Chromatographic Peak Terminology

1.0 OBJECTIVE

To lay down the procedure for interpretation of Chromatographic Peak Terminology

2.0 SCOPE

This SOP is applicable for the interpretation of Chromatographic Peak Terminology  Company Name.

3.0 BACKGROUND

NIL

4.0 RESPONSIBILITY

4.1 All Analytical research personnel shall follow the SOP. 

4.2 Group leader of Analytical research to ensure the procedures to be followed.      

4.3 Head Analytical research or his designee to ensure overall compliance. 

5.0 PROCEDURE

5.1 Baseline:

The response of the detector on the data system display when no sample band is passing through the detector.

5.2 Baseline Drift:

A baseline that is not perfectly horizontal, but rises or falls with time.

5.3 Peak area, A

The total area under the peak elution profile, above the baseline, and between the integration start and stop markers.

5.4 Peak height, h

The distance of a peak from its maximum response to the baseline is called peak height(h).

For a perfectly nonsloping baseline the line connecting the peak maximum and the baseline forms a 90° angle to the baseline. For sloping baselines, the connecting line is drawn between the peak maximum and an extended line from the nonsloping part of the baseline.

5.5 Peak shape

The elution profile generated by the detector once the analyte has passed through the chromatographic system. Statistical moments and other parameters (asymmetry, width, etc.) are also used to quantitatively describe the peak shape.

5.6 Peak width, w

A measure of how long it takes for the analyte profile to pass through the detector. The peak width is an important parameter because it is used to determine column efficiency (theoretical plates, N), resolution (Rs), etc. For nonsymmetrical peaks, the peak width is determined by direct measurement.

5.7 Peak Valley:

The lowest point between two adjacent peaks; the height of the valley from the baseline (as a percent of the peak heights) is a measure of how good the separation is.

5.8 Peak Tailing(T)

A peak is labelled as tailing or asymmetrical when it deviates from the ideal, symmetrical shape of a Gaussian peak.

Because peak tailing can influence the quality of a separation, it is a good idea to quantify the amount of tailing a peak has.

6.0 ANNEXURES

NIL