Using Column Selectivity to Optimize Resolution

A second approach to improving resolution is to adjust alpha, a. In fact, when a is nearly 1, it usually is not possible to improve resolution by adjusting ki or N. Changes in a often have a more dramatic effect on resolution than k. For example, changing a from 1.1 to 1.5 improves resolution by 267%. 

Use of column selectivity to improve chromatographic resolution showing (a) the variation in retention time with mobile phase pH, and (b) the resulting change in alpha with mobile phase pH. 

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