Selecting the Optimum Integration Path

Chromeleon is capable of calculating the Optimum Integration Path within a 3D field. The calculation is performed automatically. The result can be displayed in the 3D field window of the PPA method.

• Double-click within the window and select the Draw Opt-Int-Path option on the Iso/3D Plot tab page.

   Tip:

  You may also define extraction of the optimum integration path in the Post-acquisition steps view of the PGM Editor (see Control  The PGM Editor.) Open the PGM File in which you want to define extraction of the optimum integration path, and then select the Post-acquisition steps view.

A green line in the 3D field indicates the integration path. Similar to chromatograms, it can be saved as a separate channel with variable wavelength.

• Select Extract > Opt. Int. Path to file on the View or context menu and determine the name under which the path is saved as a separate channel or accept the default name (OPTINT).

   Tip:

  In the PGM Editor, follow the steps below: Select Insert line on the context menu to add a new post-acquisition step. The New post-acquisition step dialog box is opened. Select Extract optimum integration path to open the Extract optimum integration path dialog box.

• Select Extract from all samples of current sequence or query option, if the path should be extracted for all samples of the underlying sequence or query. The shape of the path is identical for all samples!

   Tip: 

  This option is not provided in the dialog box of the PGM Editor.

 Notes: 

Chromeleon does not consider rider peaks (Type (Peak Type): Rider) when calculating the optimum integration path.

The channel extracted in this way may have baseline jumps. For distinctly absorbing solvents, they may be due to changes in the wavelength.

If the path should serve as a basis for a Wavelength Switch in future samples, the switch times and the selected wavelength values must be entered in a program with exact time specifications. This can be performed, also, by automatically inserting the data.

• Select Extract > Opt.Int.Path to clipboard on the View or context menu to copy the data to the clipboard.

• Select the Name of the channel, for which the wavelength is switched automatically in the future.

• Enter a value for the Bandwidth if several chromatograms are to be averaged to one. The bandwidth determines the range of the path. All sections of a chromatogram within this range are averaged to one chromatogram.

• Open a PGM File and insert the data at the beginning of the program (Commands view) via the Paste command.

The resulting PGM File could have the following appearance:

Enter more commands in the program to complete it. Sort it according to ascending retention times.