Thermo Scientific TSQ Altis, Руководство по оборудованию

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17
Scan Types
Quadrupole Capacities
72 TSQ Altis, Quantis, and Fortis Hardware Manual Thermo Scientific
Quadrupole Capacities
The mass analyzers have three rod assemblies.
1
The first and third rod assemblies, Q1 and Q3,
are quadrupoles, and the second rod assembly, Q2, is a square-profile quadrupole.
Rod assemblies can operate in either of two capacities:
• As ion transmission devices
• As mass analyzers
If you apply only RF voltage, a rod assembly serves as an ion transmission device that passes
all ions within a large range of
m/z values (that is, virtually all ions that are present).
When you apply both RF and DC voltages to a rod assembly, ions of different m/z values have
different stability profiles. This difference in stability allows the rod assembly to act as a mass
filter.
On the MS, the quadrupole rod assemblies can operate with both RF and DC voltages or
with only RF voltage. That is, Q1 and Q3 can act as either mass analyzers or ion transmission
devices. The Q2 rod assembly operates exclusively with RF voltage. Therefore, Q2 is always
an ion transmission device.
Summary of Scan Types
.
1
A rod assembly is a regular array of metal rods. See Mass Analyzers .
Table 13. Summary of scan types
Scan type Quadrupole Q1 Q2 collision cell Quadrupole Q3
Full scan (Q1) Scan
a
a
Full scan or transmission of selected ions.
Pass all ions.
b
b
Pass ions or fragments within a wide range of m/z values.
Pass all ions.
Full scan (Q3) Pass all ions. Pass all ions. Scan
SIM scan (Q1) Set
c
Pass all ions. Pass all ions.
SIM scan (Q3) Pass all ions. Pass all ions. Set
Product ion scan Set Fragment ions
d
; then
pass all fragments.
Scan
Precursor ion scan Scan Fragment ions; then
pass all fragments. Set
Neutral loss scan Scan Fragment ions; then
pass all fragments. Scan
SRM scan Set Fragment ions; then
pass all fragments. Set