Late retention times in amino acid analysis on ACQUITY H-Class system using AccQ•Tag Ultra reagents - WKB268285

SYMPTOMS

• Retention times of all amino acids are later than expected
• AMQ peak retention time is approximately 3.0 minutes (should be approximately 1.5 minutes)
• Gradient pressure trace looks different from the normal gradient pressure trace when method was working

ENVIRONMENT

• Amino acid analysis (AAA)
• AccQ•Tag Ultra
• ACQUITY H-Class

CAUSE

Clogged/plugged GPV filters

System previously run with another method and buffer.

FIX or WORKAROUND

1. Ensure that the correct mobile phases are in use for the method.
2. Change out the GPV filters.

ADDITIONAL INFORMATION