Collision-induced dissociation multiple collisions

There are multiple ways of detecting metastable and collision-induced dissociations with magnetic sector instruments. [82] In fact, the phenomenon was discovered with this particular type of mass analyzer (Chap. 2.7.1). [83,84]... 

The reactions of Mg+ with cyanoacetylene are remarkable in that while Mg is unreactive towards HCN, multiple ligation occurs for cyanoacetylene . Furthermore, there is evidence from collision induced dissociation (CID) studies that ligand-ligand interactions occur. In fact, the Mg(NC3H)4+ is especially stable, being resistant to CID. DFT calculations suggest that the semibulvalene-type structure, 4, is around 12 kcalmoU more... 

Electrospray mass spectrometry has developed into a well-established method of wide scope and potential over the past 15 years. The softness of electrospray ionization has made this technique an indispensable tool for biochemical and biomedical research. Electrospray ionization has revolutionized the analysis of labile biopolymers, with applications ranging from the analysis of DNA, RNA, oligonucleotides, proteins as well as glycoproteins to carbohydrates, lipids, gly-colipids, and lipopolysaccharides, often in combination with state-of-the-art separation techniques like liquid chromatography or capillary electrophoresis [1,2]. Beyond mere analytical applications, electrospray ionization mass spectrometry (ESMS) has proven to be a powerful tool for collision-induced dissociation (CID) and multiple-stage mass spectrometric (MSn) analysis, and - beyond the elucidation of primary structures - even for the study of noncovalent macromolecular complexes [3]. 

Collision-induced dissociation (CID), similar to other MS-MS techniques. This requires the use of a pulsed-valve collision gas introduction. Alternative approaches, i.e., very low energy and multiple excitation CID, have been developed [82]. 

FIGURE 3.1 Quadrupole ion trap mass spectrometers are capable of concatenating multiple, unique ion-processing methods during routine, robust, day-to-day operation for example, a user can combine electron transfer dissociation (ETD), proton transfer reaction (PTR), collision-induced dissociation (CID), and ion attachment (lA) in any order in but a single scan. This ability highlights how trapped-ion instruments are capable both of mass analysis and of functioning as an ion reaction vessel. 

Fig. 8.21 Collision-induced dissociation of high vibrational levels populated either by multiple IR-photon absorption (a) or by stimulated emission pumping (b)...

If fragmentation of the analyte molecules is desired, it can be caused by collision-induced dissociation (CID, Section 24.5E). In this case, tandem mass spectrometry is necessary because the first mass analyzer in the system is used to select fragments of the peptide from CID based on their overall mass, while the second mass analyzer in the system records the spectrum of the selected peptide fragment. Multiple fragments from the CID procedure can be analyzed this way. The final spectrum for each peptide fragment selected has the typical appearance of a family of ions, as shown below. 

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