Tandem Mass Spectrometry: Electron Capture Dissociation, Collision-Induced Dissociation, Infrared Multiphoton Dissociation baixar o livro de graça

Chapters: Electron Capture Dissociation, Collision-Induced Dissociation, Infrared Multiphoton Dissociation, Blackbody Infrared Radiative Dissociation. Source: Wikipedia. Pages: 28. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: Tandem mass spectrometry, also known as MS/MS, involves multiple steps of mass spectrometry selection, with some form of fragmentation occurring in between the stages. Multiple stages of mass analysis separation can be accomplished with individual mass spectrometer elements separated in space or in a single mass spectrometer with the MS steps separated in time. In tandem mass spectrometry in space, the separation elements are physically separated and distinct, although there is a physical connection between the elements to maintain high vacuum. These elements can be sectors, transmission quadrupole, or time-of-flight. By doing tandem mass spectrometry in time, the separation is accomplished with ions trapped in the same place, with multiple separation steps taking place over time. A quadrupole ion trap or FTMS instrument can be used for such an analysis. Trapping instruments can perform multiple steps of analysis, which is sometimes referred to as MS (MS to the n). Often the number of steps, n, is not indicated, but occasionally the value is specified; for example MS indicates three stages of separation. Schematic of tandem mass spectrometryFor tandem mass spectrometry in space, the different elements are often noted in shorthand. Q - Quadrupole mass analyzerq - Radio frequency collision quadrupoleTOF - Time-of-flight mass analyzerB - Magnetic sectorE - Electric sector.The notation can be combined to indicate various hybrid instrument, for example QqQ - Triple quadrupole mass spectrometerQTOF - Quadrupole time-of-flight mass spectrometer (also QqTOF)BEBE - Four-sector (r...http: //booksllc.net/?id=77046