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A novel and sensitive magnetic ionic liquid-based up-and-down-shaker-assisted dispersive liquid-liquid microextraction (MIL-UDSA-DLLME) was developed for the graphite furnace atomic absorption spectrometric measurement of inorganic selenium speciation from various rice matrixes. In the first microextraction step, the magnetic ionic liquid (1-butyl-3-methylimidazolium tetrachloroferrate, [C4mim][FeCl4]) was selected to extract the complex of Se(IV) and 2,3-diaminonaphthalene from aqueous solution by the assistance of up-and-down-shaker vortex agitator. After the microextraction step, the magnetic ionic liquid containing target analytes was collected at the bottom of the tube by applying an external magnetic field around the test tube. Under the optimized conditions, the method present has low detection limit (0.018 μg L−1), wide linear dynamic range (0.03–10 μg L−1), and good repeatability (

A novel, simple and rapid method based on magnetic effervescent tablet-assisted ionic liquid dispersive liquid-liquid microextraction (MEA-IL-DLLME) followed by graphite furnace atomic absorption spectrometry (GFAAS) determination was established for the speciation of selenium in various food and beverage samples. In the procedure, a special magnetic effervescent tablet containing CO2 sources (sodium carbonate and sodium dihydrogenphosphate), ionic liquids and Fe3O4 magnetic nanoparticles (MNPs) was used to combine extractant dispersion and magnetic recovery procedures into a single step. The parameters influencing the microextraction efficiency, such as pH of the sample solution, volume of ionic liquid, amount of MNPs, concentration of the chelating agent, salt effect and matrix effect were investigated and optimised. Under the optimised conditions, the limits of detection (LODs) for Se(IV) were 0.021 μg l(-)(1) and the linear dynamic range was 0.05-5.0 μg l(-)(1). The relative standard deviation for seven replicate measurements of 1.0 μg l(-)(1) of Se(IV) was 2.9%. The accuracy of the developed method was evaluated by analysis of the standard reference materials (GBW10016 tea, GBW10017 milk powder, GBW10043 Liaoning rice, GBW10046 Henan wheat, GBW10048 celery). The proposed method was successfully applied to food and beverage samples including black tea, milk powder, mushroom, soybean, bamboo shoots, energy drink, bottled water, carbonated drink and mineral water for the speciation of Se(IV) and Se(VI) with satisfactory relative recoveries (92.0-108.1%).