Development of a dispersive liquid-liquid microextraction method for the determination of polychlorinated biphenyls in water.
A very simple and powerful microextraction procedure, the dispersive liquid-liquid microextraction (DLLME), was used for the determination of the content of 10 polychlorinated biphenyls (PCBs) in water samples, using gas chromatography coupled with electron-capture detection (GC-ECD). The appropriate amount of acetone (disperser solvent) and chlorobenzene (extraction solvent) at the microlevel volume was used for this procedure. The conditions for the microextraction performance were investigated and optimized. The optimized method exhibited a good linearity (R(2)>0.996) over the studied range (0.005-2 microg L(-1)), illustrating a satisfactory precision level with R.S.D. values between 4.1% and 11.0%. The values of the detection limit (S/N=3) were found to be lower than 0.002 microg L(-1). Furthermore, a large enrichment factor for the analytes (up to a 540-fold) was achieved in a very short time for only a 5.00-mL water sample. The effectiveness of the method towards real samples was tested by analyzing well, river and seawater samples. The relative recoveries of the well, river and seawater samples, which had been spiked with different levels of PCBs were equal to 92.0-114.0%, 97.0-102.0% and 96.0-103.0%, respectively. The attained results demonstrated that DLLME combined with GC-ECD was a fast and inexpensive technique for the PCBs determination in water samples.
Rezaei
Fatemeh
F
Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran, Iran.
Bidari
Araz
A
Birjandi
Afsoon Pajand
AP
Milani Hosseini
Mohammad Reza
MR
Assadi
Yaghoub
Y
D011078:Polychlorinated Biphenyls / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis*
D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls