Fundamental Studies on Poly(2-oxazoline) Side Chain Isomers Using Tandem Mass Spectrometry and Ion Mobility-Mass Spectrometry

  • Jean R. N. HalerEmail author
  • Victor R. de la Rosa
  • Philippe Massonnet
  • Johann Far
  • Richard Hoogenboom
  • Edwin De Pauw
Research Article


When polymer mixtures become increasingly complex, the conventional analysis techniques become insufficient for complete characterization. Mass spectrometric techniques can satisfy this increasing demand for detailed sample characterization. Even though isobaric polymers are indistinguishable using simple mass spectrometry (MS) analyses, more advanced techniques such as tandem MS (MS/MS) or ion mobility (IM) can be used. Here, we report proof of concept for characterizing isomeric polymers, namely poly(2-n-propyl-2-oxazoline) (Pn-PrOx) and poly(2-isopropyl-2-oxazoline) (Pi-PrOx), using MS/MS and IM-MS. Pi-PrOx ions lose in intensity at higher accelerating voltages than Pn-PrOx ions during collision-induced dissociation (CID) MS/MS experiments. A Pn/i-PrOx mixture could also be titrated using survival yield calculations of either precursor ions or cation ejection species. IM-MS yielded shape differences in the degree of polymerization (DP) regions showing the structural rearrangements. Combined MS techniques are thus able to identify and deconvolute the molar mass distributions of the two isomers in a mixture. Finally, the MS/MS and IM-MS behaviors are compared for interpretation.

Graphical Abstract



Poly(2-oxazoline)s Synthetic polymer isomers Tandem mass spectrometry MS/MS Collision-induced dissociation Ion mobility-mass spectrometry 



The authors acknowledge the financial support of the F.R.S.-FNRS (FRIA). R. Hoogenboom acknowledges financial support from FWO and Ghent University.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that there are no competing interests.

Supplementary material

13361_2019_2173_MOESM1_ESM.pdf (2.5 mb)
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Copyright information

© American Society for Mass Spectrometry 2019

Authors and Affiliations

  1. 1.Mass Spectrometry Laboratory, MolSys Research unit, Quartier AgoraUniversity of LiègeLiègeBelgium
  2. 2.Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular ChemistryGhent UniversityGhentBelgium

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