Teledyne ACCQPrep HP125, Инструкция по установке и эксплуатации

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ACCQPrep HP125
Section 5 PeakTrak
5-31
to add a point. You can then drag the new point to the desired
location. Delete a point by clicking the D
ELETE
button and then
clicking the undesired inflection point.
The above methods work in the M
AIN
window and M
ETHOD
E
DITOR WINDOW
. Alternatively, you can modify, add, insert, and
delete points using a tabular view on the M
ETHOD
E
DITOR
window. Click the E
DIT
G
RADIENT
button to open this view, then
use the controls to modify the settings. Click the E
DIT
G
RADIENT
button again to close the table view.
5.3.4 Real-time Gradient
Editing
The gradient shape can be changed during the run. Any time
after the fraction collector has positioned the drop former over
the first tube, click and drag the points on the gradient plot area
of the M
AIN
window. You can also add or remove points by
clicking the I
NSERT
or D
ELETE
point buttons. The I
NSERT
button
allows you to add a single point when you click on the gradient
profile. Repeat this action to add more points. The D
ELETE
button allows you to remove a single point when you click on it.
Note
Only the portion of the gradient that has not yet occurred dur-
ing the run can be modified.
5.3.5 Bypassing the
Injection Loop
The L
OOP
B
YPASS
button is used to override the position of the
Prep injection loop. During normal operation the loop is placed
into the flow path ahead of the column after the equilibration is
completed. It remains in this position for the remainder of the
separation. This feature allows you to remove the loop from the
flow path and is useful for manually stacking injections when
doing an isocratic separation. It will require you to perform suffi-
cient method development to know when all of the compounds
elute from the column.
As a simple example, assume that a separation is developed with
2 compounds that elute at 5 and 10 minutes. At the 5 minute
point of the separation, the sample loop can be removed from the
flow path and loaded with another sample of the same materials.
The loop can then be placed into the flow path at the 6 minute
point. In this scenario, the first compound will elute at 5
minutes, the second compound will elute from the column at 10
minutes. The first compound in the second injection will elute at
11 minutes (6 minute injection time plus 5 minutes to elute) and
the second compound from the second injection will elute at 16
minutes.
In this simple example, the 2 injections can be separated in 16
minutes instead of 20 minutes. The process can be repeated as
needed in increase system throughput. While isocratic separa-
tions may typically be slower than a gradient separation, you are
also able to eliminate the time required for column equilibration
after a gradient separation.