title: A novel approach to evaluate the extent and the effect of cross-contribution to the intensity of ions designating the analyte and the internal standard in quantitative GC-MS analysis.
abstract: In gas chromatography-mass spectrometry methods of analysis adopting the analyte's isotopic analog as the internal standard (IS), the cross-contribution (CC) phenomenon -- contribution of IS to the intensities of the ions designating the analyte, and vice versa -- has been demonstrated to affect the quantitation data. A novel approach based on the deviations of the empirically observed concentrations of a set of standards was developed to assess the accuracy of the empirically derived CC data. This approach demonstrated that normalization of ion intensities derived from the analyte and the IS generates reliable CC data. It further demonstrated that an ion-pair (designating the analyte and the IS) with approximately 5% or higher CC will result in a very limited linear calibration range.
authors.affiliation: Department of Medical Technology, Fooyin University, Kaohsiung, Taiwan.
authors.forename: Bud-Gen
authors.initials: BG
authors.lastname: Chen
authors.forename: Chiung Dan
authors.initials: CD
authors.lastname: Chang
authors.forename: Chia-Ting
authors.initials: CT
authors.lastname: Wang
authors.forename: Yi-Jun
authors.initials: YJ
authors.lastname: Chen
authors.forename: Wei-Tun
authors.initials: WT
authors.lastname: Chang
authors.forename: Sheng-Meng
authors.initials: SM
authors.lastname: Wang
authors.forename: Ray H
authors.initials: RH
authors.lastname: Liu
mesh_terms: D015104:3,4-Methylenedioxyamphetamine / Q000032:analysis; D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods* / Q000592:standards*; D004091:Hydromorphone / Q000032:analysis; D007477:Ions / Q000737:chemistry*; D012015:Reference Standards; D015203:Reproducibility of Results
chemical_list: D007477:Ions; D015104:3,4-Methylenedioxyamphetamine; D004091:Hydromorphone