Plate Theory and Extensions - Quantitative Analysis from Retention Measurements > Page 52


A range of concentrations of the two substances were inserted in equation (46) and a curve constructed relating retention time of the composite peak (calculated by means of a computer) to mixture composition. The results are shown in Figure 15. 


                          Courtesy of the Journal of Chromatography (ref. 1)

Figure 15. Graph of Retention Time of a Composite Peak against Composition of Mixture


The retention times of a series of mixtures of nitrobenzene and deuterated nitrobenzene were then actually measured  and the results are included as points in Figure 15. Close agreement between the experimental points and the theoretical curve is clearly demonstrated. The procedure is a practical alternative for the analysis of unresolved solute pairs, to the difficult and often tedious construction of columns having very high efficiencies. With great care and the use of modern sophisticated data acquisition and processing computers, the required accuracy and precision can be readily obtained.