Separation of 10 Green Tea Components on an Agilent InfinityLab Poroshell 120 EC-C18, 1.9 μm Column

Significance of the Topic

Green tea contains polyphenolic catechins that strongly influence flavor and health benefits. Reliable separation of these compounds is crucial for quality control and chemical research in food and beverage analysis.

Study Objectives and Overview

This study aimed to evaluate an Agilent InfinityLab Poroshell 120 EC-C18 1.9 µm column for rapid, high-resolution separation of ten green tea components, including eight catechins (with four challenging isomer pairs), plus gallic acid and caffeine, using UHPLC conditions optimized for efficiency.

Methodology and Instrumentation used

The Agilent 1290 Infinity LC system was assembled with a low-dispersion binary pump (G4220A), autosampler (G4226A), thermostatted column compartment (G1316C), and diode array detector (G4212A). The column was a 2.1 × 50 mm Poroshell 120 EC-C18 with 1.9 μm superficially porous particles. Mobile phase A was 0.2 % formic acid in water and phase B was acetonitrile. A gradient from 5 to 16 % B over 7 min at 0.5 mL/min and 30 °C was employed, detecting at 240 nm (80 Hz). Samples contained 0.06 mg/mL of each analyte in water.

Main Results and Discussion

All ten analytes were baseline-resolved within seven minutes, achieving a minimum resolution of 2.2. The column’s high efficiency allowed clear separation of structurally similar catechins and isomer pairs in a compact 50 mm format, with peak shapes and retention reproducibility suitable for routine analysis.

Benefits and Practical Applications of the Method

This UHPLC method offers fast throughput, high resolution, and robustness for green tea quality assessment. Its short run time and reliable separation make it applicable to routine QA/QC in food testing laboratories, nutraceutical research, and compound profiling.

Future Trends and Opportunities

Advances may include coupling with mass spectrometry for structural confirmation, automating sample preparation, and applying superficially porous particle columns to other complex botanical matrices. Further miniaturization and ultra-high-pressure systems could push analysis speed and resolution even higher.

Conclusion

The Agilent InfinityLab Poroshell 120 EC-C18 column demonstrated exceptional performance in separating ten green tea components rapidly and with baseline resolution. Its combination of speed, efficiency, and reliability supports its use in routine analytical workflows.

Reference

• A. Mack, W. Long. Rapid Tea Analysis on Poroshell 120 SB-C18 with LC/MS. Agilent Technologies Application Note, publication number 5990-7824EN, 2011.
• T. Yoshida, R. Majors, H. Kumagai. High-Speed Analysis using Rapid Resolution Liquid Chromatography on ZORBAX column packed with 1.8 µm particles. J. Sep. Sci. 2006, 29(16), 2421-2432.