Novel clean-up technique based on dispersive solid-phase extraction for the determination of polybrominated diphenyl ethers in biological samples

FONTANA, ARIEL R.; DANTE MARTINEZ, LUIS; ALTAMIRANO, JORGELINA C.

Simposio; XXXI International Symposium on Halogenated Persistent Organic Pollutants; 2011

PBDEs are synthetic compounds used as flame retardant additives into the polymeric mass. As polymer additives, they are not chemically bound to the structure; therefore, PBDEs can leach into the environment and reach animals and humans through their food chain and dust [1,2]. Thus, there is an increasing interest in studying biota samples potentially exposed to this type of persistent organic pollutants. Sample preparation of biological tissues samples has been recognized as the main bottleneck of the analytical process when trace analytes determination is carried out [3]. The complexity of these samples requires efficient extraction, clean-up and preconcentration strategies prior to GC?MS/MS analysis [4]. Recently, Anastassiades et al. proposed a rapid and simple technique for cleaning-up different food and environmental sample extracts named dispersive solid-phase extraction (DSPE) [5]. It is based on the addition of the sorbent material into an extract aliquot, which is then separated from the extract bulk by centrifugation. In this way, DSPE avoids using SPE column and requires a much smaller quantity of sorbent and solvent, saving time and labor. DSPE was included as a novel clean-up for the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) technique. The principal advantages of DSPE are its simplicity, repeatability, low cost, speed and wide applicability to different type of samples and analytes. The aim of this work was to develop a simple, fast, inexpensive and robust methodology for the determination of PBDEs in biological samples by GC?MS/MS. The proposed technique includes double step sample preparation technique based on single-phase solvent extraction by using ultrasound assisted leaching (USAL), followed by DSPE. Different solvent mixtures, sorbent type and amount, and lipid digestion procedures were evaluated in terms of clean-up and extraction efficiency. The analytical performance of DSPE-GC?MS/MS methodology was evaluated in terms of method detection limits (MDLs), repeatability and linear working range for each studied analyte. Validation of the methodology was carried out by analyzing spiked and real samples of biological nature (fish, egg and chicken) with different lipid content as well as reference material (WELL-WMF-01). Finally, the optimized methodology was applied for the analysis of different types of biological samples of biological, environmental and food safety interest.