title: Differentiation and quantification of xylene isomers by combining headspace solid-phase microextraction/gas chromatography and self-ion molecule reaction in an ion trap tandem mass spectrometry.
abstract: A headspace solid-phase microextraction (HS-SPME) method using polydimethylsiloxane (PDMS)-coated fiber coupling with GC/self-ion molecule reaction (SIMR)/MS/MS (GC/SIMR/MS/MS) has been developed for the differentiation of o-, m-, and p-xylene isomers. The optimization parameters of this method are: extraction time 20 min, stirring rate 1200 rpm, sampling temperature 28 degrees C, and salt concentration 5%. The LODs were found to be in the range of 3-9 ng/mL under the SIM mode of GC/MS. The RSDs were below 1% (n=5). The linear dynamic range of the calibration curve was from 0.05 to 10.0 microg/mL with correlation coefficient (r2)>0.9089. The advantages of this technique are sensitive, selective, ease of operation, simple device, solvent free, and extremely little sample consumption. This technique is the first example using SIMR combined MS/MS applied in the GC/MS and it can be applied to other volatile compounds for future application.
authors.affiliation: Department of Chemistry, Tamkang University, Tamsui, Taipei Hsien, Taiwan, ROC.
authors.forename: Chih-Hao
authors.initials: CH
authors.lastname: Yang
authors.forename: Nadeem Ahmad
authors.initials: NA
authors.lastname: Khan
authors.forename: Hui-Fen
authors.initials: HF
authors.lastname: Wu
mesh_terms: D002138:Calibration; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods; D007477:Ions / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012965:Sodium Chloride / Q000737:chemistry; D052617:Solid Phase Microextraction / Q000295:instrumentation / Q000379:methods*; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D013696:Temperature; D013997:Time Factors; D014992:Xylenes / Q000032:analysis*
chemical_list: D007477:Ions; D014992:Xylenes; D012965:Sodium Chloride