Extraction and determination of polybrominated diphenyl ethers in water and urine samples using solidified floating organic drop microextraction along with high performance liquid chromatography

We have developed a method, termed solidification of floating organic drop microextraction (SFOME), for the extraction of polybrominated diphenyl ethers (PBDEs) in water and urine samples, this followed by quantification via HPLC. This method requires very small quantities of organic solvent consumption. It is based on exposing a floating solidified drop of an organic solvent on the surface of aqueous solution in a sealed vial. The organic drop is easily collected with a spatula, molten (at ambient temperature), and then submitted to HPLC. Experimental parameters including extraction solvent and its volume, disperser solvent and its volume, extraction time, ionic strength, stirring speed and extraction temperature were optimized. The enrichment factors of analytes are in the range from 921 to 1,462, and acceptable extraction recoveries (92%-118%) are obtained. The dynamic linear range for five PBDE congeners is in the range of 0.5-75 mu g.L-1 and from 5 to 500 mu g.L-1 for BDE 209. The correlation coefficients range from 0.9960 to 0.9999. The limits of detection (at S/N = 3) for PBDE congeners vary between 0.01 and 0.04 mu g.L-1. This method has been successfully applied to detecting PBDEs in two environmental waters and in human urine.