Amersham Biosciences Hoefer DALT, User Manual, Page: 28 / 70

Preparing the DALT Tank for Electrophoresis Hoefer DALT System
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Amersham Biosciences
Preparing the DALT Tank for Electrophoresis
N
OTE
Position the DALT Tank near a sink for easy rinsing and draining.
A magnetically coupled centrifugal pump, mounted on the back of the DALT Tank
provides buffer circulation across the heat exchanger tubes and the gels in the center
chamber.
I
MPORTANT
Never lift or move the tank by holding the pump or the tubing at the
back of the tank.
The heat exchanger consists of four ceramic tubes below the buffer circulation flutes. It
is quite robust, but dropping a heavy, sharp object into the tank could damage it. A
cracked heat exchanger can leak coolant into the tank or buffer out of the tank, either
of which might be hazardous.
Connecting a Refrigerated Circulating Bath
To maintain a constant buffer temperature, connect a refrigerated circulating bath, such
as the MultiTemp III, to the heat exchanger fittings at the back of the DALT Tank. The
pump in the bath circulates chilled liquid through the alumina heat exchanger. The
pump on the DALT Tank circulates the buffer in the central chamber over the heat
exchanger and the gel cassettes, ensuring even gel temperature during the run.
Note For quick and easy
connections, install Quick-
fit connectors with valves
in the line.
1. Prepare two lengths of vinyl or silicone tubing. Slide hose clamps (4 total) onto each
end of two lengths of tubing. Attach one end of each length of tubing to the Quick-
fit connector attached to the heat exchanger port. Attach the free ends of each
length of tubing to the circulator bath ports; one to the inlet and the other to the
outlet. Secure the connections to the Quick-fit connectors and the circulating water
bath with the hose clamps.
2. Set the circulating bath temperature to 10 °C.
I
MPORTANT
The circulator pump must not generate a pressure greater than 0.7 bar
(10 psi) above atmospheric pressure.
If you use a temperature below 10 °C, use a 50/50 water/ethylene glycol solution in
the circulating bath. Do not use any organic solvent other than 50/50 ethylene
glycol/water as a coolant. Most solvents, including methanol and isopropanol, will
craze the plastic parts of the heat exchanger.
WARNING Do not use automotive antifreeze solution. Ethylene glycol is toxic
and may be fatal if ingested, inhaled or absorbed through the skin.
Filling the Tank with SDS Electrophoresis Buffer
Because the DALT Tank has its own circulating pump, you can make the tank buffer
within the tank itself. The size and number of the cassettes used determine the amount
of SDS electrophoresis buffer needed to cover the cassettes. You can run any number of