A remarkable Coomassie gel stain for SDS-PAGE gels with features and benefits not available from homemade or commercial Coomassie stain preparations.

Since its introduction in the 1960s, the most common method for visualizing proteins within the gel itself is staining with Coomassie Brilliant Blue Dye. The mechanism of Coomassie dye binding to proteins is not completely understood, however, it depends in part on basic and hydrophobic residues. For this reason, binding varies widely among proteins.

Coomassie staining gels turns the entire gel blue, causing high background and making protein bands difficult to see. The Coomassie stained gel must be destained with a methanol/acetic acid mixture to remove background stain, thus allowing the gel to be reprobed with another dye or stain. However, during this destaining process the organic solvents fix the proteins to the gel, making subsequent analysis techniques nearly impossible to perform.

Pierce has developed a unique Coomassie based gel stain, GelCode Blue Stain Reagent, that does not require an organic solvent for destaining. GelCode Blue Stain Reagent utilizes the colloidal properties of coomassie G-250 dye for protein staining on polyacrylamide gels. This unique reagent stains only protein and allows bands to be viewed directly on the gel during the staining process. After staining, a water equilibration step (Water Wash Enhancement) further enhances staining sensitivity and yields a clear background. Because the destaining step does not fix the protein, GelCode Blue is compatible with mass spectral analysis and N-terminal sequence analysis. The GelCode Blue Stain simply requires a 1 hour incubation with the stain and a 1 hour water wash to see nanogram levels of protein (Figure 1).

No tedious, pungent methanol/acetic acid destaining step required

• Saves preparation time and reagent costs
• Reduces solvent disposal problems and associated costs
• No destaining step necessary – no losses from over destaining

Fast, one-step, one-hour staining

• Ready-to-use stain reagent
• Bands develop before your eyes and can be viewed directly in the staining tray
• No increased background from overnight staining
• Completely flexible fixing and washing protocols can be used
• No gel shrinkage – original gel dimensions maintained
• Stained gel can be dried

More sensitive than standard Coomassie gel stain formulations

• Some protein bands visible to 8 ng
• Wide linear range for densitometric gel analysis¹
• Allows gel staining after Western transfer
• Compatible with MALDI-TOF analysis^2,3,4
• Compatible with sequence analysis⁵

Water Wash Enhancement Step increases staining sensitivity

• Crystal-clear gel background
• Even the weakly stained bands become easily visible

Traditional Coomassie Stain Formulation		Pierce GelCode Blue Stain Reagent
Staining time: 1 hour No bands observed before destaining.		Staining time: 1 hour Bands clearly visible in the staining tray.
After destaining 1 hour in methanol:acidic acid.		After 1 hour of Water Wash Enhancement. Crystal-clear background and excellent sensitivity to 8 ng.

Figure 2. GelCode Blue Staining Protocol.

References:

1. Mateer, S.C., et al. (2002). J. Biol. Chem. 227, 12324-12333.
2. Aulak, K.S., et al. (2001). Proc. Natl. Acad. Sci. USA 98, 12056-12061.
3. Lim, J., et al. (2002). J. Biol. Chem. 277, 20774-20782.
4. Hilton, J.M., et al. (2001). J. Biol. Chem. 276, 16341-16347.
5. Tani, M., et al. (2000). J. Biol. Chem. 275, 3462-3468.

Ordering Information

Certificate of Analysis   Product Instructions   MSDS

Buy Product # Description Pkg. Size Files Price Add 24590 GelCode Blue Stain Reagent Sufficient for staining up to 25 SDS-PAGE mini gels (8 cm x 10 cm). 500 ML $63.00 Add 24592 GelCode Blue Stain Reagent Sufficient for staining up to 175 SDS-PAGE mini gels (8 cm x 10 cm). 3.5 L $241.00 Add 72300 Pump (for 3.5 liter package only) A complementary reagent dispensing pump attachment is available FREE upon request for Product # 24592. Specify Product # 72300 when you place your order. 1 pump $0.00