title: Fast capillary electrochromatographic analysis of parabens and 4-hydroxybenzoic acid in drugs and cosmetics.
abstract: A fast capillary electrochromatographic method was developed for the analysis of paraben preservatives in drugs and cosmetics in the presence of their main metabolite and/or impurity, 4-hydroxybenzoic acid. The separation was optimized in a 75 num ID capillary, fully packed with 5 num C18 stationary phase, studying the effects of mobile phase pH and composition (buffer type and organic solvent content). The mobile phase 5 mM ammonium formate, pH 3.0, containing 65% acetonitrile allowed us to obtain the baseline separation of methyl-, ethyl-, propyl-, butyl-, and benzylparabens from a mixture in less than 2.5 min with repeatability and linearity using the short-end injection method (8 cm separation capillary effective length). Under the optimum experimental conditions, the method provided high separation efficiency for parabens, in the range of 129 312-140 325 number of theoretical plates per meter, and analyte quantitation limits (LOQs) in the range of 1.25-2.50 nug/mL. The method was successfully applied to the quantitative analysis of paraben preservatives in pharmaceutical and cosmetic industrial samples with direct injection or after reduced sample pretreatment.
authors.affiliation: Institute of Chemical Methodology, National Council of Research, Rome Research Area, Monterotondo Scalo, Rome, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: De Rossi
authors.forename: Claudia
authors.initials: C
authors.lastname: Desiderio
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003358:Cosmetics / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D010226:Parabens / Q000032:analysis*; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry
chemical_list: D003358:Cosmetics; D010226:Parabens; D004364:Pharmaceutical Preparations; D012997:Solvents; C038193:4-hydroxybenzoic acid