> Hi all,
>
> Is coomassie blue R-250 the choice stain for protein spot quantitation? I ha
ve
> tried sypro orange, however, I can't seem to get its sensitivity any better t
ha
> n coomassie blue (i.e. around 32 ng per band). Has silver staining been used
fo
> r protein spot quantitation? I like the sensitivity of silver staining, howev
er
> , I would be concerned about background staining and how selective the stain i
s
> for different proteins.
>
> Michael Johns
> Lacombe Research Centre
> Lacombe, Alberta
> T4L 1W1
> Canada
>
> Tel: 403-782-8100 ext 268
> Fax: 403-782-6120
Dear Michael,
In my opinion, Coomassie Blue is the best choice for spot quantitation. Try also
Colloidal Blue, although I have not tried it myself for quantitation. It is
approximately 5-10 fold more sensitive than Coomassie. Sypro Orange should be a
nice and sensitive stain, however I have never got it to work in the sensitivity
range that the manufacterer claims to obtain. Has anybody a better experience wi
th
it? Finally, silver stain is not very quantitative for proteins, as you have
guessed, except if you are looking at a protein for which you have a calibration
curve.
Hope that it helps
Axel
--------------------------------------------------------------------------------
Axel Ducret, Ph.D.
Senior Research Biologist
Merck-Frosst Canada Inc.
Dept. Biochemistry and Molecular Biology
P.O. Box 1005
Pointe-Claire-Dorval PQ H9R 4P8
Canada
tel. + (514) 428-3428
fax + (514) 428-4900