Silanol masking capacity

By inspection of the loading plot obtained (Fig. 5) and the contribution of variables to the selected PC axis (Table 4), we deduce that PCI mainly consists of asymmetry and reduced height, and PC2 of retention. Thus, differences between NAU, ABZ, and DIS are, for example, mainly due to differences in retention. Nevertheless, most of the variance is explained by PCI, meaning that column positions along this axis can be used as ranking criteria of stationary phases in relation to their silanol masking capacity. 

This optimization entails a large reduction in the number of measured chromatographic parameters per stationary phase 252 (7 compounds x 3 injections X 3 columns x 2 mobile phases x 2 chromatographic parameters) instead of 1890 (14 compounds x 3 injections x 5 columns x 3 mobile phases x 3 chromatographic parameters). Furthermore, in the analysis of basic compounds, only the mobile phase at pH 7.0 is effectively necessary to achieve a good evaluation of silanol masking capacity of chromatographic supports. A second mobile phase (at pH 3.0) may be required only when an assessment of the hydrophobic properties of stationary phases is needed. 

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