Guidelines For Multimode Source Settings In Mm-Apci Mode - Agilent Technologies G1978B User Manual

Guidelines for multimode source settings in MM-APCI mode

Nebulizer pressure
pressure.
Drying gas flow
Drying gas temperature
to control the drying and to be able to maintain set point.
Vaporizer
usually works better. The vaporizer will compensate for flow rate or solvent
composition.
Corona current
~4000 V at 6 µA.
Vcap
the Vcap range.
Charging Voltage
The above set of parameters is provided as a starting point and should yield good response
N O T E
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. The four most important
parameters and the suggested optimization order are: vaporizer temperature, then capillary
voltage, then nebulizer pressure, and then corona current.
Multimode Source for 6410 Triple Quad LC/MS User Guide

Guidelines for multimode source settings in MM-APCI mode

Start at 20 psi. The signal decreases with higher nebulizer
Always set to 5 L/min (IR does the drying)
Just set to 350°C. Remember you want the vaporizer
Start at 250°C. APCI is gas phase chemistry. A higher temperature
Set to 5 µA positive or negative. The corona voltage will be
Set to 2000 V. The APCI response is usually better at the higher end of
Set to 2000.
Reference 3
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