Packed column optimization strategies

Moreover, the effect of pH on a particular compound s retention needs to be determined first before exploring the retentivity and selectivity of different columns. The strategy and choice of the optimal pH for analysis was discussed in Chapter 4 and is further reinforced in the case studies within this chapter. After the optimal pH is chosen for the separation and the gradient has been optimized on a particular column and the optimal selectivity still has not been achieved between critical pairs, then a column screening can be performed. For method column screening, generally columns with 10-cm or 5-cm X 3.0-mm i.d. could be used that are packed with 3-pm particles. Implementation of a column switcher that can use six different types of stationary phases such as two types of C18 from different vendors, phenyl, two polar embedded, and pentafluorphenyl is suggested. 

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