Measurement of Chromatographic Data

Retention distances can be measured manually on the recorder chart with a good quality rule. All distances should be estimated to the nearest 0.1 mm. The base line under each peak is constructed, using a sharply tipped pencil and the peak height taken as the distance between the constructed base line and the center of the recorder trace at the peak maximum. 

The peak width is taken as the distance between the inside edge of the recorder trace and the outside of the trailing edge of the peak at 0.6065 of the peak height. The peak widths are best measured by means of a 3X compaiitor and graticule which should be calibrated in units of 0.2 mm or less. Peak widths can then be estimated to the nearest 0.1 mm. The peak area can be taken as proportional to the product of the peak height and the peak width. 

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