SDS-PAGE Running Buffer contamination - (Nov/23/2011 )
Recently, we have noticed our 1x SDS running buffer becoming 'contaminated'.
It becomes thick, more viscous then our 10x stock or gooey/goopy. After running and transfering our gel, ponceau staining of the membrane shows a high background starting at the dye front and continuing to enter the gel throughout the run as though there is some sort of contaminating protein in the buffer. The 10x stock is fine and 1x is made in a clean glass bottle with autoclaved water and make in 2L batches which is not kept for more than a couple weeks at a time. 1x buffer is not reused.
What could possibly grow in SDS? Another lab that also works in the space has seen a similar problem. Does anyone have any idea what this might be?
It might be an unwanted chemical reaction. You can visibly tell if it's a microbial contamination. Viscosity would most likely be chemical carry-over? Since another lab in the same space saw the same problem, maybe it's the water source contamination or cleaning apparatus contamination. Autoclaves can transmit contamination of chemicals etc.
Our lab uses filtered Millipore water (the ones with the tank system).