Strong contaminant peak at m/z 214 - WKB3527

SYMPTOMS

• Strong contaminant peak at m/z 214 in positive ion polarity
• Positive ion sensitivity specification fails
• No contamination is observed when infusing each solvent directly to the MS

ENVIRONMENT

• Xevo G2-XS
• Xevo G2-S
• Xevo G2
• Xevo QTof

CAUSE

Nitrogen Supply is contaminated. Ion suppression behavior of the m/z 214.

FIX or WORKAROUND

1. Replace the nitrogen supply source including associated tubing connected to the mass spectrometer.
2. Monitor the m/z 214 signal is decreasing overtime. However the longer an MS instrument has been exposed to the contamination, the longer it might take to flush the contaminant peak out of the system.
3. Reassess the MS sensitivity performance and verify that it has recovered from the contamination.

ADDITIONAL INFORMATION

m/z 214 signal corresponds to a plasticizer, n-butyl benzenesulfonamide or n-BBS,  which causes ion suppression in positive-ion polarity preventing the mass spectrometer from meeting the sensitivity specification requirements.

MS/MS gives major m/z 158 due to the loss of n-butyl.

If the instrument has been exposed to the contamination for a prolonged period of time the gas handling assembly may require troubleshooting.