A novel approach to automation of dynamic hollow fiber liquid-phase microextraction

An automated dynamic two‐phase hollow fiber microextraction apparatus combined with high‐performance liquid chromatography was developed for extraction and determination of chlorophenoxy acid (CPA) herbicides from environmental samples. The extraction device, called TT‐extractor, consists of a polypropylene hollow fiber mounted inside a stainless steel tube by means of two tee‐connectors in flow system. An organic solvent, which fills the lumen and the pores of the hydrophobic fiber, is pumped through the fiber repeatedly and the sample is pumped along the outer side of the fiber. The factors affecting the dynamic hollow fiber liquid‐phase microextraction (DHF‐LPME) of target analytes were investigated and the optimal extraction conditions were established. To test the applicability of the designed instrument, CPAs were extracted from environmental aqueous samples. The limits of detection (LODs) as low as 0.5 μg/L, linear dynamic range in the range of 1–100 μg/L and the relative standard deviations of