Ionic liquid-based membrane-protected micro-solid-phase extraction of organochlorine pesticides in environmental water samples

In this work, two new ionic liquids (4-methylbenzenaminium tetrachloroferrate (III) and 1-naphthylammonium tetrachloroferrate (III)) were synthesized and utilized for the extraction of organochlorine pesticides (OCPs) from environmental water samples. The ionic liquids were characterized by Fourier Transform Infrared spectroscopy, UV–Vis spectroscopy, and scanning electron microscopy. The ionic liquids existed in solid-phase below 65 °C. Thus, they were utilized as sorbent material in stir-bar supported membrane protected micro-solid-phase extraction of OCPs from aqueous samples. The parameters affecting the extraction performance of SB-µ-SPE, such as the amount of sorbent, desorption solvent and its volume, salting-out effect, extraction and desorption times, were optimized. The extracted analytes were analyzed by GC–MS. Under the optimized extraction conditions, analytical figures of merit of SB-µ-SPE-GC-MS were evaluated. Different linear ranges (1–100, 4–100, 10–100 µg/L) were obtained for the target OCPs with correlation coefficients ranged between 0.9943 and 0.9992. The intra-day and inter-day relative standard deviations ranged between 3.9 and 12.5%. The limits of detection ranged from 0.25 to 3.4 µg/L.