title: Application of flat polymer membrane microextraction for the continuous detection of trihalomethanes in aqueous matrices.
abstract: A module was developed for the continuous monitoring of volatile halogen organic pollutants in complex matrices. The module utilized a polymer membrane for extraction and a capillary gas chromatography-mass spectrometry (GC-MS) for detection. The extraction of analytes (CHCl(3), CHCl(2)Br, CHClBr(2) and CHBr(3)) from samples was performed in a flow system mediated by a non-porous flat membrane. The effects of the phase-volume ratios, flow conditions, kinetics, analyte properties and matrices were assessed and optimized. The limits of detection were at low microg L(-1) to ng L(-1) levels, with GC-MS analysis under selected ion monitoring (SIM), whereas enrichment factors between 6 and 30 were achieved. Precision values calculated as repeatability and reproducibility with a relative standard deviation (%RSD, n = 5) of 7.2 to 9.5 after 30 min were obtained. The performance of the continuous membrane assisted solvent extraction system was compared with classical liquid-liquid extraction. The method was applied to the extraction of trihalomethanes in chlorinated drinking-water samples.
authors.affiliation: Institut für Technischen Umweltschutz, Fachgebiet Umweltverfahrenstechnik, Technische Universität Berlin, Germany. carmen.gal@web.de
authors.forename: Carmen
authors.initials: C
authors.lastname: Gal
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Remus
authors.initials: R
authors.lastname: Nutiu
mesh_terms: D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D007700:Kinetics; D008567:Membranes, Artificial; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D022882:Trihalomethanes / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
chemical_list: D008567:Membranes, Artificial; D011108:Polymers; D022882:Trihalomethanes; D014874:Water Pollutants, Chemical