CombiFlash Torrent® User Manual - Isco
CombiFlash Torrent® User Manual - Isco
CombiFlash Torrent® User Manual - Isco
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Section 2 Preparation<br />
Note<br />
The System Verification procedure (section 2.15) requires a Linear<br />
gradient method.<br />
Enable Run Length Extension – When enabled, this option<br />
automatically extends the run if a peak is eluting at the end of<br />
the maximum %B gradient. This ensures that a late-eluting<br />
peak fully comes off the column and is collected.<br />
An automatic run extension is a five-minute isocratic hold<br />
added to the end of the run’s maximum %B gradient profile.<br />
During the extension, the system continues to pump the<br />
maximum %B solvent mixture. Should the system still detect<br />
a peak after an extension, the system will add another, up to a<br />
maximum of three extensions.<br />
Occasionally, compounds might come off the column once the<br />
%B returns to the minimum value at the end of a run. If the<br />
Run Length Extension is enabled, it will automatically extend<br />
the run one time to clear the column and plumbing of any<br />
remaining material.<br />
Original method<br />
Extension 1 Extension 2 Final Extension<br />
Extension 3<br />
0 5 10 15 20 25<br />
Minutes<br />
Figure 2-21 Automatic Run Extension Examples<br />
Figure 2-21 illustrates the possible run extensions. The<br />
original method was programmed to rise to the maximum %B<br />
over seven minutes, hold for two minutes and return to the<br />
minimum %B for a final minute. At nine minutes, a peak was<br />
eluting. PeakTrak extended the run, holding the %B at the<br />
maximum level for another five minutes. This also occurred at<br />
fourteen and nineteen minutes, resulting in the second and<br />
2-33