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double bands on p-p70s6k WB - (Sep/06/2019 )

Ran a WB for p-p70s6k with SC Ab(9208), got a 85kDa bands as expected. but it showed double bands of 70kDa and the 70KdA bands look lower than 70kDa. Any help would be appreciated. Thank you.

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What were your conditions for blotting and antibody detection, and what steps have you tried to eliminate non-specific bands? What does the literature, including the product website say about this antibody?


If you are using this antibody: Note the sizes mentioned...


They may be artifacts caused by aged 2-mercaptoethanol (some have identified them as keratin from dust). You can test this by running a sample without protein, but everything else, including the buffer in which your sample is solubilized.
These artifacts usually show up as bands lower than bsa (around 40-50 kDa).


Thank you for your suggestions.  I found a paper published on hematology. The s6k western also showed two bands.They didn't explain this.