In a reducing or denaturing Western blot, proteins are analyzed after they have been denatured and reduced to break their disulfide bonds. This results in a protein sample that is no longer in its native state but allows for the detection of individual subunits or monomers. Usually, the electrophoresis buffer contains SDS to evenly coat the denatured proteins and keep them linearized so that they are separated based on its molecular weight. A native Western blot is used to analyze proteins in their native state without disrupting their structure or interactions. It is typically performed under non-reducing conditions, meaning that the disulfide bonds between cysteine residues are not reduced. Their structure and possibly interactions with other proteins remain intact and influence the migration in during electrophoresis. Reducing Western blots are commonly used to detect a particular protein or subunit of a protein complex. Native Western blots are used to analyze intact proteins or protein-protein interactions.