Evaluation of the combination of a dispersive liquid-liquid microextraction method with micellar electrokinetic chromatography coupled to mass spectrometry for the determination of estrogenic compounds in milk and yogurt.
In this work, the suitability of a methodology based on dispersive liquid-liquid microextraction (DLLME) has been evaluated for the extraction of four endoestrogens (estriol, 17α-estradiol, 17β-estradiol, and estrone), an exoestrogen (17α-etynylestradiol), and a mycotoxin (zearalenone), together with some of their major metabolites (2-methoxyestradiol, α-zearalanol, β-zearalanol, α-zearalenol, and β-zearalenol) from different types of milk (whole and skimmed cow milk and semiskimmed goat milk) and whole natural yogurt. The methodology includes a previous protein precipitation with acidified ACN and a defatting step with n-hexane. Separation of the analytes, determination, and quantification were developed by MEKC coupled to ESI-MS using a BGE containing an aqueous solution of ammonium perfluorooctanoate as MS friendly surfactant. Calibration, precision, and accuracy studies of the described DLLME-MEKC-MS/MS method were evaluated obtaining a good linearity and LODs in the low micrograms per liter range.
Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de La Laguna (ULL), La Laguna, Tenerife, España; Institute of Chemical Methodologies, Italian National Research Council-CNR, Monterotondo, Rome, Italy.
Giovanni
G
D'Orazio
María
M
Asensio-Ramos
Javier
J
Hernández-Borges
Miguel Ángel
MÁ
Rodríguez-Delgado
Salvatore
S
Fanali
D000818:Animals; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D004967:Estrogens / Q000032:analysis*; D004970:Estrone / Q000032:analysis; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D015014:Yogurt / Q000032:analysis*; D015025:Zearalenone / Q000032:analysis; D015029:Zeranol / Q000031:analogs & derivatives / Q000032:analysis
D004967:Estrogens; C029659:zearalenol; D004970:Estrone; D015025:Zearalenone; D015029:Zeranol; C028226:taleranol
Estrogens; Mass spectrometry; Micellar electrokinetic chromatography; Milk; Yogurt