Chromatography Forum

Is it good practice to purge the injector before every sample set is run?

yes..

What does the purge injector actually do? does it matter what solvent is running through the system when this is being carried out for example water or mobile phase and is anybody aware of any literature on how it works.

What does the purge injector actually do? does it matter what solvent is running through the system when this is being carried out for example water or mobile phase and is anybody aware of any literature on how it works.

Purge injector washes your injector with your selected solvent. It is required use water for purging when you shift for a high buffer to high organic mobile phase to avoid salt precipitation. Then you have to purge with your mobile phase. Or shifting from normal phase to reversed phase (or vice versa) you have to use an intermediate polarity solvent first to avoid phase formation.

You especially need injector wash; when solvent is changed, bubles appears on syringe, system fills with air etc. That's why it is a good practice to purge injector frequently..