PDA-100 Photodiode Array Detector
5-2
Doc. 031644-02 9/03
5.2
Cleaning the Flow Cell
Film deposits on the flow cell windows may cause excessive baseline noise or
high absorbance offset.
1. Pump methanol through the cell for 20 to 30 minutes at 1.0 mL/min.
2. Pump deionized water through the cell for 20 to 30 minutes at 1.0 mL/min.
If the procedure above does not clean the cell, follow these steps:
1. Disconnect the liquid lines from the cell in and out connections.
2. Connect a luer adapter to the cell in connection.
3. Using a syringe, flush the cell with a succession of deionized water, acetone,
and 3 M HNO
3
.
4. Flush the cell with deionized water for 20 to 30 minutes at 1.0 mL/min.
5. Reconnect the cell liquid lines.
5.3
Removing Trapped Air from the Flow Cell
Trapped air bubbles in the flow cell may cause pulsations of the baseline or
random noise and low readings.
Flush the cell with methanol for 20 minutes. If this does not remove the trapped
air, follow these steps:
1. Disconnect the waste line from the cell. Also disconnect the backpressure
device.
2. Using a small syringe, push 3 to 5 mL of methanol through the cell. Or,
bypass the column and pump methanol through the system at 1.0 mL/min.
3. Reconnect the waste line and backpressure device.
