PDA baseline shows a negative dip in the middle of the gradient run - WKB80434

SYMPTOMS

• PDA baseline shows a negative dip in the middle of acquisition
• Appears when running sample or blank injection
• Appears when running gradient without making an injection
• New lamp installed and issue still present
• Fresh mobile phase and issue still present

ENVIRONMENT

• ACQUITY UPLC PDA Detector
• ACQUITY UPLC H-Class

CAUSE

Contaminated solvent supply glassware

Contaminated HPLC solvent supply

FIX or WORKAROUND

1. Replace contaminated glassware with clean glassware.
2. Replace contaminated HPLC solvents with new solvent.
3. Freshly prepare mobile phase for the instrument.
4. Prime the system thoroughly with new mobile phase.
5. Continue system use.

ADDITIONAL INFORMATION