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Effervescence-assisted dispersive micro-solid phase extraction

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In 2011 a new sample pre-treatment technique, called Effervescence-assisted dispersive micro-solid phase extraction, was proposed. The technique was based on the use of an effervescent reaction (reaction between a proton donor and a carbonate source releasing gaseous CO 2 ) for the efficient dispersion of a sorbent. For this purpose a lab-made effervescent tablet, containing all the reagents necessaries to perform the dispersive extraction (NaH 2 PO 4 ) as proton donor, Na 2 CO 3 as carbonate source and the appropriate sorbent) is directly added to the sample. The tablet, which is 250 mg in weight and 102 mm in diameter, is produced by the simple blending of the precursors and their final compression in a hydraulic manual press. The final tablets are stable enough if they are stored under inert atmosphere to preserve them from the environmental humidity, which reduces the CO 2 releasing potential and dispersion efficiency. The tablet composition is optimized considering the effe