How to Read a Chromatogram

The word "chromatogram" means a plot obtained via chromatography. Fig shows an example of a?chromatogram.?The chromatogram is a two-dimensional plot with the vertical axis showing concentration in terms of the detector signal intensity and the horizontal axis representing the analysis time. When no compounds?are eluted from the column, a line parallel to the horizontal axis is plotted. This is called the baseline. The detector responds based on the concentration of the target compound in the elution band. The obtained plot is more like the shape of a bell rather than a triangle. This shape is called a “peak”. Retention time (tR) is the time interval between sample injection point and the apex of the peak. The required time for non-retained?compounds (compounds with no interaction for the stationary phase) to go from the injector to the detector is called the dead time (t0).The peak height (h) is the vertical distance between a peak's apex and the baseline, and the peak area (A)?colored in light blue is the area enclosed by the peak and baseline.?These results will be used for the qualitative and quantitative analysis of a?sample's components.