Bio-Rad MicroRotofor™ Cell - Manual (Page 8)

Fig. 6. Loading sample into the focusing chamber.
4. When the sample is loaded, make sure that all the channels are filled
and that no bubbles remain. Air bubbles will disrupt the electric field,
which can lead to poor separation. To dislodge air bubbles from the
chamber, tap it gently or aspirate the sample from a channel and load it
again.
5. Dry the outside surface of the focusing chamber and seal the row of
loading ports with a piece of the sealing tape. Make sure to cover all the
ports, to not extend the tape beyond the focusing chamber, and to not
overlap the tape with the strip of tape covering the harvesting ports.
Note: Excess tape, or tape not properly positioned, interferes with the
cooling block during oscillation, which can result in leakage of sample from
the focusing chamber.
4.4 Perform the Focusing Run
1. Open the cooling block cover by unscrewing the block screw.
2. With the sealed loading ports and vents on the electrode assemblies
facing up, place the focusing assembly into the focusing station of the
chassis. Make sure the anode end (red) is to the left and the cathode
end (black) is to the right.
I. Gently push the anode end (red) of the focusing assembly into the
anode connection on the chassis until it is completely retracted
(Figure 7).
II. Lower the focusing assembly into the cooling block and slide the
cathode end of the assembly into the notch on the cathode end of
the chassis (Figure 8). If necessary, rotate the focusing assembly
until the slots on the cathode assembly align with the notch on the
chassis. Alternatively, turn power on to the oscillating motor and wait
until the notch is in a better position to connect with the focusing
assembly.
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