We have been working on this technology for a decade. We have made many improvements that have increased fragmentation efficiency to where the technology is now practical in common mass spectrometers.
Our Publications Describing the Technology:
1. Valery G. Voinov, Samuel E. Bennet, Douglas F. Barofsky (2015) Electron-Induced Dissociation of Peptides in a Triple Quadrupole Mass Spectrometer Retrofitted with an Electromagnetostatic Cell. J Am Soc Mass Spectrom. 2015 Epub PMID:25652934
Dissociation of peptides induced by interaction with (free) electrons (electron-induced dissociation, EID) at electron energies ranging from near 0 to >30 eV was carried out using a radio-frequency-free electromagnetostatic (EMS) cell retrofitted into a triple quadrupole mass spectrometer. The product-ion mass spectra exhibited EID originating from electronically excited even electron precursor ions, reduced radical cations formed by capture of low-energy electrons, and oxidized radical cations produced by interaction with high-energy electrons. The spectra demonstrate, within the limits of the triple quadrupole's resolving power, that high-energy EID product-ion spectra produced with an EMS cell exhibit essentially the same qualitative structural information, i.e. amino acid side-chain (SC) losses and backbone cleavages, as observed in high-energy EID spectra produced with a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. The levels of fragmentation efficiency evident in the product-ion spectra recorded in this study, as was the case for those recorded in earlier studies with FT ICR mass spectrometers, is currently at the margin of analytical utility. Given that this shortcoming can be remedied, EMS cells incorporated into QqQ or QqTOF mass spectrometers could make tandem high-energy EID mass spectrometry more widely accessible for analysis of peptides, small singly charged molecules, pharmaceuticals, and clinical samples.
2. Voinov VG, Bennett SE, Beckman JS, Barofsky DF. ECD of tyrosine phosphorylation in a triple quadrupole mass spectrometer with a radio-frequency-free electromagnetostatic cell. J Am Soc Mass Spectrom. 2014 Oct;25(10):1730-8. PMC4163116. Shows efficient sequences of doubly charged phosphotyrosine-containing peptides compared to CID and ECD in FT-ICR instruments. The thermal radiation from the hot filament helps dissociate "sticky" fragments after fragmentation to produce clean spectra.
3. Voinov VG, Deinzer ML, Beckman JS, Barofsky DF. Electron capture, collision-induced, and electron capture-collision induced dissociation in Q-TOF. J Am Soc Mass Spectrom. 2011 Apr;22(4):607-11.PMCID: PMC4285558.
4. Voinov VG, Beckman JS, Deinzer ML, Barofsky DF. Electron-capture dissociation (ECD), collision-induced dissociation (CID) and ECD/CID in a linear radio-frequency-free magnetic cell. Rapid Commun Mass Spectrom. 2009 Sep;23(18):3028-30. doi: 10.1002/rcm.4209. PubMed PMID: 19685479; PubMed Central PMCID: PMC3057201.
5. Voinov VG, Deinzer ML, Barofsky DF. Radio-frequency-free cell for electron capture dissociation in tandem mass spectrometry. Anal Chem. 2009 Feb 1;81(3):1238-43. PMCID: PMC3066179.
6. Voinov VG, Deinzer ML, Barofsky DF. Electron capture dissociation in a linear radiofrequency-free magnetic cell. Rapid Commun Mass Spectrom. 2008 Oct;22(19):3087-8. PMCID: PMC3045275.
7. Voinov VG, Vasil'ev YV, Ji H, Figard B, Morré J, Egan TF, Barofsky DF, Deinzer ML. A gas chromatograph/resonant electron capture-TOF mass spectrometer for four dimensions of negative ion analytical information. Anal Chem. 2004 May 15;76(10):2951-7. PMID: 15144209.