painful gel loading???!!!!!!

[Mark S. Rose]

In article <32FB5C55.43A at mindspring.com>, natldiagnos at mindspring.com wrote:

> Xudong Huang wrote:
> 
> Hello,
> 
> I have a painful problem about agarose gel loading. The DNA samples do
> not stay at the bottom of wells, intead, they float out of wells and
> diffuse into the buffer. The loading buffer I use is 6XBPB, the gel
> running buffer is 1X TBE. It is not because of air bubbles or oil in the
> samples. Could you let me know what is going on? Thank you.
> 
> Xudong Huang
> email:xudong.huang at endo.mas.lu.se
> 
While ethanol in your sample will cause loading problems I think your
problem is with your loading dye.  A loading dye requires more than dye to
make it dense enough to sink to the bottom of a gel well.  Try adding 40 %
sucrose or 30% glycerol to your loading dye.

-- 
Mark Rose
USDA-ARS
Plant Pathology Dept.
NCSU
Raleigh,NC 27695-7616