title: Analysis and differentiation of paper samples by capillary electrophoresis and multivariate analysis.
abstract: This work reports an investigation for the analysis of different paper samples using CE with laser-induced detection. Papers from four different manufactures (white-copy paper) and four different paper sources (white and recycled-copy papers, adhesive yellow paper notes and restaurant serviettes) were pulverized by scratching with a surgical scalpel prior to their derivatization with a fluorescent labeling agent, 8-aminopyrene-1,3,6-trisulfonic acid. Methodological conditions were evaluated, specifically the derivatization conditions with the aim to achieve the best S/N signals and the separation conditions in order to obtain optimum values of sensitivity and reproducibility. The best conditions, in terms of fastest, and easiest sample preparation procedure, minimal sample consumption, as well as the use of the simplest and fastest CE-procedure for obtaining the best analytical parameters, were applied to the analysis of the different paper samples. The registered electropherograms were pretreated (normalized and aligned) and subjected to multivariate analysis (principal component analysis). A successful discrimination among paper samples without entanglements was achieved. To the best of our knowledge, this work presents the first approach to achieve a successful differentiation among visually similar white-copy paper samples produced by different manufactures and paper from different paper sources through their direct analysis by CE-LIF and subsequent comparative study of the complete cellulose electropherogram by chemometric tools.
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Multipurpose Building of Chemistry, University of Alcalá, Alcalá de Henares, Spain; University Institute of Research in Police Sciences (IUICP), University of Alcalá, Alcalá de Henares, Spain.
authors: Ma Ángeles
authors: MÁ
authors: Fernández de la Ossa
authors: Fernando
authors: F
authors: Ortega-Ojeda
authors: Carmen
authors: C
authors: García-Ruiz
mesh_terms: D002482:Cellulose / Q000032:analysis* / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry; D057230:Limit of Detection; D015999:Multivariate Analysis; D010209:Paper; D025341:Principal Component Analysis
chemical_list: D005456:Fluorescent Dyes; D002482:Cellulose
keywords: Capillary electrophoresis; Cellulosic samples; Fluorescent labeling; Forensic Analysis; Principal component analysis