title: Determination of bisphenol A in human breast milk by HPLC with column-switching and fluorescence detection.
abstract: A highly sensitive HPLC method was developed for the determination of xenoestrogenic compound, bisphenol A (BPA) in human breast milk samples. After a two-step liquid-liquid extraction, BPA was derivatized with fluorescent labeling reagent, 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl). The excess fluorescent reagent could be removed effectively using a column-switching system. The separation of DIB-BPA from endogenous materials in milk was carried out on two C(18) columns and fluorescence intensity was monitored at 475 nm with the excitation of 350 nm. A good linearity (r = 0.994) was observed of BPA in the concentration range of 0.2-5.0 ng mL(-1) in breast milk, and the detection limit was 0.11 ng mL(-1) at a signal-to-noise ratio of 3. Intra- and inter-day precision (RSD, %) were less than 8.7 and 10.4, respectively. Twenty-three breast milk samples of healthy lactating women were analyzed for the BPA concentration; the mean value was 0.61 +/- 0.20 ng mL(-1), with no correlation to the lipid content of milk samples.
authors.affiliation: Division of Analytical Research for Pharmacoinformatics, Department of Clinical Chemistry, Course of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Yen
authors.initials: Y
authors.lastname: Sun
authors.forename: Miki
authors.initials: M
authors.lastname: Irie
authors.forename: Naoya
authors.initials: N
authors.lastname: Kishikawa
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Wada
authors.forename: Naotaka
authors.initials: N
authors.lastname: Kuroda
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Nakashima
mesh_terms: D001559:Benzhydryl Compounds; D001565:Benzoates; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004968:Estrogens, Non-Steroidal / Q000032:analysis; D005456:Fluorescent Dyes; D006801:Humans; D007093:Imidazoles; D008895:Milk, Human / Q000737:chemistry*; D010636:Phenols / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D001565:Benzoates; D004968:Estrogens, Non-Steroidal; D005456:Fluorescent Dyes; D007093:Imidazoles; D010636:Phenols; C114684:4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride; C006780:bisphenol A; D000098826:Bisphenol A Compounds