title: Multiwalled carbon nanotubes coated fibers for solid-phase microextraction of polybrominated diphenyl ethers in water and milk samples before gas chromatography with electron-capture detection.
abstract: Determination of polybrominated diphenyl ethers (PBDEs) in environmental samples has raised great concerns due to the widespread use of PBDEs and their potential risk to humans. Solid-phase microextraction (SPME) is a fast, simple, cost-effective, and green sample preparation technique and is widely used for environmental analysis, but reports on the application of SPME for determination of PBDEs are very limited, and only a few publications dealing with commercial SPME fibers are available for extraction of PBDEs. Herein, we report a novel SPME method using multiwalled carbon nanotubes (MWCNTs) as the SPME fiber coating for gas chromatography with electron-capture detection (GC-ECD) of PBDEs in environmental samples. The MWCNTs coating gave much higher enhancement factors (616-1756) than poly (5% dibenzene-95% dimethylsiloxane) coating (139-384) and activated carbon coating (193-423). Thirty-minute extraction of 10 mL of sample solution using the MWCNTs coated fiber for GC-ECD determination yielded the limits of detection of 3.6-8.6 ng L(-1) and exhibited good linearity of the calibration functions (r(2)>0.995). The precision (RSD%, n=4) for peak area and retention time at the 500 ng L(-1) level was 6.9-8.8% and 0.6-0.9%, respectively. The developed method was successfully applied for the analysis of real samples including local river water, wastewater, and milk samples. The recovery of the PBDEs at 500 ng L(-1) spiked in these samples ranged from 90 to 119%. No PBDEs were detected in the river water and skimmed milk samples, whereas in the wastewater sample, 134-215 ng L(-1) of PBDEs were found. The PBDEs were detected in all whole fat milk samples, ranging from 13 to 484 ng L(-1). In a semiskimmed milk sample, only BDE-47 was found at 21 ng L(-1).
authors.affiliation: Key Laboratory of Functional Polymer Materials, Ministry of Education, Research Center for Analytical Sciences, College of Chemistry, Nankai University, Tianjin 300071, China.
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Wang
authors.forename: Dong-Qing
authors.initials: DQ
authors.lastname: Jiang
authors.forename: Zhi-Yuan
authors.initials: ZY
authors.lastname: Gu
authors.forename: Xiu-Ping
authors.initials: XP
authors.lastname: Yan
mesh_terms: D000818:Animals; D002417:Cattle; D002849:Chromatography, Gas / Q000379:methods*; D005506:Food Contamination / Q000032:analysis; D006842:Hydrocarbons, Brominated / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D037742:Nanotubes, Carbon; D010647:Phenyl Ethers / Q000032:analysis*; D052617:Solid Phase Microextraction / Q000295:instrumentation* / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D006842:Hydrocarbons, Brominated; D037742:Nanotubes, Carbon; D010647:Phenyl Ethers; D014874:Water Pollutants, Chemical