Waters Xevo TQD, Overview And Maintenance Manual

Page: 62 / 250

3 Changing the Mode of Operation
62 March 14, 2014, 715004387 Rev. B
ESCi mode
To run ESCi applications, you must fit an ESI probe and corona pin to the
ESI/APCI/ESCi source enclosure.
See “Installing the ESI probe” on
page 58 , “Installing the corona pin in the
source” on page 93 , and “IntelliStart Fluidics System” on page 34 .
Optimizing the ESI probe for ESCi operation
See the mass spectrometer’s online Help for details on how to optimize the ESI
probe for ESCi operation.
APCI mode
APCI mode, an option for the mass spectrometer, produces singly charged
protonated or deprotonated molecules for a broad range of nonvolatile
analytes.
The APCI interface consists of the ESI/APCI/ESCi enclosure fitted with a
corona pin and an IonSABRE II probe. Mobile phase from the LC column
enters the probe, where it is pneumatically converted to an aerosol, rapidly
heated, and vaporized or gasified at the probe tip.
APCI mode:
Hot gas from the IonSABRE II probe passes between the sample cone and the
corona pin, which is typically operated with a discharge current of 5 µA.
Mobile phase molecules rapidly react with ions generated by the corona
IonSABRE II probe
Sample cone
Corona pin