title: Efficient flow injection and sequential injection methods for spectrophotometric determination of oxybenzone in sunscreens based on reaction with Ni(II).
abstract: Spectrophotometric determination of a widely used UV-filter, such as oxybenzone, is proposed. The method is based on the complexation reaction between oxybenzone and Ni(II) in ammoniacal medium. The stoichiometry of the reaction, established by the Job method, was 1:1. Reaction conditions were studied and the experimental parameters were optimized, for both flow injection (FI) and sequential injection (SI) determinations, with comparative purposes. Sunscreen formulations containing oxybenzone were analyzed by the proposed methods and results compared with those obtained by HPLC. Data show that both FI and SI procedures provide accurate and precise results. The ruggedness, sensitivity and LOD are adequate to the analysis requirements. The sample frequency obtained by FI is three-fold higher than that of SI analysis. SI is less reagent-consuming than FI.
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universitat de València, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Chisvert
authors.forename: A
authors.initials: A
authors.lastname: Salvador
authors.forename: M C
authors.initials: MC
authors.lastname: Pascual-Martí
authors.forename: J G
authors.initials: JG
authors.lastname: March
mesh_terms: D000641:Ammonia; D001577:Benzophenones / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D007202:Indicators and Reagents; D009532:Nickel; D012680:Sensitivity and Specificity; D013053:Spectrophotometry / Q000295:instrumentation / Q000379:methods; D013473:Sunscreening Agents / Q000032:analysis* / Q000737:chemistry
chemical_list: D001577:Benzophenones; D007202:Indicators and Reagents; D013473:Sunscreening Agents; D000641:Ammonia; D009532:Nickel; C005290:oxybenzone