Contamination peak on system - WKB114534

SYMPTOMS

• Contamination peak present in THC trace for solvent blanks.
• Contamination increases after subsequent injections.
• Customer replaced all components of the injection pathway (needle, seal, seal housing) with no improvement.

ENVIRONMENT

• Xevo TQ-S
• Xevo TQ-XS
• ACQUITY I-Class

CAUSE

Residue left over from the vial septa was reacting with something from the nitrogen of a peak generator.

FIX or WORKAROUND

Nitrogen from a different generator removed the contamination peak. Peak engineer needed to service or replace the generator.

ADDITIONAL INFORMATION

Waters TruView vials also resulted in far less of a contamination peak than the standard blue lidded vials, so must produce less of the septa residue that reacts with the nitrogen.