Quadrupole ion guide

Thomson, B.A. 1997 McBryde Medal Award Lecture Radio Frequency Quadrupole Ion Guides in Modem Mass Spectrometry. Can. J. Chem. 1998, 76, 499-505. 

Cha, B., Blades, M. W., and Douglas, D. J. (2000). An interface with a linear quadrupole ion guide for an electrospray-ion trap mass spectrometer system. Anal. Chem. 72 5647-5654. 

The first type is a modified commercial quadrupole/TOF tandem mass spectrometer (QSTAR XL, Applied Biosystems/MDS Sciex, Concord, ON, Canada) [68] which consists of three quadrupoles (ion guide (QO), mass filter (Ql), and Q2), and an orthogonal reflectron TOF mass analyzer, as shown schematically in Figure 1.5. Although, transmission mode ion/ion reactions [66,67] were demonstrated successfully later on this instrument, ion/ion reactions were implemented initially in the mutual storage... 

Linear Ion Trap-oa-TOF Instrument A useful alternative design combines a quadrupole linear ion trap (LIT) with an oa-TOF mass analyzer [62]. This instrument consists of a short rf quadrupole ion guide, a quadrupole mass filter that operates in the rf-only mode, and an oa-TOF mass analyzer. The quadrupole mass filter is operated as an LIT to serve as an ion-accumulation and precursor-ion selection device. The mass-selected precursor is activated via a resonant excitation mode in the LIT, while the TOF instrument provides high-speed mass analysis of the resulting product ions. MS experiments have also been demonstrated with this hybrid system. A combination of QIT with an oa-TOF mass analyzer has also proven to be an effective tandem MS system [63,64]. The QIT performs tasks similar to those performed by an LIT in the LIT-oa-TOF design (i.e., its functions are ion accumulation, mass separation, and ion activation. 

Figure 8 A triple quadrupole mass spectrometer system with an electrospray ion source. S, electrospray source N2, nitrogen curtain gas O, ion sampling orifice SK, skimmer QO, RF-only quadrupole ion guide PF, delayed DC ramp prefilters Q1 mass analysing quadrupole Q2, RF quadrupole enclosed in a collision cell Q3 mass analysing quadrupole D, ion detector.

Figure 3 A schematic diagram of an orthogonal-injection TOF instrument with an electrospray ionization source. Collisional cooling is used in a quadrupole ion guide to produce a beam with a small energy spread, and a small cross section. The pressure in the ion guide is typically tens of millitorr the main TOF chamber is under high vacuum, typically torr. Ions are pulsed into...

Lunney, M. D. Moore, R. B. Cooling of mass-separated beams using a radiofrequency quadrupole ion guide. Int. J. Mass Spectrom. 1999, 190/191, 153-160. 

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