Collision-activate dissociation,

Collision-activated dissociation (CAD) The same process as collision-induced dissociation (CID). 

J. Shen and A. S. Al-Saeed. Study of oil field chemicals by combined field desorption/collision-activated dissociation mass spectrometry via linked scan. Ana/y Chem, 62(2) 116-120, 1990. 

Diarylfuroxans were found to give diarylacetylenes upon irradiation at 254 nm (Equation 9, Table 2). Cyclobutaphenanthrenes were also obtained when reaction was carried out in the presence of alkenes (Equation 10). The acetylenic derivative is supposed to arise by loss of (NO)2 from a diazete-iV,iV-dioxide. Unimolecular and collision-activated dissociation studies by tandem mass spectrometry also support the loss of (NO)2 from diarylfuroxans molecular ions <1997T17407>. 

DGE a AC AMS APCI API AP-MALDI APPI ASAP BIRD c CAD CE CF CF-FAB Cl CID cw CZE Da DAPCI DART DC DE DESI DIOS DTIMS EC ECD El ELDI EM ESI ETD eV f FAB FAIMS FD FI FT FTICR two-dimensional gel electrophoresis atto, 10 18 alternating current accelerator mass spectrometry atmospheric pressure chemical ionization atmospheric pressure ionization atmospheric pressure matrix-assisted laser desorption/ionization atmospheric pressure photoionization atmospheric-pressure solids analysis probe blackbody infrared radiative dissociation centi, 10-2 collision-activated dissociation capillary electrophoresis continuous flow continuous flow fast atom bombardment chemical ionization collision-induced dissociation continuous wave capillary zone electrophoresis dalton desorption atmospheric pressure chemical ionization direct analysis in real time direct current delayed extraction desorption electrospray ionization desorption/ionization on silicon drift tube ion mobility spectrometry electrochromatography electron capture dissociation electron ionization electrospray-assisted laser desorption/ionization electron multiplier electrospray ionization electron transfer dissociation electron volt femto, 1CT15 fast atom bombardment field asymmetric waveform ion mobility spectrometry field desorption field ionization Fourier transform Fourier transform ion cyclotron resonance... 

The dissociation of gas-phase ions can be a guide to the structure of the ions. There are two ways to dissociate gas-phase ions, either by collision-induced dissociation (CID) sometimes termed collision-activation dissociation (CAD) or by photodissociation. In each method, a mass selected ion is dissociated and the fragment ion (often called a daughter ion) is measured the neutral fragment cannot be experimentally observed. 

CAD Collision-activated dissociation CID Collision-induced dissociation... 

Synonymous terms used Collisional activation (CA) and collision-activated dissociation (CAD). 

Gauthier, J.W. Trautman, T.R. Jacobson, D.B. Sustained Off-Resonance Irradiation for Collision-Activated Dissociation Involving FT-ICR-MS. CID Technique That Emulates Infrared Multiphoton Dissociation. Anal. Chim. Acta 1991,246,211-225. 

Smith, R.D. Loo, J.A. Baiinaga, C.J. Edmonds, C.G. Udseth, H.R. Colhsional Activation and Collision-Activated Dissociation of Large Multiply Charged Polypeptides and Proteins Produced hy ESI. J. Am. Soc. Mass Spectrom. 1990,1, 53-65. 

Table 5.4.12 The optimum HPLC-tandem mass spectrometry (MS/MSj parameters for each BA (adapted from [31]). CAD Collision-activated dissociation, MRM multiple reaction monitoring...

Gauthier, J.W., Trautman, T.R. and Jacobson, D.B. (1991) Sustained off-resonance irradiation for collision-activated dissociation involving Fourier transform mass spectrometry. Collision-activated dissociation technique that emulates infrared multiphoton dissociation. 

Hunt, D.F., Buko, A.M., Ballard, J.M., Shabanowitz, J. and Giordani, A.B. (1980) Sequence analysis of polypeptides by collision activated dissociation on a triple quadrupole mass spectrometer. In Soft Ionization Biological Mass Spectrometry. H. Morris, ed. (London Heyden Sons Ltd.), pp. 85-109. 

A special type of mass spectrometric system is an MS/MS (e.g. [45]). In an MS/MS system the ions are generated by any of the available procedures (common El or Cl ionizations are used). The process continues with the ion separation using one of the systems previously described. A particular ion A (named parent ion) is then selected and further dissociated by collision with the molecules of a gas N (collision induced dissociation-CID or collision activated dissociation-CAD) in a reaction zone of the MS/MS system. The common reaction taking place in the CID zone can be described as follows ... 

A method that uses high performance liquid chromatography/ mass spectrometry (HPLC/MS) for the analysis of chlorinated phenoxyacid herbicides is described. During method development different techniques were used to increase both the sensitivity and the specificity of thermospray HPLC/MS for chlorinated acid herbicides. These included the operation of the instrument in the negative chemical ionization (NCI) mode initiated by discharge and the use of a wire-repeller in the ion source for efficient extraction of positive ions. Single quadrupole repeller-induced and multiple quadrupole collision activated dissociation (CAD) experiments were also performed to increase the structural information of the mass spectra. 

The collision activated dissociation (CAD) experiments in the tandem mass spectrometry (MS/MS) mode were conducted at a collision energy of 20 eV with argon at a pressure of approximately 1 mTorr. 

Collision activated dissociation (CAD) studies used argon as a collision gas at a pressure of approximately 1.4 mtorr. Collision energies were adjusted between -9V and -40V with a goal of reducing the precursor ion intensity to less than 20% of the base peak in the product spectrum. 

Goolsby, B.J. Brodbelt, J.S. Analysis of protonated and alkali metal cationized aminoglycoside antibiotics by collision-activated dissociation and infrared multi-photon dissociation in the quadrupole ion trap. J. Mass Spectrom., 35,1011-1024 (2000). 

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