Plate Theory and Extensions - The Peak Capacity of a Chromatographic Column > Page 97

To definitively identify the presence of a peak in a chromatogram and to be able to estimate its size for quantitative purposes, the peak height must be at least 5 times the noise level. The detector sensitivity (the minimum detectable concentration) (XD), is that concentration of solute that will give a signal equivalent to twice the noise level and, so, the concentration of solute at the limiting (k') value will be 2.5XD.

Solute concentration at the peak maximum is approximately twice the average concentration. Thus, if a mass (m) is placed on the column and the peak width is  ,then,



or                                                 (78)


Now, the maximum sample volume (Vi) that can be placed on the column that would restrict the increase to less than 5% has been shown to be,