SDS-PAGE Loading Dye 4X is a concentrated dye used for preparing protein samples for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). This dye contains SDS, which imparts a negative charge to proteins, and other components that facilitate sample loading and visualization. The 4X concentration ensures that the dye can be diluted to the working concentration needed for gel electrophoresis, making it suitable for a variety of protein analysis applications. The SDS-PAGE Loading Dye 4X is a concentrated solution containing sodium dodecyl sulfate (SDS), glycerol, bromophenol blue, and other stabilizers. SDS is a detergent that denatures proteins and imparts a negative charge, allowing for their separation based on size during electrophoresis. The glycerol ensures that the samples sink into the wells of the gel, and bromophenol blue provides visual tracking of the sample during electrophoresis.