Teledyne CombiFlash EZ Prep, User Manual

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CombiFlash® Rf
+
User Manual
8-6
8.5 Flow Cell Cleaning
8.5.1 Post Separation
As a preventive measure, all default column methods finish
the separation run with a high percentage of solvent B
(Figure 8-3). This brief time (two to three column volumes) of
strong solvent flushes residual compounds from the column,
flow cell, and internal tubing.
Figure 8-3 Default post-separation column and flow cell flush
Skipping the post-separation 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 8-4).
Typically, chemists Stop and then Fast Forward the run after
the last compound elutes. This action skips the
post-separation flush. If any of the above conditions appear,
consider allowing some of the runs to continue through the
0
25
50
75
100
Gr
adient % Solv
ent B
Time or Column Volumes
Initial %B
Next Run Initial %B
End of
Separation
End of
Run
Flush
Separation
Gradient