Fluctuating Pressure on ACQUITY UPLC when starting a gradient - WKB3189

SYMPTOMS

• As the gradient is applied, pressure fluctuations increase with the increase of solvent B
• When the gradient begins, the peaks are slowly disappearing from the chromatogram while solvent B concentration increases

ENVIRONMENT

• ACQUITY Quaternary Solvent Manager (QSM)
• ACQUITY Binary Solvent Manager (BSM)

CAUSE

Air in solvent line B.

FIX or WORKAROUND

1. Thoroughly prime line B.

ADDITIONAL INFORMATION

1. Lines can be primed manually for both QSM and BSM if the priming is not enough.
2. KCS article on How to manually prime QSM can be followed and the same principle applies for BSM. The difference is that A and B can be primed seperately.