title: Evaluation of matrix-assisted laser desorption/ionization mass spectrometry for second-generation lignin analysis.
abstract: Matrix-Assisted Laser Desorption/Ionization time-of-flight (MALDI-TOF) mass spectrometry is evaluated as an elucidation tool for structural features and molecular weights estimation of some extracted herbaceous lignins. Optimization of analysis conditions, using a typical organic matrix, namely α-cyano-4-hydroxycinnamic acid (CHCA), in combination with α-cyclodextrin, allows efficient ionization of poorly soluble lignin materials and suppression of matrix-related ions background. Analysis of low-mass fragments ions (m/z 100-600) in the positive ion mode offers a "fingerprint" of starting lignins that could be a fine strategy to qualitatively identify principal inter-unit linkages between phenylpropanoid units. The molecular weights of lignins are estimated using size exclusion chromatography and compared to MALDI-TOF-MS profiles. Miscanthus (Miscanthus x giganteus) and Switchgrass (Panicum Virgatum L.) lignins, recovered after a formic acid/acetic acid/water process or aqueous ammonia soaking, are selected as benchmarks for this study.
authors.affiliation: Unit of Biological and Industrial Chemistry, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium.
authors.forename: Aurore
authors.initials: A
authors.lastname: Richel
authors.forename: Caroline
authors.initials: C
authors.lastname: Vanderghem
authors.forename: Mathilde
authors.initials: M
authors.lastname: Simon
authors.forename: Bernard
authors.initials: B
authors.lastname: Wathelet
authors.forename: Michel
authors.initials: M
authors.lastname: Paquot
keywords: biomass; lignin; mass spectrometry