In article <60j82o$i6s$1 at news.fas.harvard.edu>, wong5 at login6.fas.harvard.edu (Donny Wong) wrote:
#Hi everyone,
#
#Does anyone know the true detection limits of silver staining? The
#red-book describes 3 methods of silver staining: a long ammoniacal
#protocol, a shorter non-ammoniacal method, and a rapid 1 hour method. The
#book claims that the first method can detect 2-5 ng of protein, though i
#am a little skeptical. I have only tried the rapid method, and am lucky
#to be able to detect 40-50 ng of protein after over-developing. So if
#anyone has tried either of the lengthier methods, I would appreciate your
#comments on how much you can detect. However, I understand that this
#method is somewhat protein-dependent, and certain proteins just never
#stain well.
Well, I have found that Coomasie G250, when used properly, is capable of
detecting at least 20 ng (some claim 10 ng), while silver that I use is
definitely about 10-fols more sensitive (I don't care what red cookbook says).
I use home-made version of Bio-Rad's "Siver stain plus" protocol (if I remeber
correctly the name; they give ref. that I used).
I'd be very surprised if anyone resorted to silver to detect 50 ng of protein
on standard mini gel.
- Dima
