The fibre was soaked in
commonly used solvents 1-octanol and 1-undecanol for 15 s to
impregnate the pores, and the lumen of the prepared fibre piece was filled with 15 lL extraction solvent using a microsyringe carefully.
Both open ends of the fibre were sealed by a piece of aluminium
foil. Then the hollow fibre was bent to a U-shape and
immersed in the 5 mL sample solution containing 100 ng mL1 of
each oestrogen and a 10 6 mm magnetic stirrer bar and stirring
for 2 and 40 min, respectively. Then, the fibre was removed from
the sample solution, and its closed end was cut. Then 200 lL methanol
was injected into one of its end by a microsyringe. Finally the
extract was filtered by a 0.45 lm membrane and injected into the
HPLC system for analyses.