High Pressure Issue in HPLC

Pressure issue can be two types: High Pressure and Low Pressure

Let’s talk about High Pressure issue: 

HPLC system is having different modules or component like Pump, Sampler, Column Compartment, Detector etc. These modules are interconnected with some kind of metal or different material Tubing/Capillaries. 

These tubing is having very narrow id like 0.18 mm, some case 0.12 mm or 0.17 mm also. If some particles stuck up inside this tubing, it will create partial or complete blockage and resulting high pressure. Generally, Pressure measurement in HPLC is done in Pump. Pump will measure back pressure.

Due to blockage, flow will not move further and HPLC system will show high pressure due to blockage in Flow path. Sometime due to partial blockage, system pressure will not go beyond limit, but it will be more than normal condition.

If you are facing high pressure issue in system, following things need to be checked:

• Quickest way to identify is to open Purge Valve and if it is releasing pressure that means there is no issue till purge valve in pump module.

• Some HPLC is having in-built filter in Pump. If that is having blockage, it will generate high pressure.

• You need to remove tubing from flow path component one by one, by removing tubing and you can find out which portion of system is generating high pressure. 

• You can remove Column "In" tubing also to check whether Column is generating high pressure or different component.

• To avoid frequent high-pressure issue, make sure to filter mobile phase properly as per requirement given in specific hardware specification. Need to filter Sample also before filling Vial. Replace Mobile Phase Suction filter in Bottle timely.

• Once Analysis is completed make sure to flush System and Column with appropriate Solvent as per guideline/SOP. It is always good to flush system weekly also.