Bio-Rad BioLogic LP System - Manual (Page 94)

6.3 FLUSHING/CLEANING VALVES, FLOW CELLS, AND FILTERS
6.3.1 Rinsing Valves and Flow Cells
When the BioLogic LP will not be used for more than a day or two, it is important to flush salt solutions from
the valves and flow cells. Over time, salt solutions may crystallize inside of valves and flow cells, causing
damage. To flush the system:
1. Remove the column from the system and connect the column inlet tube to its outlet tube.
2. Place all buffer inlet tubes in water, and from the Pump’s Manual mode, select the Purge softkey. This
runs the pump at maximum speed.
Note: If the system will be stored for more than a week, follow the water wash with a 20% ethanol to
the water to retard microbial growth in the system.
3. As the pump runs, use the Pump’s Manual mode to select buffers “A” through “E” in turn, allowing time
for each inlet tube to clear.
4. Switch to Manual mode operation of the Valves. From the Valves manual mode screen, select the
Divert softkey. Switch the diverter valve from “Collect” to “Divert” to Waste. Allow water to flow for 15
seconds, then switch back to Collect. If an SV-3 Column Bypass valve is installed, select the Bypass
softkey from the Valves manual mode. Switch to “Bypass” mode for 15 seconds, then return to
“Column” mode.
Note: If you choose to write a Method to accomplish the procedure above, keep in mind that you will need
to manually switch the SV-3 Bypass valve.
6.3.2 Cleaning Valves and Flow Cells
If valves and/or flow cells show signs of clogging, they can be cleaned as described below. Cleaning times
may be extended for severe clogging or microbial growth.
1. Remove the column from the system and connect the column inlet tube to its outlet tube.
2. Pump 1 M NaOH (Sodium Hydroxide) through the system at 1 ml/min, for 30 minutes. If valves are
being cleaned, manually switch valve positions several times during this procedure.
3. Flush the system with water. If valves are being cleaned, manually switch valve positions several times
during this procedure.
4. Pump 1 M HCl (Hydrochloric acid) through the system at 1 ml/min, for 30 minutes. If valves are being
cleaned, manually switch valve positions several times during this procedure.
5. Flush the system with water as described in Section 6.3.1 above.
6.3.3 Cleaning the UV Optics Module’s Filters
The filter tray contains both a 280 nm and a 254 nm filter. To clean the filters, loosen the filter’s thumbscrew
and lift out the filter holder. The Filters should be cleaned only when necessary using a dry lens tissue.
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Maintenance and Troubleshooting