Fast capillary electrochromatographic analysis of parabens and 4-hydroxybenzoic acid in drugs and cosmetics.

摘要: A fast capillary electrochromatographic method was developed for the analysis of paraben preservatives in drugs and cosmetics presence their main metabolite and/or impurity, 4-hydroxybenzoic acid. The separation optimized a 75 num ID capillary, fully packed with 5 C18 stationary phase, studying effects mobile phase pH composition (buffer type organic solvent content). mM ammonium formate, 3.0, containing 65% acetonitrile allowed us to obtain baseline methyl-, ethyl-, propyl-, butyl-, benzylparabens from mixture less than 2.5 min repeatability linearity using short-end injection (8 cm effective length). Under optimum experimental conditions, provided high efficiency parabens, range 129 312-140 325 number theoretical plates per meter, analyte quantitation limits (LOQs) 1.25-2.50 nug/mL. successfully applied quantitative pharmaceutical cosmetic industrial samples direct or after reduced sample pretreatment.