title: Determination by gas chromatography/mass spectrometry of p-phenylenediamine in hair dyes after conversion to an imine derivative.
abstract: In this paper we describe an analytical method for the determination of p-phenylenediamine (PPDA) in hair dyes. In the adopted methodology the analyte is transformed into the corresponding imine derivative by treatment with benzaldehyde, and then analyzed by gas chromatography (GC) combined to mass spectrometry (MS), operating in SIM conditions. The direct and simultaneous chemical derivatization of the two amino functions of the analyte with benzaldehyde enhances the instrumental responses enabling the use of a sensitive and accurate method. Concentrations of PPDA in a set of commercial hair coloring creams are determined making use of N-benzylidene-4-methylbenzene-amine as a very stable internal standard which is easily prepared by condensation of 4-methylbenzene-amine with benzaldehyde. The regression calibration curves for PPDA in hair dyes are linear within 0.1 +/- 25 mg/ml with 0.99 as a typical correlation coefficient.
authors.affiliation: Dipartimento di Scienze Farmnnaceutiche, Università degli Studi della Calabria, Via P Bucci, Cubo 15/C, 1-87036 Arcavacata di Rende (CS), Italy.
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Di Gioia
authors.forename: Antonella
authors.initials: A
authors.lastname: Leggio
authors.forename: Adolfo
authors.initials: A
authors.lastname: Le Pera
authors.forename: Angelo
authors.initials: A
authors.lastname: Liguori
authors.forename: Anna
authors.initials: A
authors.lastname: Napoli
authors.forename: Francesca
authors.initials: F
authors.lastname: Perri
authors.forename: Carlo
authors.initials: C
authors.lastname: Siciliano
mesh_terms: D000089:Acetic Anhydrides; D001547:Benzaldehydes / Q000737:chemistry; D005463:Fluoroacetates; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006202:Hair Dyes / Q000737:chemistry*; D007097:Imines / Q000032:analysis* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010655:Phenylenediamines / Q000032:analysis* / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D000089:Acetic Anhydrides; D001547:Benzaldehydes; D005463:Fluoroacetates; D006202:Hair Dyes; D007097:Imines; D010655:Phenylenediamines; C017958:trifluoroacetic anhydride; D014269:Trifluoroacetic Acid; C032175:benzaldehyde; C029728:4-phenylenediamine