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Question: What purpose does bromophenol blue serve in my protein isolation? - protein isolation (Feb/06/2008 )

I am beginning a new project and have received a protein isolation protocol from a different lab. I would like to use the Lowry method to quantify the protein, but I am concerned that the bromophenol blue in this protocol might interfere with the absorbance. My questions are:
1) Will the bromophenol blue interfere if using the Lowry method (I think I will purchase Biorad's DC Assay, based on the lowry method)?
2) What is the function of bromophenol blue in protein isolation?
This is the 2x protein isolation buffer recipe:
i. 6mL 1M Tris (pH=8)
ii. 1.0 g DTT
iii. 10mL 2% SDS
iv. 15g Sucrose
v. 0.06g E-Aminocaproic Acid
vi. 0.018g Benzamidine
vii. 0.010g Bromophenol Blue

Thanks!

-Kalisz Lab-

It looks like SDS-PAGE sample (lysis) buffer.

-K.B.-

as k.b. said, it is sds-page sample buffer. the bromphenol blue will interfere with the protein determination. but so will sds and dtt and, to a lesser extent, tris (although you may be able to blank for these).

what is it that you want to do with the protein you isolate with this solution?

-mdfenko-

The bromophenol blue is a dye which migrates with the electrophoretic front due to its high ionic nature and small Mr.

-paraboxa-