Professor Doug Barofsky will be visiting the Centre on Friday 26th of February and will be giving a lecture on 'An Electromagnetostatic Technology for MS/MS Dissociation Cells and General Transmission Components in Mass Spectrometers' at 2.00 pm in room F1.07.

An Electromagnetostatic Technology for MS/MS Dissociation Cells and
General Transmission Components in Mass Spectrometers

Douglas F. Barofsky,Department of Chemistry, Oregon State University, Corvallis, Oregon 97331

A radio frequency-free (RFF), analyzer-independent cell has been devised for electron-capture dissociation (ECD) of ions.  The device is based on interleaving a series of electrostatic lenses with the periodic structure of magnetostatic lenses commonly found in a traveling wave tube.  A five-magnet version of the RFF electromagnetostatic ECD cell was installed in a Finnigan TSQ700 ESI triple quadrupole (QqQ) spectrometer, and its performance was evaluated by recording product-ion spectra of various peptides.  These spectra were readily obtained without recourse to a buffering gas or synchronizing electron injection with a specific phase of an RF field.  The mass spectra produced with the modified instrument appear in all respects (other than resolution and mass accuracy, which were limited by the mass spectrometer used) to be at least as good for purposes of peptide identification as those recorded with Fourier transform ion cyclotron resonance (FT ICR) instruments; however, the effort and time to produce the mass spectra were much less than required to produce their FT ICR counterparts.  A two-magnet version of the electromagnetostatic ECD cell was installed in the same mass spectrometer and used to simultaneously obtain combined ECD/CID product-ion mass spectra that exhibit a-, b-, and c-type ion signals.  Details of the cells design, construction, and operation plus possibilities for using the electromagnetostatic technology in the larger context of ion transmission and trapping will be presented and discussed.