title: Determination of endocrine-disrupting phenols in water samples by a new manual shaking-enhanced, ultrasound-assisted emulsification microextraction method.
abstract: Manual shaking-enhanced, ultrasound-assisted emulsification microextraction (MS-USAEME) combined with ultraperformance liquid chromatography (UPLC) with UV detection has been developed for the determination of five endocrine-disrupting phenols (EDPs) in seawater samples and detergent samples: 4-tert-butylphenol (4-t-BP), 4-cumylphenol (4-CP), 4-tert-octylphenol (4-t-OP), 2,4-di-tert-butylphenol (2,4-di-t-BP) and 4-nonylphenol (4-NP). Optimum conditions were found to be: 25 μL 1-bromohexadecane as extraction solvent, 5 mL of aqueous sample and 1 g of NaCl to control the ionic strength; manual shaking for 10 s; ultrasonication for 1 min; centrifugation for 3 min at 5000 rpm (speed). For MS-USAEME, manual shaking for 10 s is essential for effective extraction when the ultrasonic extraction time is as brief as 1 min. The small volume of aqueous sample enhances the effect of manual shaking significantly. For seawater samples, the limit of detection (LOD) was 0.5-2.8 ng mL(-1), the limit of quantification (LOQ) was 1.8-9.3 ng mL(-1) with the relative standard deviation (RSD) in the range 4.2-10.3%. For detergent samples, the LOD was 0.4-2.4 ng mL(-1), LOQ was 1.6-8.2 ng mL(-1) and RSD 4.7-10.0%. The relative recovery was 96-109% for seawater samples and 81-106% for the detergent samples.
authors.affiliation: Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Ming-Wei
authors.initials: MW
authors.lastname: Shu
authors.forename: Mei-I
authors.initials: MI
authors.lastname: Leong
authors.forename: Ming-Ren
authors.initials: MR
authors.lastname: Fuh
authors.forename: Shang-Da
authors.initials: SD
authors.lastname: Huang
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D004655:Emulsions; D052244:Endocrine Disruptors / Q000032:analysis* / Q000302:isolation & purification*; D005898:Glass / Q000737:chemistry; D009994:Osmolar Concentration; D010636:Phenols / Q000032:analysis* / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D013010:Sonication / Q000379:methods*; D013997:Time Factors; D014867:Water / Q000737:chemistry*
chemical_list: D004655:Emulsions; D052244:Endocrine Disruptors; D010636:Phenols; D012997:Solvents; D014867:Water