GPC Integration

The Method Setup - GPC Integration dialog is similar to the Method Setup - Integration dialog, apart from these three differences:

  • The Solvent Peak operation excludes selected integrated peaks from the evaluation. This is useful for low molecular weight impurities, which need to be integrated to get the correct baseline, however their results are not desired. GPC mode identifies the solvent peaks differently than the Standard mode - peaks are marked as solvent if they are found within the selected intervals.
  • The Group operation is not available in GPC mode. To get average values for multimodal MW distribution polymer, integrate the peaks as a single one using the Baseline Lock and Add Positive functions.
  • The Flow Marker Peak designates a peak to be used for flow rate corrected calculations. Only one peak in the whole chromatogram can be used as a flow marker, the last occurrence of such operation in the Integration Table will be used.
    • Time A shows the Max RT of the selected Flow Marker Peak (if selected from the Chromatogram) or can be manually inserted to select such peak.
    • Time B is not modifiable and shows the calculated interval width to the both sides of the interval with the Time A in the middle of such interval.
    • Value is used for the interval width calculation, i.e. how many percent of the Time A will be the width of the interval from the Time A to both sides.

Note:

The Use Flow Rate Correction checkbox must be checked in the GPC Calibration Options dialog for used calibration in addition to the selected Flow Marker, otherwise the correction will not be performed.

 

It is possible to set different settings in both Method Setup - GPC Integration and Method Setup - Integration dialogs to have the chromatogram evaluated both in the Standard and in the GPC mode.