User`s guide

Method Development
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Method Development
When you are creating a new method, you optimize the method by
performing analyses at various settings until reliable results are
obtained.
You use the Status tab to enter the desired parameters and options
and then run a few samples to evaluate the method. You then adjust
parameters accordingly and run more samples until you obtain the
desired results.
Once your method is complete, use the Save As command in the
Tools menu to save the new method. You can then update the
method at any time or create new methods based on the current one
using the Method Editor and the Edit command.
A brief description of each of the method parameters is provided in
Chapter 3. These same parameters are discussed in more detail here.
Additionally, other considerations that may affect your analyses are
covered in this chapter.
Analytical Objectives
The analytical objectives are as follows:
• During primary (tube) desorption the method should achieve
elution of 100% (or a quantitative proportion) of the components
of interest from the sample tube.
• The cold trap should retain all of the components of interest that
reach it.
• During secondary (trap) desorption, all components retained by
the cold trap must be quantitatively transferred to the analytical
column, in as narrow a band of vapor as possible.
The parameters that are manipulated to achieve the above objectives
are those common to conventional gas chromatography and are as
follows:
• temperature
• carrier gas flow
• timing
• selection of packing material