Dithiothreitol (DTT) is a potent reducing agent commonly used to break down protein disulfide bonds and stabilize enzymes and other proteins. It has a redox potential of -0.33 V at pH 7, making it an unusually strong reducing agent. DTT participates in disulfide exchange reactions and is used at concentrations of 1-10 mM for protein disulfide bond reduction. It is also capable of crossing biological membranes. DTT is used to prevent the formation of mixed-disulfide species and is frequently employed to reduce the disulfide bonds of proteins and prevent the formation of intramolecular and intermolecular disulfide bonds between cysteine residues of proteins. Additionally, DTT can be used as an oxidizing agent, with the principal advantage that effectively no mixed-disulfide species are populated, in contrast to other agents such as glutathione