title: New chemometric approach MCR-ALS to unmix EPR spectroscopic data from complex mixtures.
abstract: Electron paramagnetic resonance (EPR) spectra of mixtures are often difficult to interpret due to the superposition of spectral contribution of various species present in the complex materials. It is challenging to accurately identify the number of pure compounds present and to extract their pure spectra. In this study, the powerful chemometric method, multivariate curve resolution-alternating least squares (MCR-ALS), is applied to identify different paramagnetic centers. This method is used to simultaneously extract, with no prior knowledge, the pure spectra and the corresponding concentration profiles of all the compounds in the unknown and unresolved mixtures. The goal of our work is to apply, for the first time, this new chemometrics methodology, MCR-ALS, on EPR spectroscopic data in order to characterize a series of distinct but strongly overlapping spectra of various paramagnetic species.
authors.affiliation: LASIR CNRS UMR 8516, Université Lille 1, Sciences et Technologies, 59655 Villeneuve d'Ascq Cedex, France.
authors.forename: Maya
authors.initials: M
authors.lastname: Abou Fadel
authors.affiliation: Grup de Quimiometria, Quimica Analitica, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: de Juan
authors.affiliation: LASIR CNRS UMR 8516, Université Lille 1, Sciences et Technologies, 59655 Villeneuve d'Ascq Cedex, France.
authors.forename: Nadia
authors.initials: N
authors.lastname: Touati
authors.affiliation: LASIR CNRS UMR 8516, Université Lille 1, Sciences et Technologies, 59655 Villeneuve d'Ascq Cedex, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Vezin
authors.affiliation: LASIR CNRS UMR 8516, Université Lille 1, Sciences et Technologies, 59655 Villeneuve d'Ascq Cedex, France. Electronic address: ludovic.duponchel@univ-lille1.fr.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Duponchel
mesh_terms: D000465:Algorithms; D016477:Artifacts; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D045424:Complex Mixtures / Q000032:analysis* / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D045424:Complex Mixtures
keywords: Chemometrics; Electron paramagnetic resonance spectroscopy; Multivariate curve resolution-alternating least squares; Paramagnetic centers