@article {2402,
	title = {LINEAR QUADRUPOLES IN MASS SPECTROMETRY},
	journal = {Mass Spectrometry Reviews},
	volume = {28},
	number = {6},
	year = {2009},
	note = {ISI Document Delivery No.: 515CWTimes Cited: 5Cited Reference Count: 145Douglas, D. J.},
	month = {Nov-Dec},
	pages = {937-960},
	type = {Review},
	abstract = {The use of linear quadrupoles in mass spectrometry as mass filters and ion guides is reviewed. Following a tutorial review of the principles of mass filter operation, methods of mass analysis are reviewed. Discussed are extensions of quadrupole mass filters to higher masses, scanning with frequency sweeps of the quadrupole waveform, operation in higher stability regions, and operation with rectangular or other periodic waveforms. Two relatively new methods of mass analysis the use of "islands of stability" and "mass selective axial ejection" are then reviewed. The optimal electrode geometry for a quadrupole mass filter constructed with round rods is discussed. The use of collisional cooling in quadrupole ion guides is discussed along with ion guides that have axial fields. Finally, mass analysis with quadrupoles that have large distortions to the geometry and fields is discussed. An Appendix gives a brief tutorial review of definitions of electrical potentials and fields, as well as the units used in this article. (C) 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:937-960, 2009},
	keywords = {2ND STABILITY REGION, axial fields, AXIAL-FIELD, CHARGED-PARTICLE, COLLISION-INDUCED DISSOCIATION, distorted fields, FRINGING FIELDS, ion guide, ION OPTICAL-PROPERTIES, linear, mass filter, mass scans, multipoles, OCTOPOLE FIELDS, QUADRUPOLE, quadrupole excitation, RADIO-FREQUENCY, RESOLUTION, SEPARATION MODE, STABILITY, TRAJECTORIES, VOLTAGE COMPONENT},
	isbn = {0277-7037},
	url = {<Go to ISI>://000271445200005},
	author = {Douglas, D. J.}
}
@article {3945,
	title = {Inductively coupled plasma mass spectrometry with a quadrupole mass filter operated in the third stability region},
	journal = {Journal of the American Society for Mass Spectrometry},
	volume = {8},
	number = {12},
	year = {1997},
	note = {ISI Document Delivery No.: YG420Times Cited: 18Cited Reference Count: 31},
	month = {Dec},
	pages = {1230-1236},
	type = {Article},
	abstract = {An inductively coupled plasma mass spectrometer system is described in which the quadrupole mass filter is operated in the third stability region with Mathieu parameters (a, q) approximate to (3, 3). Operation at the upper tip of this region is found to give generally better sensitivity and resolution than operation at the lower tip. A limiting resolution at half height of 4000 at m/z 59 is possible with operation at the upper tip. This resolution is insufficient to separate atomic ions from molecular ions of the same nominal mass except in favorable cases. However, operation at moderate resolution (R-1/2 = 500 to 1000) is found to give very high abundance sensitivity (>10(7)). The results suggest that the third stability region may be advantageous for specialized applications of inductively coupled plasma mass spectrometry. (C) 1997 American Society for Mass Spectrometry.},
	keywords = {ANALYZER, HELIUM, HIGH-RESOLUTION, IMPERFECT FIELDS, INTERFERENCES, ION OPTICAL-PROPERTIES, MODE, SEPARATION},
	isbn = {1044-0305},
	url = {<Go to ISI>://A1997YG42000005},
	author = {Du, Z. H. and Olney, T. N. and Douglas, D. J.}
}
