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High-Resolution Mass Spectrometric Techniques for Structural Characterization and Determination of Organic Pollutants in the Environment
Published in Leo M. L. Nollet, Dimitra A. Lambropoulou, Chromatographic Analysis of the Environment, 2017
Cortés-Francisco Nuria, Caixach Josep
Data-dependent acquisition mode can help to have enough time to perform additional MS/MS scans. The mass analyzers operate at full scan (or selected ion monitoring [SIM]) and by data-dependent mode, a fixed number of peaks selected from a survey scan using predetermined rules are selected, and the corresponding ions are subjected to MS/MS analysis (Murray, 2010). The predetermined rules may include a list of m/z precursors, reject list, dynamic exclusion, signal- to-noise threshold, loop count, and multiplex (Michalski et al., 2011; Kumar et al., 2013). The data-dependent mode may seem to be a semiautomatic way of performing MS/MS. However, meticulous optimization of some parameters is crucial, to prevent the mass analyzer to perform MS/MS of a solvent or contaminant ion, especially when ions are coeluting.
Field Study
Published in Stephanie Fiorenza, Carroll L. Oubre, C. Herb Ward, M.K. Banks, R.S. Govindaraju, A.P. Schwab, P. Kulakow, J. Finn, Phytoremediation of Hydrocarbon-Contaminated Soil, 2020
Stephanie Fiorenza, Carroll L. Oubre, C. Herb Ward, M.K. Banks, R.S. Govindaraju, A.P. Schwab, P. Kulakow, J. Finn
The biomarkers and PAHs were analyzed by a Hewlett-Packard Model 6890 gas chro-matograph equipped with a mass selective detector as described in Section 2.1. To achieve high sensitivity and low detection limits, specific ions were selected for each target analyte quantification by using selected ion monitoring (SIM). The quantitation ions are listed in Table 3.6. A recovery study was executed to ensure that the target compounds were quantitatively extracted from the soil, recovered from the chromatography column during separation, and properly analyzed by the GC/MS. Recoveries for typical compounds (phenanthrene, benzo[a]anthracene, pyrene, and benzo[a]pyrene) ranged from 97 to 103%.
2 Nanoparticle-Encapsulating Poly(vinyl chloride) (TEPVC) compared to conventional PVC
Published in Matthew Laudon, Bart Romanowicz, 2007 Cleantech Conference and Trade Show Cleantech 2007, 2019
H. Yoo, S. H. Kim, A. R. Lee, S.-Y. Kwak Kwak
HRGC/HRMS was preformed on a Waters Micromass Autospec Ultima mass spectrometer fitted with an Agilent HP6890 GC. SP-2331 (SUPELCO 60 m (length), 0.32 mm (internal diameter), 0.20 pm (film thickness)) coupled to DB-17HT (J & W 30 m, 0.32 mm, 0.15 pm) capillary column was applied to the determination of PCDD/PCDF congeners and HT8-PCB (SGE 60 m, 0.25 mm) capillary column was applied to determination of coplanar PCBs. The mass spectrometer was operated in selected ion monitoring mode (SIM) at a resolution > 10,000 and two ions were monitored for each congener group.
Occurrence of phthalates in facemasks used in India and its implications for human exposure
Published in International Journal of Environmental Health Research, 2022
Nandini Shende, Girivyankatesh Hippargi, Suyog Gurjar, Asirvatham Ramesh Kumar, Sadhana Rayalu
PAEs were analyzed by gas chromatography-mass spectrometry (GC-MS, Perkin Elmer, Clarus SQ8C) equipped with an SLB 5 MS capillary column (30 m × 0.25 mm × 0.25 µm). The optimized GC parameters were as follows: injection volume: 2 µl; injector: 310 ℃, oven temperature initial: 100 ℃ for 0.5 min, then increased to 320 ℃ at a rate of 15 ℃/min, hold time at 320 ℃ for 2.5 min. Helium was used as carrier gas at the flow rate of 1 ml/min. The mass spectrometer parameters were as follows: inlet line temperature: 300 ℃, ion source temperature: 280 ℃. The selected ion monitoring (SIM) mode was used for quantitation. The most abundant ion of PAEs was m/z 149, except for DMP, where the most abundant ion was m/z 163. The chromatograph of GC-MS is incorporated in supporting information Figure SF1. In addition, other ions such as m/z 163, 222, etc., were also used as qualifier ions. Information about quantifier, qualifier, retention time (RT), LOD, and LOQ are provided in Table 1.
Skin transferability of phthalic acid ester plasticizers and other plasticizers using model polyvinyl chloride sheets
Published in Journal of Environmental Science and Health, Part A, 2020
Tsuyoshi Kawakami, Kazuo Isama, Hideto Jinno
A Focus GC/DSQ II or Trace GC/Quantum XLS (both manufactured by Thermo Fisher Scientific Inc.) was used to measure the PAEs in sample solutions. For the capillary columns, Factor Four VF-5MS (length 30 m, internal diameter 0.25 mm, film thickness 0.25 μm; manufactured by Varian, Inc.) was used for Focus GC, and DB-5MS (length 30 m, internal diameter 0.25 μm, film thickness 0.25 μm; manufactured by J&W-Agilent) was used for Trace GC. Helium was used as the carrier gas, and the flow rate was set at 1 mL/min. The temperatures of the injection port, transfer line, and ion source were set at 250 °C (Trace GC: 230 °C), 280 °C, and 250 °C respectively, and 1 μL of sample solution was injected in splitless mode. The column oven temperature program was set to remain at the initial temperature of 60 °C for 2 min, then increases to 310 °C at 20 °C/min, and set to remain at 310 °C for 10 min. Electron ionization (EI) was used as the ionization technique, and the ionization voltage was set to 70 eV. Samples were measured in the selected ion monitoring (SIM) mode. Quantification and qualification ions and other parameters for the PAEs and other compounds are presented in Table 1.
Determination of volatile organic compounds (VOCs) levels from various smoking cessation aids by using gas chromatography-mass spectrometry methodology
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Yong-Yeon Kim, Min-Kyung Kim, Han-Seung Shin
GC-MS analysis of VOCs was undertaken using an Agilent Technologies 7820A/5975 C MSD GC-MS system (Agilent Technologies, Santa Clara, CA) installed with a DB-5 MS column (60.0 m × 0.32 mm I.D., 0.5 μm particle size). The oven temperature was set to 40°C, held for 5 min, ramped at 15°C/min to 180°C, and held for 6 min. A post-run was set at 310°C, held for 12 min. The mass spectrometer was operated in selected ion monitoring (SIM) mode. The highest purity of helium (99.99%) was used as the carrier gas with a flow rate of 1.3 mL/min. The sample solution was injected in split mode (30:1) at 160°C, and the injection volume was 3.0 μL. The MS source temperature was 240°C. Each of the six VOCs and IS have one target ion (underlined) and two qualifier ions. The selected ions were 51, 78, and 77 for benzene; 65, 91, and 92 for toluene; 78, 104, and 103 for styrene; and 53, 67, and 68 for isoprene; and 51, 53, and 52 for acrylonitrile; 54, 39, and 53 for 1,3-butadiene; and 56, 84.1, 82.1 for benzene-d6 (IS). Confirmation of the identity of the VOCs was based upon the molecular mass and extracted ion chromatograms using the GC-MS analysis program. The HS autosampler attached to the GC-MS was a Dani 86.50 HSS Plus (DANI Instruments SpA, Cologno Monzese, Italy). Each 20-mL HS vial contained 1 mL of sample. The operating conditions were as follows: vial incubation temperature, 90°C; vial incubation time, 1,200 s; vial mixing, hard; HS loop temperature (loop temp), 110°C; HS transfer line temperature, 120°C; probe out time, 1.3 min; vial pressure gas, helium; carrier gas pressure, 0.16 bar, valve pressure, 0.65 bar; press ON/OFF time 0.07/0.40 min; sampling ON/OFF, 0.60/1.20 min; vent ON/OFF, 0.40/0.60 min.