Waters Xevo TQD, Обзор и руководство по обслуживанию

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1 Specifications and Operating Modes
32 March 14, 2014, 715004387 Rev. B
Dual-mode APPI/APCI source
The optional, combined atmospheric pressure photoionization/atmospheric
pressure chemical ionization (APPI/APCI) source comprises an IonSABRE II
probe 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.
NanoFlow source
“NanoFlow” is the name given to several techniques that use low flow rate
electrospray ionization. The NanoFlow source allows electrospray ionization
in the flow rate range 5 to 1000 nL/min. For a given sample concentration, the
ion currents observed approximate those seen in normal flow rate
electrospray. However, for similar experiments, NanoFlow’s significant
reduction in sample consumption accompanies significant increases in
sensitivity.
The following options are available for the spraying capillary:
• Universal nebulizer sprayer (Nano-LC).
This option is for flow injection or for coupling to nano-UPLC. It uses a
pump to regulate the flow rate downward to 100 nL/min. If a syringe
pump is used, a gas-tight syringe is necessary to effect correct flow rates
without leakage. A volume of 250 µL is recommended.
• Borosilicate glass capillaries (nanovials).
Metal-coated, glass capillaries allow the lowest flow rates. Usable for
one sample, they must then be discarded.
• Capillary Electrophoresis (CE) or Capillary Electrochromatography
(CEC) sprayer. This option uses a make-up liquid at the capillary tip
that provides a stable electrospray. The make-up flow rate is less than
1 µL/min.