Laemmli's (SDS-Sample) Buffer is widely used in molecular biology and biochemistry for protein analysis. Its primary application is in SDS-PAGE (Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis), where it prepares protein samples for separation based on molecular weight. The buffer denatures proteins by breaking non-covalent bonds, ensuring they unfold into linear chains. It also provides a negative charge to the proteins, proportional to their size, allowing them to migrate uniformly in an electric field. Additionally, it contains a tracking dye to monitor the progress of electrophoresis and glycerol to help load samples into gel wells. This buffer is essential for accurate protein analysis, immunoblotting, and studying protein composition in various biological samples.