EDTA, while not a denaturant, chelates magnesium to inhibit RNases. TEMED, N,N,N',N'-tetramethylethylenediamine, is exclusively a catalyst for polyacrylamide polymerization, accelerating free radical formation from persulfate. It has no role in agarose chemistry or RNA denaturation.