Ghost peaks
Possible Cause | Remedial Action |
---|---|
Contamination (typically injector or column) | Flush the system including the column using an appropriate solvent (see Flushing the Pump with Persistent Contamination Only). |
Eluents are degraded, dirty or of poor purity/quality |
|
Negative peaks
Possible Cause | Remedial Action |
---|---|
Different composition of sample solvent and mobile phase | Dissolve the sample in the mobile phase. |
Air injected/vial empty | Check whether the vial is empty. Replace the vial with a filled one. |
Spikes
Possible Cause | Remedial Action |
---|---|
Electrical interferences from other system modules |
|
Column temperature significantly above boiling point of mobile phase | When developing methods, prevent the column temperature from getting significantly above the boiling point of the mobile phase. |
Solvent insufficiently degassed | Degas solvents in an ultrasonic bath. |