LDS Sample Buffer (Reducing) is a sample prep buffer used for prior to running proteins in gel electrophoresis, often in SDS-PAGE and Western blot workflows. When added to a protein sample, the buffer unfolds proteins, imparts a uniform negative charge, and the reducing formulation breaks disulfide bonds. In addition, the buffer contains glycerol to increase sample density, allowing the sample to sink into wells effectively. Coomassie blue and phenol red function as tracking dyes, coomassie blue offers protein visualization and phenol red functions as a front marker for the gel.