High mass calibration fails with sodium iodide (NaI) solution - WKB202813

SYMPTOMS

• Failure to create a calibration greater than m/z 2500 with sodium iodide (NaI) solution

ENVIRONMENT

• IntelliStart
• Assisted Calibration
• SYNAPT G2-S MS/HDMS
• SYNAPT G2-Si MS/HDMS
• SYNAPT G2-S
• SYNAPT G2-Si
• SYNAPT XS
• Xevo G2-S
• Xevo G2-S QTof
• Xevo G2-S Tof
• Xevo G2-XS
• Xevo G2-XS QTof
• Xevo G2-XS Tof

CAUSE

The NaI solution is old, requires vortex mixing after storage, or the concentration is less than 2 mg/mL.

In negative ion mode, mass range includes m/z 400 or less.

FIX or WORKAROUND

1. Try vortex mixing the old solution, If no improvement seen use a fresh 2-mg/mL NaI solution.
2. Set the lower limit of negative ion mode to m/z 400.

ADDITIONAL INFORMATION