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Ion mobility spectrometry-mass spectrometry (IMS/MS or IMMS) is a technique where ions are first separated by drift time through some neutral gas under an applied electrical potential gradient before being introduced into a mass spectrometer. [43] Drift time is a measure of the collisional cross section relative to the charge of the ion.
Schematic of field desorption ionization with emitter at left and mass spectrometer at right. Field desorption (FD) is a method of ion formation used in mass spectrometry (MS) in which a high-potential electric field is applied to an emitter with a sharp surface, such as a razor blade, or more commonly, a filament from which tiny "whiskers" have formed.
Ion trajectories in an Orbitrap mass spectrometer. In mass spectrometry, Orbitrap is an ion trap mass analyzer consisting of an outer barrel-like electrode and a coaxial inner spindle-like electrode that traps ions in an orbital motion around the spindle.
When a beam of high energy ions is used instead of atoms (as in secondary ion mass spectrometry), the method is known as liquid secondary ion mass spectrometry (LSIMS). [ 5 ] [ 6 ] [ 7 ] In FAB and LSIMS, the material to be analyzed is mixed with a non-volatile chemical protection environment, called a matrix , and is bombarded under vacuum ...
Both, the first mass analyzer and the collision cell are continuously exposed to ions from the source, in a time independent manner. [4] It is once the ions move into the third mass analyzer that time dependence becomes a factor. [4] The first quadrupole mass filter, Q1, is the primary m/z selector after the sample leaves the ionization source.
[1] [2] Mass spectra is a plot of relative abundance against mass-to-charge ratio. It is commonly used for the identification of organic compounds from electron ionization mass spectrometry. [3] [4] Organic chemists obtain mass spectra of chemical compounds as part of structure elucidation and the analysis is part of many organic chemistry ...
A mass-selecting quadrupole and collision quadrupole with time-of-flight device as the second mass selection stage is a hybrid known as a quadrupole time-of-flight mass spectrometer (QTOF MS). [ 8 ] [ 9 ] Quadrupole-quadrupole-time-of-flight (QqTOF) configurations are also possible and used especially the mass spectrometry of peptides and other ...
Selected reaction monitoring (SRM), also called multiple reaction monitoring (MRM), is a method used in tandem mass spectrometry in which an ion of a particular mass is selected in the first stage of a tandem mass spectrometer and an ion product of a fragmentation reaction of the precursor ions is selected in the second mass spectrometer stage ...