| Migration of chemicals from plastic containers into drinks and liquids is supposed to be a hazardous phenomenon resulting in many
health problems. Sample preparation is of great importance due to trace amounts analysis of these compounds. In this research, dispersive
liquid-liquid microextraction is applied for the extraction and preconcentration of the migrated compounds prior to their detection and
determination by gas chromatography equipped with mass spectrometry or flame ionization detector. The method is based on forming
droplets of a water-immiscible organic solvent (extractant) into an aqueous phase using a disperser solvent. As a result, there would be a
large contact area between the extractant and aqueous phase containing the analytes which boosts mass transfer. After centrifuging, the
extractant is sedimented at the bottom of the aqueous phase and an aliquot of it is removed and injected into the separation system. Various
experimental conditions influencing the extraction efficiency were optimized. Under the optimum conditions, the extraction recoveries
were ranged from 52-63%. Also, the enrichment factors for the target compounds were calculated to be in the range of 2600-3150. The
linear ranges were achieved in the range of 0.61-1000 µg l-1. The relative standard deviations were ≤ 7.2% for intra- (n = 6) and inter-day
(n = 4) precisions at a concentration of 20 µg l-1 of each analyte. The limits of detection were in the range of 0.18-0.38 µg l-1. Eventually,
the applicability of the proposed method for appraising the migrated compounds from plastic containers including butylated hydroxy
anisole, butylated hydroxy toluene, bisphenol A, dibutyl phthalate, diethyl phthalate, di-isobutyl phthalate, and p-xylene was evaluated by
analyzing them in different drinks and liquids stored in the plastic bottles. |