1.3.1 Electrospray ionization
In electrospray ionization (ESI), a strong electrical charge is applied to the eluent as it emerges
from a nebulizer. The droplets that compose the resultant aerosol undergo a reduction in size
(solvent evaporation). As solvent continues to evaporate, the charge density increases until the
droplet surfaces eject ions (ion evaporation). The ions can be singly or multiply charged.
To operate the source in ESI mode, you fit the source enclosure with an ESI probe adaptor and
ESI probe assembly.
The standard ESI probe assembly accommodates flow rates of up to 2 mL/min, making it suitable
for LC applications in the range of 100 µL/min to 2 mL/min. To reduce peak broadening for lower-
flow-rate LC applications, such as 1-mm UPLC columns, use the optional, small-bore capillary,
which can accommodate a maximum flow rate of 200 µL/min.
1.3.2 ESCi
ESCi mode is supplied as standard equipment on the mass spectrometer. In ESCi, the standard
ESI probe adaptor is used in conjunction with a corona pin, to allow alternating acquisition of ESI
and APCI ionization data, which facilitates high throughput and wider compound coverage.
See
for further details.
1.3.3 APCI
An optional dedicated high-performance APCI interface is available. APCI 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 APCI
probe adaptor.
See
for further details.
1.3.4 Dual-mode APPI/APCI source
The optional, combined APPI/APCI source comprises an APCI probe adaptor and the APPI lamp
drive assembly. The APPI lamp drive assembly comprises a UV lamp and a repeller electrode. In
addition, a specially shaped, dual, APPI/APCI corona pin can be used. You can operate the
source in APPI, APCI, or dual mode, which switches rapidly between APPI and APCI ionization
modes.
See
for further details.
June 9, 2016, 715004990 Rev. A
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