Principles and Practice of Chromatography - Chromatography Nomenclature > Page 11

Chromatography Nomenclature

Chromatography nomenclature has evolved over the years but it was not until the late 1950s that the various terms used for the characteristics of a chromatogram were rationalized. A summary of the nomenclature is shown diagramatically in figure 4. The various terms are defined as follows.

Figure 4 The Nomenclature of a Chromatogram.

The baseline is any part of the chromatogram where only mobile phase is emerging from the column.

The peak maximum is the highest point of the peak.

The injection point is that point in time/position time when/where the sample is placed on the column.

The dead point is the position of the peak-maximum of an unretained solute.

The dead time (to) is the time elapsed between the injection point and the dead point.

The dead volume (Vo) is the volume of mobile phase passed through the column between the injection point and the dead point.