52
Multimode Source for 6410 Triple Quad LC/MS User Guide
3
Reference
Guidelines for multimode source settings in MM-ES+APCI mode
Guidelines for multimode source settings in MM-ES+APCI mode
Drying gas flow
Always set to 5 L/min (IR does the drying)
Nebulizer pressure
Start at 40 psi. You will use the nebulizer pressure and the
corona current to balance ESI and APCI. A higher nebulizer pressure results
in more ESI. A lower nebulizer pressure results in more APCI.
Drying gas temperature
Set to 300°C. Remember you want the vaporizer to
control the drying and to be able to maintain the set point.
Vaporizer
Start at 200°C. A higher temperature usually works better for
MM-APCI. MM-ESI is usually unaffected except for sodium adduction. The
vaporizer will compensate for flow rate or solvent composition.
Capillary Voltage
Set to 2000 V. You are balancing ESI and APCI response. A
setting of 2000 is a good compromise.
Corona current
Set to 1 µA for positive or negative polarity. More corona
current will reduce the ESI signal and increase the APCI signal.
Charging Voltage
Set the charging voltage to 2000 V.
N O T E
The above set of parameters is provided as a starting point and should yield good response
for many analytes. To obtain a specific response, i.e., high sensitivity detection of a
compound or class of compounds, or a balanced response to a wide variety of compound
classes, these parameters and the LC mobile phase composition should be examined
further using traditional techniques for optimizing a method.
