Determination of 17 phthalate esters in water using GC–MS combined with magnetic solid phase extraction with Fe3O4@GO

Abstract

In this study, a new technique was developed which combines magnetic solid phase extraction (MSPE) and gas chromatography-mass spectrometer (GC–MS), for the analysis of 17 phthalate esters (PAEs). First, a composite of iron (used as the magnetic part) and graphene oxide (GO) was synthesized for application in MSPE. Scanning electron microscop, X-ray diffraction and infrared spectroscopy were used to characterize this material. Finally, magnetic graphene oxide (Fe₃O₄@GO) was used to extract PAEs from water samples. Various parameters relevant to the extraction were optimized, such as the amount of adsorbent employed, adsorption time, luent solvent types and volume, and sample pH. These optimum conditions resulted in calibration curves for the 17 PAEs, showing linear relationships between concentration and response at concentrations of 25 to 2500 µg L⁻¹ with correlation coefficients from 0.9983 to 1.000. Limit of detection and limit of quantitationfor the PAEs ranged from 0.030 to 0.12 µg L⁻¹ and 0.10–0.40 µg L⁻¹, respectively. The recovery rates for these compounds in spiked samples were ranging from 81.5% to 109% with relative standard deviation less than 6.12%. The effectiveness of method was further demonstrated by its use in detecting 17 PAEs in samples of drinking and bottled water. Compounds such as DEP, DIBP, DBP, and DCHP were identified. These results thus highlight the suitability of Fe₃O₄@GO as an adsorbent for concentrating and purifying PAEs in water samples.