If an analysis shows peaks with pronounced tailing, one of the following may be the cause:
Active sites can cause a number of symptoms. The most common symptom is peak tailing. Others symptoms include peak fronting and increased retention times.
Replace the injection port liner with a new, deactivated liner.
Make sure the liner is installed properly. Column fragments in the liner can cause peak tailing.
Replace the injection port seal.
Remove the column from the injection port. Break off the first 10 cm. Reinstall the column in the injection port.
See the documentation supplied with the GC for help with injection port maintenance.
If the injection expands to a volume greater than the volume of the liner, it can skew the peak to the left (peak tailing) or right (peak fronting). Decrease the injection size.
An injection port temperature that is too high or too low can cause peak tailing. Increase or decrease the injection port temperature 25 to 50 degrees C and try again.
CAUTION! Do not exceed the temperature limit of the capillary column. Doing so can ruin the column.
Insufficient carrier gas (column) flow can cause both peak tailing and peak fronting. Try raising the flow. Do not exceed 2.0 mL/minute if your MSD is equipped with a diffusion pump or 4.0 mL/minute if your MSD is equipped with a turbomolecular pump.
Increase the temperature of the GC/MSD interface (Thermal Aux #2) and see if the tailing is reduced. If it is continue to adjust the temperature until you find the optimum setting.
CAUTION! Do not exceed the temperature limit of the column.
Increase the temperature of the ion source and see if the tailing is reduced. If it is continue to adjust the temperature until you find the optimum setting.