How to Reduce the Column Pressure during Liquid Chromatography?

For research use only. Not for use in diagnostic procedures.

Answer

When a new liquid chromatography (LC) method is developed, the pressure might be too high and close to the maximum pressure allowed by the hardware. It is important to address this issue before validating the method. The high pressure could be due to a clogged system or contaminated column, which can be addressed by changing the column and flushing the system. There are also method parameters that can address an LC over-pressuring situation.

The following changes can result in lower LC pressures:

1. Decreasing column length (shorter column)
2. Increasing column temperature
3. Increasing column inner diameter (ID)
4. Lowering the flow rate
5. Using a column with larger particle size (e.g., 5 µm instead of 2 µm). Smaller particle size provides more surface area and better separation, but it also results in higher pressure. Usually particle sizes of 2– 5 µm are used.

For more information on liquid chromatography parameters, follow this link on adjusting the flow rate when the column ID changes: https://sciex.com/support/knowledge-base-articles/how-to-adjust-flow-rate-in-chromatography-when-column-diameter-id-is-changed_en_us

This link discusses how column temperature affects an LC method: https://sciex.com/support/knowledge-base-articles/column-temperature-affect-on-liquid-chromatography-method_en_us