On-line Abstract Book

The Use of Pulsed Gradient Spin Echo Nuclear Magnetic Resonance as a Tool in MALDI Method Development for Polymer Molecular Weight Determination

Michael Mazarin¹, Stephane Viel¹, Beatrice Allard-Breton², Andre Thevand¹, Laurence Charles¹

Correspondence address: Michael Mazarin, University Aix-Marseille I, JE2421 TRACES, Av Escadrille Normandie-Niemen, Marseille, 13397 Cedex 20 France.

Keywords: Ionization, Matrix-Assisted Laser Desorption; Molecular Weight Determination; Molecular Weight Distribution; Polymer.

Novel aspect: Combination of mass spectrometry and nuclear magnetic resonance for polymer characterization.

 

Mass Spectrometry (MS) and Pulsed Gradient Spin Echo (PGSE) Nuclear Magnetic Resonance (NMR) have been advantageously combined to achieve more reliable molecular weight information for polymers. Specifically, PGSE was shown to be a convenient tool for a rapid evaluation of Mw values to be further used as guidelines in Matrix-Assisted Laser Desorption/Ionization (MALDI) sample preparation. PGSE calibration curves, established under given experimental conditions, are particularly robust, as they could be applied satisfactorily on different commonly available NMR instruments and different time frames. PGSE results were shown to compare well with size exclusion chromatography data used as a reference to validate this alternative technique. Moreover, because PGSE is relatively fast, it can be used interactively with MALDI analysis to check and understand mass spectrum profiles. This approach was first tested on poly(methylmethacrylate) (PMMA) standards and then successfully applied to determine the molecular weight of two unknown samples, a PMMA and a poly(ethylene glycol) monomethacrylate (PEGMMA) polymer.