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1200 Series Handheld Control Module Users’s Guide
12
Running an Injector Program
Creating an Injector Program
Creating an Injector Program
The injector program is part of the method. The injector program screen can
be accessed using the Inj.
Program
button [
F3
] in the
Autosampler
Settings
screen.
This section describes an injector program to do sample preparation involving
a precolumn derivatization reaction. This is required when the analytes lack
chromophores and in their original chemical structure cannot be detected
with the required sensitivity.
To create this injector program you will:
•
set the LC system to the default settings
•
modify the injector program settings in the Inj. Program screen, the other
settings will remain with their default values, and
•
save the method with the name DERIV.
When the method called DERIV is started, the program is executed followed by
the analytical run.
The first step of the program involves drawing derivatization reagent into the
needle capillary, followed by sample and then reagent again. To ensure the
reagent and sample react efficiently, the plunger in the metering device of the
autosampler is moved back and forth. This mixes the sample and reagent as
they travel up and down the capillary. Following mixing, the derivatization
requires a pause to allow the sample and reagent to fully react, before the
derivatized sample is injected onto the column.