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Published on: April 23, 2019
Performance optimizing injection sequence for minimizing injection band broadening contributions in high efficiency
A Carl Sanchez1, Jason A Anspach, Tivadar Farkas
1Phenomenex, Inc., 411 Madrid Avenue, Torrance, CA 90501, USA. carls@phenomenex.com
Journal of Chromatography. A
|February 7, 2012
Summary
The Performance Optimizing Injection Sequence (POISe) technique minimizes extra-column dispersion in UHPLC systems. This method enhances chromatographic performance by compressing analyte bands at the column head, improving peak resolution.
Area of Science:
- Analytical Chemistry
- Chromatography
Background:
- Extra-column dispersion in Ultra High-Performance Liquid Chromatography (UHPLC) limits system performance, particularly with high-efficiency columns.
- Injection and detection systems are significant sources of peak broadening in UHPLC.
Purpose of the Study:
- To present a new equation describing analyte band compression during sample introduction.
- To investigate and optimize the Performance Optimizing Injection Sequence (POISe) technique.
- To demonstrate the effectiveness of POISe across various HPLC/UHPLC platforms and column types.
Main Methods:
- Development of a new theoretical equation for sample introduction phenomena.
- Experimental investigation of the POISe technique's optimal configuration.
- Validation of POISe on different UHPLC instruments and high-efficiency columns (sub-2 μm, core-shell).
Main Results:
- A new equation demonstrates analyte band compression (isocratic focusing) proportional to retention factor (k) at the column head.
- Isocratic focusing is most effective for analytes with k values between 0.4-3.
- POISe effectively reduces injection-induced peak broadening on various UHPLC systems and columns.
Conclusions:
- The POISe technique significantly mitigates extra-column band broadening in UHPLC.
- Isocratic focusing is a key mechanism underlying the POISe technique's success.
- POISe is a versatile method applicable to diverse UHPLC setups for enhanced chromatographic resolution.
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