This application note investigates the effects of gradient parameters on peak capacity and provides guidance on maximizing peak capacity by adjusting parameters. The study utilizes the Agilent 1290 Infinity LC system, known for its wide power range and high column backpressure tolerance. The variation of peak capacity values with flow rate, gradient time, column length, and slope of the gradient is discussed.
Peak capacity is a performance measure describing the number of peaks that can be separated during a gradient run. This document discusses how to evaluate separation performance using this metric for complex samples with unknown analytes.
The study utilizes an Agilent 1290 Infinity LC system equipped with ZORBAX Eclipse Plus columns. It evaluates the variation of peak capacity values based on changes in gradient parameters such as flow rate, gradient time, column length, and slope to provide practical guidelines for method development.
| Column dimensions (Short) | 50 mm x 2.1 mm, 1.8 µm |
|---|---|
| Column dimensions (Medium) | 100 mm x 2.1 mm, 1.8 µm |
| Column dimensions (Long) | 150 mm x 2.1 mm, 1.8 µm |
| Binary Pump Backpressure Limit | up to 1200 bar |
| Flow Rate Range (Short Column) | 0.2 to 2.0 mL/min |
| Flow Rate Range (Medium Column) | up to 1.4 mL/min |
| Flow Rate Range (Long Column) | up to 1.0 mL/min |
| Column Temperature | 50°C |
Peak capacity is a performance measure describing the number of peaks that can be separated during a gradient run with a certain resolution.
Increasing the flow rate generally increases peak capacity; for example, increasing from 0.2 mL/min to 2.0 mL/min can raise peak capacity from about 100 to about 250.