Fragmentation of Polymers Using QCID FTMS
From LabAutopedia
Fragmentation of polymers using quadrupole collision induced dissociation Fourier transform mass spectrometry
Saša M. Miladinović1, Cynthia J. Kaeser1,2, Charles L. Wilkins1
1) University of Arkansas, Fayetteville, AR; 2) University of the Cumberlands, Williamsburg, KY
In recent years, many fragmentation techniques have been developed for use with Fourier transform mass spectrometry (FTMS) in sequencing peptides and polymers. Tandem mass spectrometric techniques such as quadrupole collision-induced dissociation (QCID) was used to fragment multiply-charged, high mass polyacrylate and polyether oligomers produced using an external electrospray ionization (ESI) source. High resolution FTMS analysis of QCID produced fragments is available in new generation hybrid FTMS instrument (Bruker APEX Qe, Billerica, MA). Although, tandem QCID Time-of-flight (TOF) techniques of polyacrylate and polyether polymers were heavily explored, here we report first QCID-FTMS of such systems. High fragmentation efficiency of QCID and high mass resolution with high mass accuracy of FTMS revealed novel fragmentation pattern of selected polyacrylate oligomers. QCID-FTMS produced intense fragmentation of selected oligomer, corresponding to various combinations of losses of monomers, end groups, and side chains. This method also showed evidence of the re-combination of fragments in the gas phase, making this method unsuitable for the analysis of an unknown polymer samples. Some fragments showed higher mass and charge than the isolated precursor ion. The fragmentation of oligomers of varying size were studied using either Li, Na, or Cs as the cation. The oligomers with Cs showed lowest fragmentation efficiency than lithiated and sodiated ions which is consistent with reported QCID-TOF results. To the best of our knowledge, this is the first observation that fragmentation and recombination pattern of the same polymer sample depends on the mass of isolated oligomer.
