Theory of separation performance and peak width in gradient elution liquid chromatography: A tutorial

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Separation performance in chromatography is well-understood for isocratic elution.
• Principles governing gradient elution, particularly peak broadening and separation efficiency, are less understood.

Purpose of the Study:

• To review fundamental principles of separation performance in isocratic elution.
• To elucidate parameters affecting peak width in gradient elution.
• To discuss peak compression and extra-column dispersion in gradient chromatography.

Main Methods:

• Review of established chromatographic theory for isocratic elution.
• Analysis of factors influencing peak width and variance in gradient elution.
• Discussion of plate count and plate height in gradient mode.
• Elaboration on peak compression effects.
• Examination of extra-column dispersion impact.

Main Results:

• Isocratic elution principles provide a foundation for understanding gradient elution.
• Gradient elution introduces complexities affecting peak width and separation.
• Peak compression and extra-column dispersion are significant factors in gradient separation performance.

Conclusions:

• A comprehensive understanding of gradient elution parameters is crucial for optimizing chromatographic separations.
• Experimental evaluation methods for dispersion effects are presented.
• This tutorial aims to enhance the understanding and application of gradient chromatography.