A SDS-PAGE minigel problem

Beatriz Gonzalez-Yanes beatriz at pine.circa.ufl.edu
Mon Feb 3 20:31:02 EST 1992

In article <832.29883ef2 at nphi.fi>, tronni at nphi.fi writes...

(edited for brevity)
>Sometimes a yellow strip appears in the blue front
>when a minigel is run (30 mA per gel). The samples 
>in lanes affected by the yellow strip stop migrating 
>immediately. We have not found out any clear reason 
>for this phenomenon. Buffers are new, as are the 
>other reagents we use. As a sample buffer I use 2 x Laemmli
>sample buffer including 10 % beta-mercaptoethanol.
>Does anybody have any troubleshooting suggestions or similar
I've had the same thing happened to me when my samples were acidic (as 
after TCA precipitation, for example). When I took some of the sample 
buffer and added some acid to it I found that it turned yellow.  I
thought then that probably the color of the coomassie 
brilliant blue is yellow at low pH. However, I found that my samples 
still migrated OK. (But it probably was because I was running regular 
size gels and there was enough buffering capacity to allow my samples 
to run fine).

beatriz at ufpine            beatriz at pine.circa.ufl.edu
Cuando suena el reloj despertador por la man~ana, recuerdo que "al que 
madruga Dios lo ayuda", pero como "nunca es tarde si la dicha es buena"
y "no por mucho madrugar amanece mas temprano", sigo durmiendo.

More information about the Methods mailing list