title: Liquid-phase microextraction by solidification of floating organic microdrop and GC-MS detection of trihalomethanes in drinking water.
abstract: A simple and sensitive methodology based on liquid-phase microextraction (LPME) followed by GC-MS, was developed for the determination of trihalomethanes (THMs) in drinking water. A microdrop of organic solvent was floated on the surface of the aqueous sample and it was agitated for a desired time. Then, the sample vial was cooled by inserting it into an ice bath for 4 min. The solidified solvent was transferred into a suitable vial and immediately melted. The extract was directly injected into the GC. Microextraction efficiency factors were investigated and optimized: 7 muL 1-undecanol microdrop exposed for 15 min floated on the surface of a 10.0 mL aqueous sample with the temperature of 60 degrees C containing 3 M of NaCl and stirred at 750 rpm. Under the selected conditions, enrichment factors (EFs) up to 482-fold, LOD of 0.03-0.08 mug/L (S/N = 3) and dynamic linear ranges of 0.10-100 mug/L were obtained. A reasonable repeatability (RSD < 8.6%, n = 8) with satisfactory linearity (r(2) greater, not dbl equals 0.9947) of results illustrated a good performance of the present method. The protocol proved to be rapid, cost-effective, and is a green procedure for the screening purposes.
authors.affiliation: Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran,Tehran, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Farahani
authors.forename: Parviz
authors.initials: P
authors.lastname: Norouzi
authors.forename: Rassoul
authors.initials: R
authors.lastname: Dinarvand
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ganjali
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*; D056656:Lab-On-A-Chip Devices; D046208:Microchip Analytical Procedures / Q000379:methods*; D055601:Organic Chemistry Phenomena; D009994:Osmolar Concentration; D012996:Solutions; D012997:Solvents; D013696:Temperature; D013997:Time Factors; D022882:Trihalomethanes / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
chemical_list: D012996:Solutions; D012997:Solvents; D022882:Trihalomethanes