No response on PDA at low wavelengths - WKB80523

SYMPTOMS

• Chromatograms at low wavelengths (<215 nm) are noisy with no peak response
• Higher wavelengths respond as expected
• Low lamp energy at 230 nm

ENVIRONMENT

• Alliance HPLC System
• 2998 Photodiode Array Detector
• Autopurification

CAUSE

Contaminated mobile phase blocks light at lower wavelengths.

FIX or WORKAROUND

Re-prepare solvent in new bottles with new reagents.

ADDITIONAL INFORMATION

Mobile phase was ACN and H₂O with 0.1% formic acid. Suspect incorrect modifier or dirty glassware.