The contaminations could be eluting from the autosampler. To reduce the contaminations in the FIA blank injections, perform the following procedure:
- Install 10% MeOH in water on your FIA
line and flush out tubing for 20 min at 0.5 mL/min
- Install strong wash (equal parts
MeOH:ACN:Water:IsoPropanol) on the FIA line and flush for 20 min at 0.5 mL/min
- Install FIA mobile
phase again and flush for 20 min at 0.5 mL/min
- Use wash solvent as solvent
and sample for injections (e.g. put wash sample in a vial).
Perform 20 injections using
the FIA1 method using wash solvent as solvent and for injections (e.g. put wash
sample in a vial).
If
it still looks bad, try replacing the peek tubing between the column oven and
source.
Clean
the curtain plate and replace the ESI capillary.
For further troubleshooting, please contact support@biocrates.com.
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