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Functional Description
14
Surveyor MSQ Plus Hardware Manual
Thermo Scientific
A functional block diagram of the Surveyor LC/MS integrated system with a Surveyor
LC Pump, Surveyor Autosampler, and a Surveyor MSQ Plus MS detector is shown in
. A sample transfer line connects the Surveyor LC to the Surveyor MSQ Plus MS
detector. The Surveyor LC system is usually installed to the left of the Surveyor MSQ Plus
MS detector to minimize the length of tubing required to connect the outlet from the LC to
the inlet of the mass spectrometer. Liquid chromatography systems supplied by other
manufacturers can also be integrated with the Surveyor MSQ Plus MS detector.
Samples are injected by an autosampler into the mobile phase stream provided by the
LC pump. As the stream passes through the LC column, the sample mixture partitions
between a solid stationary phase of large surface area and the liquid mobile phase. The
molecular structure of each component of the mixture determines when each component
elutes from the column.
The outlet of the LC column can be directly connected to a UV detector, the MS detector, or
both with a split flow tee. For instructions on connecting a split flow tee, see
“Optimizing the LC Conditions.”
Upon entering the API source of the MS detector,
preformed sample ions are desolvated by electrospray ionization (ESI) or sample molecules are
desolvated and ionized by atmospheric pressure chemical ionization (APCI). The vacuum
system draws the vaporized molecules and ions into the ion optics. The ion optics focus and
accelerate the resulting sample ions into the mass analyzer, where they are analyzed according
to their mass-to-charge ratios. As the mass analyzer ejects sample ions, they are detected by an
ion detection system, producing an ion current signal. The ion current signal, which is
proportional to the number of ions in solution, is received and amplified by the system
electronics and then passed on to the data system for further processing, storage, and display.
Figure 8.
Functional block diagram of the Surveyor MSQ Plus LC/MS system
Autosampler
LC
pump
API
source
Ion
optics
Mass
analyzer
Ion
detection
system
V
acuum
system
Instrument
control
electronic
assemblies
Reference
inlet
system
Printer
Personal
computer
V
ideo
monitor
Column
Su
r
veyo
r
MSQ Plu
s
MS detecto
r
Data
s
y
s
tem
Narrow, double-headed arrows represent electrical connections.
Broad, single-headed arrows represent the flow of sample molecules through the instrument.