Tangent skimming, integration

Figure 1.19. Possible error sources in the integration of chromatographic peaks. (A) Tangent skimming and perpendicular drop methods to assign peak boundaries for fused peaks (B) the misproportionation of the true peak area between two incompletely separated peaks of different size (C) loss of peak area due to integration with a threshold value set too high and (D) variation of peak area due to differences between the real sloping baseline and the interpolated integrator baseline.

Electronic or Computing Integrators—Proof of separation and response equivalent to that for a recorder is required for displays other than by chart recorder. Baseline tracking with tangent skim peak detection is recommended. 

Recorder—Electronic integration is required. Tangent skimming capabilities are required because of the difficulty in fully separating impurities from p-xylene. 

Electronic Integration, with tangent skim capabilities is recommended. 

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