What are good choices for needle washes in HILIC methods? - WKB84346

ENVIRONMENT

• Hydrophilic interaction chromatography (HILIC)
• Needle wash

ANSWER

For a system with a fixed loop (examples: ACQUITY UPLC Binary, ACQUITY UPLC I-Class FL):
Strong needle wash: 10:90 acetonitrile/water
Weak needle wash: 90:10 acetonitrile/water or the same as initial mobile phase (no buffer or additive)

For a system with a flow-through needle (examples: ACQUITY UPLC H-Class, ACQUITY UPLC H-Class Bio, ACQUITY UPLC I-Class FTN):
Needle wash: 50:50 acetonitrile/water (cleans exterior of needle)
Purge solvent: 90:10 acetonitrile/water (flushes interior of needle, pushes sample into flow path)

ADDITIONAL INFORMATION

715002531 - Comprehensive Guide to HILIC: Hydrophilic Interaction Chromatography