Semidry Electroblotter
3-1
Thermo Scientific
Section 3
Using the System
1. Place and loosely tighten down the lid with the supplied black knobs.
The weight of the lid is usually enough, and the screws are not
required.
Note:
Do Not Use the screws for gels thicker than 1.5mm, or
when using more than 6 filter pads (total). If the screws are used, tip
the unit on an angle, to drain off any excess buffer that may have
squeezed out. This will safely remain in the moat around the electrode
plate.
2. Attach the power leads (red to red, black to black) to an appropriate
power supply. The red lead has a shroud, that will stop it from
attaching to the black cathode.
3. Run the blot.
Blotting takes place at a given migration rate for a specified time. The
units are mA times hrs. If you need to slow the transfer down, to say
coincide with the setting up of a probe, simply decrease the current (mA)
to match the added time you require.
(mA)(hr) Std setting = (mA)(hr) New setting
Alternatively, the current can be increased to decrease the time. This
assumes that you have determined an initial mAh value that works well for
the molecules you are interested in.
A current to use for a 45 min time period is based on the area (cm.cm) of
your gel (which is the resistor in this system). A range of 0.8 to 2 mA per
square centimeter of gel.
For example, if you had a 10 x 10cm gel, the area would be 100cm
2
, so the
current range would be 80mA (0.8mAcm-
2
x 100cm
2
) to 200 mA
(2mAcm-
1
x 100cm
2
).
Blots may also be run at constant voltage. Some power supplies have
difficulty sustaining steady voltages at these low voltage settings. If you
find that voltages are fluctuating, or that the power supply shuts itself off
when set on constant voltage, use constant current settings instead.
Running the Blot
Transfer settings
