Flow-Assisted Electro-Enhanced Solid-Phase Microextraction for the Determination of Haloethers in Water Samples

Haloethers represent a special class of disinfection byproducts which pose serious harms to humans and are carcinogenic at parts per billion levels. Flow-assisted electro-enhanced solid-phase microextraction (FA-EE-SPME) method was developed for the determination of 4-chlorophenyl phenyl ether (CPPE) and 4-bromophenyl phenyl ether (BPPE) in large volumes of water samples. Within the extraction system, different commercial SPME fibers were exposed into a 100 mL sample flowing at a rate of 50 mL min⁻¹ via direct immersion mode for extraction of target analytes. The major factors affecting the extraction efficiency such as absorption time, pump flow rate, ionic strength, applied potential, sample pH and SPME fiber type were optimized using one factor at-a-time approach. After extraction, the SPME fiber was desorbed in the injector port of gas chromatography–mass spectrometry (GC–MS). The proposed method combines advantages of electrical potential and flow system together to enhance extraction efficiency of SPME. Quantification was carried out over a concentration range of 0.5–100 µg L⁻¹ and good linearity was obtained with detection limits of 0.05 and 0.07 µg L⁻¹, respectively, for CPPE and BPPE. The relative standard deviation of the calibrations was in the range of 1.1 and 3.6 %. Application of FA-EE-SPME was tested for various drinking and tap water samples collected from Eastern Province of Saudi Arabia and the method performance was compared with reported literature values.