Fast HPLC

The aim of this module is to introduce the principles of improving chromatographic efficiency and speeding up HPLC and UHPLC separations, while highlighting the practical limitations associated with these approaches. The module explores the factors that govern separation efficiency, resolution, analysis speed, and system back pressure, with particular emphasis on modern UHPLC technologies, including sub-2 µm and superficially porous particle columns. Theoretical concepts such as the Van Deemter equation, kinetic and Poppe plots, and the contributions of mass transfer and diffusion processes will be used to explain how chromatographic performance can be optimized.

At the end of this unit, you will be able to understand the key factors that influence HPLC and UHPLC efficiency, resolution, and analysis time, and evaluate the advantages and limitations of different strategies for improving chromatographic performance. You will be able to identify and manipulate important parameters such as particle size, column dimensions, flow rate, temperature, and packing material morphology to achieve faster and more efficient separations. You will also gain an understanding of method transfer and method conversion between HPLC and UHPLC systems, including gradient elution considerations and the use of method transfer tools. Finally, you will be able to critically assess the trade-offs between speed, efficiency, resolution, pressure, and thermal effects when developing or transferring chromatographic methods.

Topics include: 

• Separation efficiency
• Back pressure and particle size
• Superficially porous materials
• Increasing resolution via improved efficiency
• Speeding up HPLC separations
• HPLC method conversion - calculator
• Transferring methods - gradient elution considerations
• Transferring methods - calculating gradient conditions
• Transferring methods - quick method transfer tools
• Efficiency
• How to change efficiency
• Effects of efficiency on resolution
• Van Deemter plots
• Eddy diffusion (the A term)
• Longitudinal diffusion (the B term)
• Mass transfer (the C term)
• Packing material - particle size
• Packing material - particle size distribution
• Column internal diameter and linear velocity
• Packing material - morphology
• Reduced diameter/sub-2 µm particles
• Superficially porous particles
• Reduced diameter non-porous particles
• Temperature
• Kinetic plots
• Poppe plots - use and description
• Poppe plots - parameters
• Impedance plots - use and description
• Thermal considerations
• Imperdance plots - parameters
• Power plots