Electrophoresis Run - GE SE 250 Mighty Small II Operating Instructions Manual

5 Operation

5.3 Electrophoresis run

5.3 Electrophoresis run
Running the gel
Gels may be run at either constant current or constant voltage. A constant current setting
is traditionally used with a discontinuous buffer system so that the rate of electrophoretic
migration remains unchanged throughout the run. Under these conditions, voltage in-
creases as the run proceeds. A lower current setting is recommended for higher resolu-
tion. Precast gels are run under the same current and voltage conditions as self-cast
gels.
It takes about one hour to run two 7 cm × 0.75 mm Laemmli gels at 40 mA (20 mA per
gel, constant current). Check band progress after 5 minutes, and again after half an
hour, keeping an eye on the position of the tracking dye. The run is complete when the
tracking dye reaches the bottom of the gel. Watch the buffer level in the upper buffer
chamber and, if necessary, replenish it before it falls below the level of the notched plate.
A small volume of buffer may leak past a chipped plate or nicked gasket, or it may wick
out through the gel.
After the run
Step
1
2
40
NOTICE
After initial monitoring, do not leave the unit unattended for more
than 45 min before checking the progress of the bands and the
buffer level.
WARNING
Always disconnect the high voltage leads from the power supply
before removing the lid from the unit.
Action
Once the tracking dye reaches the bottom of the gel, turn off the power
supply, disconnect the leads, and remove the safety lid as described in
assemble a fully assembled unit, on page 31
If coolant is circulating, stop the flow and disconnect the fittings or tubing.
SE 250/260 Mighty Small II Operating Instructions 29281629 AA
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