Desorption electrospray ionization ‐ orbitrap mass spectrometry of synthetic polymers and copolymers

Desorption ElectroSpray Ionization (DESI) ‐ Orbitrap Mass Spectrometry (MS) was evaluated as a new tool for the characterization of various industrial synthetic polymers (poly(ethylene glycol), poly(propylene glycol), poly(methylmethacrylate), poly(dimethylsiloxane)) and copolymers, with masses ranging from 500 g.mol −1 up to more than 20 000 g.mol −1 . Satisfying results in terms of signal stability and sensitivity were obtained from hydrophobic surfaces (HTC Prosolia) with a mixture water/methanol (10/90) as spray solvent in the presence of sodium salt. Taking into account the formation of multiplied charged species by DESI‐MS, a strategy based on the use of a deconvolution software followed by the automatic assignment of the ions was described allowing the rapid determination of M n , M w and PDI values. DESI‐Orbitrap MS results were compared to those obtained from matrix‐assisted laser desorption/ionization‐ time‐of‐flight MS and gel permeation chromatography. An application of DESI‐Orbitrap MS for the detection and identification of polymers directly from cosmetics was described. Copyright © 2012 John Wiley & Sons, Ltd.