CombiFlash® R
f
Installation Guide
5-4
5.4 Flow Cell Cleaning
5.4.1 Post Separation
As a preventive measure, all default column methods finish
the separation run with a high percentage of solvent B
(Figure 5-3). This brief time (two to three column volumes) of
strong solvent flushes residual compounds from the column,
flow cell, and internal tubing.
Figure 5-3 Default post-separation column and flow cell flush
Avoid skipping the flush by stopping the run after the last
compound elutes. Skipping the flush may cause residual
compounds to build up and crystallize, which might result in:
• cross contaminating later separation runs
• higher operating pressures
• reduced flow cell lamp energy
• a noisy baseline on the absorbance trace
• frequent messages recommending flow cell cleaning
(Figure 5-4).
Allow the separation run to complete the full default column
method. If the conditions above occur repeatedly, consider
extending the flush time in the default column methods
(Tools>Edit Defaults).
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