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Dithiothreitol (DTT) is the common name for a small-molecule redox reagent also known as Cleland's reagent.
D 2384 (OTTO) Dithiothreitol, extra pure, 98%+ Cas 3483-12-3 - used as a reducing or "deprotecting" agent for thiolated DNA. The terminal sulfur atoms of thiolated DNA have a tendency to form dimers in solution, especially in the presence of oxygen.