Bio-Rad Rotofor® and Mini Rotofor Cells - Manual (Page 14)

Fig. 3.5. Assembled focusing chamber.
5. Mount the assembled focusing chamber in the stand. The gear on the cathode
electrode assembly should be fully engaged with the gear on the stand. If the
focusing chamber does not slide in easily, remove it to check that all parts are
properly assembled.
6. Attach the power cord to the back of the unit and connect it to an electrical outlet.
3.4 Prepare the Focusing Chamber
With the cell mounted on the stand, rotate the focusing chamber so the 20 collection
ports, identified by the two metal alignment pins, are facing up. Cover the ports with a
piece of the sealing tape provided with the cell. Reinforce the taped ports with one of the
two acrylic cell-cover blocks, and finger tighten the screws. We recommend pre-running
the cell with pure water for the first use or after cleaning the components in the focusing
chamber with NaOH. Pre-running the cell with water for 5 minutes at 5 watts constant
power will remove residual ionic contaminants from the membrane core and ion
exchange membranes before addition of the sample.
3.5 Load the Sample
Rotate the cell so the filling ports face up. This is easily accomplished by flipping
the toggle switches to ON and HARVEST. In the harvest mode the focusing chamber
will automatically stop with the filling ports facing up and the collection ports facing
down. Fill the cell with sample through the ports using a 50 ml syringe with a 1-1/2
inch 19-gauge needle. Typically, every other port is filled, and the sample spreads into
the adjoining compartments. For the large focusing chamber, the minimum sample
volume must be sufficient to cover the cooling finger. For the mini focusing chamber
load the maximum sample volume of 18 ml.
3.6 Seal the Loading Ports
A. Mini Rotofor chamber: Place the grey rectangular, silicone gasket in the slot
containing the loading ports then place the second cell cover block over the
gasket (tape is unnecessary), and the Rotofor cell is ready for operation.
B. Standard Rotofor chamber: Seal the filling ports with only the second cell
cover block (tape is unnecessary), and the Rotofor cell is ready for operation.
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