This parameter sets the temperature (in degrees C) of the vaporizer in an APCI interface. It is only active if an APCI or APPI interface is installed on the LC/MS or if the multimode source is installed. If an electrospray or Agilent Jet Stream source is installed, this parameter is not visible.
| Source | Minimum | Maximum |
|---|---|---|
| APCI/APPI | Ambient | 500 °C |
| MMI | Ambient | 250 °C |
If the Multimode source is installed, the maximum Vaporizer temperature is 250 °C. In general, the higher the LC flow, the higher the Vaporizer temperature required for complete vaporization.
APPI ionization is more temperature dependent than APCI. In addition to adjusting the Vaporizer temperature for flow rate or solvent composition, you should keep an eye on the impact on ionization. The ratio of M+ : [M+H]+ can vary with temperature. A good starting point for APPI is a temperature of 275 °C. If the signal is poor, raise or lower the temperature in 25 °C increments to see if it improves.
See Also