The advantages of gradient elution are enhanced peak resolution, faster analysis times, and better detectability. The major disadvantage is that the compositions of the stationary and mobile phases change during the course of the separation and column regeneration is needed before the next analysis.

Why gradient elution is generally used in chromatographic separation?

Changes in solvent strength are accompanied by a simultaneous change in selectivity for many compounds. Thus, gradient elution provides an effective means of selectivity optimization for samples with a wide retention range in a reasonable separation time with sharper peaks for all sample components.

What is the purpose of gradient elution?

Gradient elution allows the separation of a complex mixture of components that exhibit a broad range of retentivity in a single run.