Using licorice, a licorice hydrolysis product, and commercial licorice samples, high-resolution reversed-phase HPLC analytical studies showed that resolution and throughput using a ZORBAX 1.8-µm column greatly exceeded that obtained using the conventional 5.0-µm column.
This document is an application note by Agilent Technologies comparing the performance of conventional ZORBAX SB-C18 columns with the newer Rapid Resolution High-Throughput (RRHT) 1.8-µm columns. The study focuses on the separation of glycyrrhizin and its hydrolysis product, glycyrrhetinic acid, from licorice root extracts.
The note details experimental conditions using an Agilent 1200 Series Rapid Resolution System, including mobile phases, gradient elution parameters, and flow rates. It presents chromatographic data showing that the 1.8-µm column achieves similar resolution to the conventional 5.0-µm column but with significantly shorter run times and higher peak capacity, making it suitable for analyzing complex natural product mixtures.
| Column Type 1 | ZORBAX StableBond (SB)-C18, 4.6 mm x 250 mm, 5 µm |
|---|---|
| Column Type 2 | ZORBAX SB-C18 RRHT, 4.6 mm x 150 mm, 1.8 µm |
| Instrument | Agilent 1200 Series Rapid Resolution System |
| Detector | Multiple wavelength detector (MWD), 254 nm/100 BW, 460 nm reference |
| Mobile Phase A | 1% Acetic acid in water |
| Mobile Phase B | 1% Acetic acid in acetonitrile |
| Flow Rate | 1.0 mL/min |
| Temperature | Ambient |
The RRHT column allows for more rapid separations with virtually the same resolution, saving about 40% in time.
The calculated peak capacity for the 1.8-µm column was 442, which is over 50% higher than the 290 capacity of the 5-µm column.
The study used glycyrrhizic acid ammonium salt and 18-beta-glycyrrhetinic acid purchased from Sigma Aldrich.