title: Simultaneous determination of seven phthalic acid esters in beverages using ultrasound and vortex-assisted dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.
abstract: A sensitive, rapid, and simple high-performance liquid chromatography with UV detection method was developed for the simultaneous determination of seven phthalic acid esters (dimethyl phthalate, dipropyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, dicyclohexyl phthalate, di-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in several kinds of beverage samples. Ultrasound and vortex-assisted dispersive liquid-liquid microextraction method was used. The separation was performed using an Intersil ODS-3 column (C18 , 250 × 4.6 mm, 5.0 μm) and a gradient elution with a mobile phase consisting of MeOH/ACN (50:50) and 0.2 M KH2 PO4 buffer. Analytes were detected by a UV detector at 230 nm. The developed method was validated in terms of linearity, limit of detection, limit of quantification, repeatability, accuracy, and recovery. Calibration equations and correlation coefficients (> 0.99) were calculated by least squares method with weighting factor. The limit of detection and quantification were in the range of 0.019-0.208 and 0.072-0.483 μg/L. The repeatability and intermediate precision were determined in terms of relative standard deviation to be within 0.03-3.93 and 0.02-4.74%, respectively. The accuracy was found to be in the range of -14.55 to 15.57% in terms of relative error. Seventeen different beverage samples in plastic bottles were successfully analyzed, and ten of them were found to be contaminated by different phthalic acid esters.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Istanbul University, Istanbul, Turkey.
authors.forename: Pelin Köseoğlu
authors.initials: PK
authors.lastname: Yılmaz
authors.forename: Abdulselam
authors.initials: A
authors.lastname: Ertaş
authors.forename: Ufuk
authors.initials: U
authors.lastname: Kolak
mesh_terms: D001628:Beverages / Q000032:analysis*; D002138:Calibration; D002253:Carbonated Beverages / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D061215:Energy Drinks / Q000032:analysis; D004952:Esters / Q000032:analysis*; D005504:Food Analysis / Q000379:methods; D005638:Fruit; D059627:Liquid Phase Microextraction; D000432:Methanol / Q000737:chemistry; D010795:Phthalic Acids / Q000032:analysis*; D015203:Reproducibility of Results; D014465:Ultrasonics; D014675:Vegetables
chemical_list: D004952:Esters; D010795:Phthalic Acids; D000432:Methanol
keywords: Beverages; High-performance liquid chromatography; Liquid-liquid microextraction; Phthalic acid esters