Troubleshooting Problems with Injector in HPLC

The injector is a vital component of a High-Performance Liquid Chromatography (HPLC) system that permits the sample to be injected into the chromatographic column. It is in charge of the injection's accuracy and precision, which has an impact on the system's data quality. Any injector problems might result in poor performance, reduced sensitivity, or even system failure. In this post, we will go over some of the most frequent injector problems and how to troubleshoot them in an HPLC system.

Problem #1: Inconsistent injection volumes

Inconsistent injection volumes might be caused by a clogged injector, a broken or worn-out septum, or an incorrectly set injection volume. To begin troubleshooting this issue, consider cleaning the injector with a suitable solvent. If cleaning the injector does not solve the problem, replace the septum or adjust the injection volume. Check that the injection volume is properly configured and that the sample loop is clean.

Problem #2: Ghost peaks

Ghost peaks are peaks that show on a chromatogram even when no sample is present. This issue can develop for a variety of causes, including carryover from a prior injection, injector contamination, or a broken or worn-out septum. To begin troubleshooting this issue, consider flushing the injector with a suitable solvent to remove any leftover sample. If this does not work, replace the septum and carefully clean the injector.

Problem #3: Poor injection precision

Poor injection precision can occur due to several reasons, including an improperly adjusted injection volume, contamination of the injector, or a damaged or worn-out septum. To troubleshoot this problem, first, check the injection volume setting and make sure that it is correct. If this does not work, clean the injector thoroughly and replace the septum.

Problem #4: Leaking injector

A leaking injector can occur due to several reasons, including a damaged or worn-out septum, a loose connection, or a cracked injector body. To troubleshoot this problem, first, check the septum and make sure that it is correctly installed and not worn out. If this does not work, check the connections between the injector and the column to make sure that they are tight. If the problem persists, replace the injector body.

Problem #5: Sample overload

Sample overload can occur when the amount of sample injected into the system is too high, leading to peak broadening or loss of resolution. To troubleshoot this problem, reduce the sample size, adjust the injection volume, or dilute the sample before injection.

Troubleshooting Problems with Injectors in HPLC

These problems are usually detected while you are using the injection valve.

Manual Injector, Hard to Turn