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problem with loading the protein on to SDS-Gel - (Oct/18/2011 )

Hi

I am purifying a protein by SP-sepharose cation exchange column. The buffer i use to elute the protein contains potassium chloride in it. Therefore as soon as i add 4X SDS dye to my sample, it precipitates and on heating it becomes sticky and gelatinous. I need to run the protein on the gel to check where my protein is eluted. I cannot load because its too sticky and it wont run on the gel. Any suggestions?

-deep1985-

1. Can't you use sodium chloride or lithium chloride for elution?
2. You could try buffer exchange with dialysis, ultrafiltration or gel filtration (eg. PD-10 columns).

-K.B.-