title: Vortex-assisted emulsification semimicroextraction for the analytical control of restricted ingredients in cosmetic products: determination of bronopol by liquid chromatography.
abstract: Vortex-assisted emulsification semimicroextraction is proposed as a one-step solution-extraction procedure for sample preparation in cosmetic products. The procedure allows rapid preparation based on dispersion of the sample in a mixture of 1 mL of n-hexane and 0.5 mL of ethanol, followed by the addition of 0.5 mL of water and centrifugation to obtain two separated phases. This procedure provides good sample clean-up with minimum dilution and is very useful for the determination of ingredients with restricted concentrations, such as bronopol. The procedure was applied to the determination of bronopol by liquid chromatography with UV detection. The best chromatographic separation was obtained by using a C18 column set at 40 °C and performing a stepwise elution with a mixture of ethanol/aqueous 1 % acetic acid solution as mobile phase pumped at 0.5 mL min(-1). The detection wavelength was set at 250 nm and the total run time required was 12 min. The method was successfully applied to 18 commercial cosmetic samples including creams, shampoos, and bath gels. Good recoveries and repeatability were obtained, with a limit of detection of 0.9 μg mL(-1), which makes the method suitable for the analytical control of cosmetic products. Moreover, it could be considered environmentally friendly, because water, ethanol, and only a low volume of n-hexane are used as solvents.
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universitat de València, 46100, Burjassot, Valencia, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Miralles
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universitat de València, 46100, Burjassot, Valencia, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Bellver
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universitat de València, 46100, Burjassot, Valencia, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Chisvert
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universitat de València, 46100, Burjassot, Valencia, Spain. amparo.salvador@uv.es.
authors.forename: Amparo
authors.initials: A
authors.lastname: Salvador
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D003358:Cosmetics / Q000032:analysis*; D004655:Emulsions / Q000737:chemistry*; D006586:Hexanes / Q000737:chemistry; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000379:methods*; D011310:Preservatives, Pharmaceutical / Q000032:analysis* / Q000302:isolation & purification; D011409:Propylene Glycols / Q000032:analysis* / Q000302:isolation & purification; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D003358:Cosmetics; D004655:Emulsions; D006586:Hexanes; D011310:Preservatives, Pharmaceutical; D011409:Propylene Glycols; D012997:Solvents; D014867:Water; C026385:n-hexane; C006827:bronopol
keywords: Bronopol; Cosmetic products; Liquid chromatography; Semimicroextraction; Vortex-assisted emulsification