Please help me with bradford assays - (Jun/04/2006 )
I am doing a bradford assay in hela cells for the first time, using the biorad kit with bsa as a standard. What is the average amount of protein content in hela cells? What concentrations would you recommend for the bsa standard and how do I determine the protein content of my samples? Can I simply extrapolate from the graphs of absorbance?
I've no idea how much protein is in a 'standard' HeLa cell, but I use 2, 5, 10 and 20 µg BSA for making my standard curve (you can add a 1 µg or a 50 µg if you want).
Then you measure your extract (or a dilution of) and simply extrapolate from the standard. It should be that simple. You'll probably find your standard curve is not linear and in that case I use a shallow quadratic a best-fit.
Protein in HeLa
Hope the page could help!
Um protein concentrations depend on the amount of starting material and amount of diluent. In theory, you could make it any concentration you wanted.
When using a 10 cm dish that is grown to confluence, lysed carefully in 600ul lysis buffer, sonicated, and spun for 10 minutes at 8000xg, the resulting 'soluble' fraction is around 1 mg/ml (600-800 ug).
hi! i'm new here! 
I've been searching the net for a complete protocol on how to do the Bradfords assay using the commercial Bradfords reagent from Sigma Aldrich (The prodct sheet that came iwth the reagent seems to have been misplaced 
). Anyway came across this site, and just wondered if any one could help me in this regard, or perhaps guide me to another thread where this question has already been answered, or possible website.
Thanks in advance 
I've been searching the net for a complete protocol on how to do the Bradfords assay using the commercial Bradfords reagent from Sigma Aldrich (The prodct sheet that came iwth the reagent seems to have been misplaced ). Anyway came across this site, and just wondered if any one could help me in this regard, or perhaps guide me to another thread where this question has already been answered, or possible website.Thanks in advance
Protocol from Sigma