Multiple Broad Linear Calibration

This method utilizes Broad Standards with solely known Mn and Mw values. The Hamielec method assumes that the calibration can be approximated by straight line in the area of Broad Peak being calibrated. The software uses numeric Newton method for calculating A and B parameters of linear calibration curve of the given peak. Accuracy of Mn and Mw values calculated is about 1 e-5 in comparison to Mn and Mw values documented for the standard. Multiple Broad Peaks can be used subsequently to extend the area of calibration reliability.

Three points for each peak are used to construct a resulting calibration curve. One point is peak Max RT, the others are computed by Peak Height value entered in the GPC Calibration Options dialog.

GPC Calibration (Broad Linear)

After selecting the calibration type, a standard chromatogram can be opened. The Add Broad Peak icon will transfer the integrated peak data to the Calibration Summary Table, setting a new standard number and creating a new line for each peak.

For multi-signal standards the Set Broad Peak icon is used for transferring the peak data on subsequent signals to calibration. Operation is performed only for peaks with Std. No. value equal to current Std. No. indicated on the Window toolbar of the Calibration window.