The porous hollow fibre used to support the organic phase
was Q3/2 polypropylene (Wuppertal, Germany) with 600 lm inner
diameter, 200 lm of wall thickness and pores of 0.2 lm. A 1.0 mL
microsyringe (model 702SNR) with a sharp needle tip was used for
the injection of the extraction solvent into the hollow fibre lumen.