title: Analysis and characterization of aluminum chlorohydrate oligocations by capillary electrophoresis.
abstract: Aluminum chlorohydrates (ACH) are the active ingredients used in most antiperspirant products. ACH is a water soluble aluminum complex which contains several oligomeric polycations of aluminum with degrees of polymerization up to Al13or Al30. The characterization and quantification of ACH oligo-cations remain a challenging issue of primary interest for developing structure/antiperspirant activity correlations, and for controlling the ACH ingredients. In this work, highly repeatable capillary electrophoresis (CE) separation of Al3+, Al13and Al30oligomers contained in ACH samples was obtained at pH 4.8, owing to a careful choice of the background electrolyte counter-ion and chromophore, capillary I.D. and capillary coating. This is the first reported separation of Al13and Al30oligomers in conditions that are compatible with the aluminum speciation in ACH solution or in conditions of antiperspirant application/formulation. Al13and Al30effective charge numbers were also determined from the sensitivity of detection in indirect UV detection mode. The relative mass proportion of Al13compared to Al13+Al30could be determined in different aluminum chlorohydrate samples. Due to its simplicity, repeatability/reproducibility, minimal sample preparation and mild analytical conditions, CE appears to be a promising analytical separation technique for the characterization of ACH materials and for the study of structure/antiperspirant activity correlations.
authors.affiliation: Institut des Biomolécules Max Mousseron (UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier), Place Eugène Bataillon, CC 1706, 34095, Montpellier Cedex 5, France.
authors.forename: Nesrine
authors.initials: N
authors.lastname: Ouadah
authors.affiliation: L'Oréal Research & Innovation, Campus Aulnay Chanteloup, Avenue Eugène Schueller, 93600, Aulnay-Sous-Bois, France.
authors.forename: Claudine
authors.initials: C
authors.lastname: Moire
authors.affiliation: L'Oréal Research & Innovation, Campus Aulnay Chanteloup, Avenue Eugène Schueller, 93600, Aulnay-Sous-Bois, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Kuntz
authors.affiliation: L'Oréal Research & Innovation, Campus Aulnay Chanteloup, Avenue Eugène Schueller, 93600, Aulnay-Sous-Bois, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Brothier
authors.affiliation: Institut des Biomolécules Max Mousseron (UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier), Place Eugène Bataillon, CC 1706, 34095, Montpellier Cedex 5, France. Electronic address: herve.cottet@umontpellier.fr.
authors.forename: Hervé
authors.initials: H
authors.lastname: Cottet
mesh_terms: D000536:Aluminum Hydroxide / Q000032:analysis* / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D019075:Electrophoresis, Capillary; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002412:Cations; D000536:Aluminum Hydroxide; C016976:aluminum chlorhydrate
keywords: Aluminium chlorohydrates; Antiperspirant ingredients; Capillary coatings; Counterions; Indirect UV detection; Oligocations