Agilent Technologies 1290 Infinity II 2D-LC User Manual page 24

2 Concepts of 2D-LC
Multiple Heart-Cutting and High Resolution Sampling 2D-LC
Time-based mode in multiple heart-cutting
Figure 6
Time-based means that heart-cut times are defined in a timetable. This timetable
can be constructed according to the first dimension retention time of peaks in a
reference chromatogram. The time given in the sampling table corresponds to
the beginning of the cut parking in the reference chromatogram. The cut size is
fix and is given by t = V/F. The cut is parked by switching the valve at the time "cut
end". Ultimately, only the cut end has relevance for the method and instrument
control. The cut end is displayed in preview as a reinforced line on the right side
of the bar. If you want to move the cut you can do it graphically by moving the bar
with help of the mouse or you can change the start time in the sampling table.
You can find more info in the chapter
In MHC there is a limit of a few seconds on how close together you can place the
individual cuts. This limit is primarily dependent on the required switching time of
the 2D-LC valve. If you want to generate adjacent cuts you must use the High
Resolution mode, see
page 25. In multiple heart-cutting, loops should be overfilled (>100%). Please also
note the cut size time is related to the flow rate. If the
valve switch times are kept constant and the peak start time changes. Please
note that the reference signal from the loaded reference chromatogram
becomes invalid for a changed flow rate.
2D-LC User Guide
Time-based mode MHC
"High Resolution Sampling - Peak Parking Principles"
"Method Parameters"
1
D flow rate is changed,
on page 125.
on
24