Ponceau-S, Sodium Salt (CAS 6226-79-5)

Ponceau-S, Sodium Salt, with the CAS number 6226-79-5, is a synthetic azo dye primarily used in biochemical research for staining proteins on membranes, a critical step in procedures like Western blotting and other types of protein immunoassays. This dye is highly valued for its rapid staining abilities and its reversible nature, allowing for non-destructive visualization of proteins. Ponceau-S binds electrostatically to protein molecules, specifically to basic amino acid residues, which makes it an effective tool for assessing protein transfer from gels to membranes before more specific immunodetection methods are applied. The reversible staining property of Ponceau-S is particularly useful as it can be easily washed away without leaving permanent marks on the membrane, thus permitting subsequent probing with specific antibodies or other detection methods without background interference. In research settings, the use of Ponceau-S facilitates the quick verification of protein transfer efficiency and provides a preliminary qualitative assessment of protein levels across samples. This helps in optimizing the conditions for further detailed analyses and ensures the reliability of experimental results in protein-based studies. Its ease of use, coupled with the ability to rapidly visualize and then erase its staining, makes Ponceau-S an indispensable tool in molecular biology labs engaged in protein research.