Determination of phthalates in beverages using multiwalled carbon nanotubes dispersive solid-phase extraction before HPLC-MS

作者：Gonzalez Salamo Javier; Hernandez Borges Javier^*; del Mar Afonso Maria; Angel Rodriguez Delgado Miguel

来源：Journal of Separation Science, 2018, 41(12): 2613-2622.

DOI：10.1002/jssc.201800192

• high-performance liquid chromatography
• mass spectrometry
• multiwalled carbon nanotubes
• phthalic acid esters
• plastic bottled drinks

A microdispersive solid-phase extraction method has been developed using multiwalled carbon nanotubes of 110-170 nm diameter and 5-9 pm length for the extraction of a group of nine phthalic acid esters (i.e., bis(2-methoxyethyl) phthalate, bis-2-ethoxyethyl phthalate, dipropyl phthalate, butylbenzyl phthalate, bis-2-n-butoxyethyl phthalate, bis-isopentyl phthalate, bis-n-pentyl phthalate, dicyclohexyl phthalate, and di-n-octyl phthalate) from tap water as well as from different beverages commercialized in plastic bottles (mineral water, lemon- and apple-flavored mineral water, and an isotonic drink). Determination was carried out by high-performance liquid chromatography coupled to mass spectrometry. The extraction procedure was optimized following a step-by-step approach, being the optimum extraction conditions: 50 mL of each sample at pH 6.0,80 mg of sorbent, and 25 mL of acetonitrile as elution solvent. To validate the methodology, matrix-matched calibration and a recovery study were developed, obtaining determination coefficients >0.9906 and absolute recovery values between 70 and 117% (with relative standard deviations < 17%) in all cases. The limits of quantification of the method were between 0.173 and 1.45 mu g/L. After the evaluation of the matrix effects, real samples were also analyzed, finding butylbenzyl phthalate in all samples (except in apple-flavored mineral water), though at concentrations below its limit of quantification of the method.

• 出版日期2018-6