Teledyne ACCQPrep HP125, Installation And Operation Manual

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ACCQPrep HP125
Section 6 Maintenance
6-4
6.4 Flow Cell Cleaning
6.4.1 Post Separation As a preventive measure, all default column methods finish the
separation run with a high percentage of solvent B (Figure 6-2).
This brief time (one to six column volumes) of strong solvent
flushes residual compounds from the column, flow cell, and
internal tubing.
Figure 6-2 Default post-separation column and flow cell
flush
Skipping the post-separation flush may cause residual com-
pounds 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 6-3).
Typically, chemists S
TOP
and then T
ERMINATE
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 flush, or run a high percentage
of %B solvent through the system for a few minutes at the end of
each day.
If the separation runs always continue through the flush and the
conditions still occur frequently, edit the D
EFAULT COLUMN
METHOD
s to extend the flush duration.
CAUTION
Do not use polar, basic solvent systems with silica column
media. These solvent systems may break down the silica
structure, possibly causing obstructions in the flow path.
Examples of such solvent systems include, but are not limited
to, those containing more than 20% methanol with ammonia.