Towards a generic variable column length method development strategy for samples with a large variety in polarity.

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Sequential analysis of compounds with diverse polarities presents challenges in chromatography.
• Existing methods may struggle with simultaneous separation of both highly polar and non-polar analytes.

Purpose of the Study:

• To develop and validate a novel setup for sequential hydrophilic interaction liquid chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) analysis.
• To enable robust separation of compounds with a wide polarity range in a single analytical run.

Main Methods:

• Utilized an ultra-high performance LC system with two switching valves to couple HILIC and RPLC columns in series.
• Developed an interface for column coupling and incorporated solvent mixers for mobile phase compatibility.
• Implemented a sequential valve switching strategy to isolate and transfer analytes between columns.

Main Results:

• Demonstrated proof-of-concept for analyzing pharmaceuticals in wastewater and surface water samples.
• Achieved robust analyses with peak capacities intermediate to 1D and 2D separations.
• Successfully separated compounds with large variations in polarity using the sequential HILIC-RPLC approach.

Conclusions:

• The developed sequential HILIC-RPLC system offers a powerful approach for analyzing complex mixtures with diverse polarity.
• This method provides enhanced separation capabilities compared to traditional one-dimensional techniques.
• The setup is suitable for environmental analysis, particularly for pharmaceutical contaminants in water.