Solid-Phase Extraction Combined with Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Simultaneous Determination of Organochlorine Pesticides and Polychlorinated Biphenyls in Fish

Abstract

Solid-phase extraction (SPE) was combined with dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) as a pretreatment technique for the simultaneous analysis of 11 organochlorine pesticides (OCPs) and 5 polychlorinated biphenyls (PCBs) in fish tissue. Gas chromatography with electron capture detector was used for the identification and quantification of these compounds. In the newly developed method, the acetonitrile extractant of the fish sample was cleaned up by commercialized SPE cartridges packed with acid alumina, and then mixed with water, sodium-chloride, and n-pentadecane for the purpose of target analyte enrichment via DLLME-SFO process. Effect of the parameters including SPE packing material, amount and chemical nature of extraction solvent, water volume, and salt concentration on the signal responses were investigated, and the recoveries of this method ranged between 70.1% and 112.3% at three spiked levels under the optimized conditions. The calibration curves were found to be linear in the range of 1.56–312.5 μg L−1, and the limits of detection ranged from 0.372 to 1.12 μg kg−1. Comparing the other reported pretreatment method, the presented one was sensitive, time-saving, and environmentally friendly.