Determination of decabromodiphenyl ether in water samples by single-drop microextraction and RP-HPLC

This paper describes the development of a new method using single-drop microextraction (SDME) and RP-HPLC for the determination of decabromodiphenyl ether (BDE-209) in water samples. The effects of SDME parameters such as extraction solvent, microdrop volume, extraction time, stirring speed, salt concentration, and sample pH on the extraction performance are investigated. Under optimal extraction conditions (extraction solvent, toluene; solvent drop volume, 3.0 microL; extraction time, 15 min; stirring speed, 600 rpm; no addition of salt and change of sample pH), the calibration curve was drawn by plotting peak area against a series of BDE-209 concentrations (0.001-1 microg/mL) in aqueous solution; the correlation coefficient (r) was 0.9998. The limit of detection was 0.7 ng/mL. The enrichment factor was 10.6. The precision of this method was obtained by six successive analyses of a 100 ng/mL standard solution of BDE-209, and RSD was 4.8%. This method was successfully applied to the extraction of BDE-209 from tap and East Lake water samples with relative recoveries ranging from 92.5 to 102.8% and from 91.5 to 96.2%, respectively, and the relative standard deviations (n = 3) were 4.4 and 2.2%. The proposed method is acceptable for the analysis of BDE-209 in water samples.