2.4 Extraction procedureA schematic

2.4 Extraction procedure
A schematic presentation of the proposed microfunnel-filterbased
emulsification microextraction is shown in Figure 1.
The method provides an extraction process in a few minutes,
and to perform it, initially, 45 mL of the aqueous sample
solution was poured in a 50 mL cylindrical glass vial, and
250 μL of the organic solvent (dihexyl ether) was added.
The solvent was dispersed as tiny droplets in the sample
solution by repeated suction of the mixture from the vial and
dispensing it into the vial using a simple glass syringe (for ten
times). Then the mixture was passed through a nylon syringe
filter to separate the phases. This filter was permeable to a
broad range of solvents, and along with passing the mixture
through it, fine droplets of the organic phase were aggregated,
separated from the aqueous sample solution, and floated
(100 μL). Finally, using a micro-funnel and adding a few
milliliters of ultrapure water into the vial through the rubber
cap, the floating extractant was raised, narrowed into the
capillary part of micro-funnel, and collected using a microsyringe,
and 2 μL of the extractant phase was transferred to
the gas chromatograph for the final analysis.