Factors Affecting the Performance of Chromatography Columns

Liquid chromatography can be operated under mild conditions in terms of pH, ionic strength, polarity of liquid, and temperature. The apparatus used is simple in construction and easily scaled-up. Moreover, many types of interaction between the adsorbent (the stationary phase) and solutes to be separated can be utilized, as shown in Table 11.1. Liquid chromatography can be operated isocratically, stepwise, and with gradient changes in the mobile phase composition. Since the performance of chromatography columns was discussed, with use of several models and on the basis of retention time and the width of elution curves, in Chapter 11, we will at this point discuss some of the factors that affect the performance of chromatography columns. 

In order to estimate resolution among peaks eluted from a chromatography column, those factors which affect N must first be elucidated. By definition, a low value of Hs will result in a large number of theoretical plates for a given column length. As discussed in Chapter 11, Equation 11.20 obtained by the rate model shows the effects of axial mixing of the mobile phase fluid and mass transfer of solutes on Hs. 

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