SYPRO Ruby is a sensitive ruthenium-based fluorescent dye that interacts non-covalently with proteins. It is widely used for the detection of proteins separated by acrylamide gel electrophoresis (1-D or 2-D). SYPRO Ruby has two excitation peaks at 280 and 450 nm and emission maxima near 610 nm. Staining with SYPRO Ruby involves only three steps: fixation, staining, and de-staining.

• Step 1- The gel is first fixed in 50% (v/v) methanol and10% (v/v) acetic acid, left for at least 30 minutes or overnight.
• Step 2- The gel is stained with SYPRO Ruby stain.
• Step 3- The stained gel is briefly de-stained with 10% (v/v) methanol and 7% (v/v) acetic acid.
• Step 4- Orange-red bands can be seen when the gel is visualized under UV light or with a blue light source.