Journal articles: 'Td-Gc-Ms/ms'

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Timkovsky, J., A. W. H. Chan, T. Dorst, A. H. Goldstein, B. Oyama, and R. Holzinger. "Organic aerosol composition measurements with advanced offline and in-situ techniques during the CalNex campaign." Atmospheric Measurement Techniques Discussions 7, no. 12 (December 12, 2014): 12449–80. http://dx.doi.org/10.5194/amtd-7-12449-2014.

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Abstract. Our understanding of formation processes, physical properties and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in-situ thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) and offline two-dimensional gas chromatography with a time-of-flight mass spectrometer (GC×GC/TOF-MS). 153 compounds were identified using the GC×GC/TOF-MS, 123 of which were matched with 64 ions observed by the TD-PTR-MS. A reasonable overall correlation of 0.67 (r2) was found between the total matched TD-PTR-MS signal (sum of 64 ions) and the total matched GC×GC/TOF-MS signal (sum of 123 compounds). A reasonable quantitative agreement between the two methods was observed for most individual compounds with concentrations which were detected at levels above 2 ng m−3 using the GC×GC/TOF-MS. The analysis of monocarboxylic acids standards with TD-PTR-MS showed that alkanoic acids with molecular masses below 290 amu are detected well (recovery fractions above 60%). However, the concentrations of these acids were consistently higher on quartz filters (quantified offline by GC×GC/TOF-MS) than those suggested by in-situ TD-PTR-MS measurements, which is consistent with the semivolatile nature of the acids and corresponding positive filter sampling artifacts.

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Timkovsky, J., A. W. H. Chan, T. Dorst, A. H. Goldstein, B. Oyama, and R. Holzinger. "Comparison of advanced offline and in situ techniques of organic aerosol composition measurement during the CalNex campaign." Atmospheric Measurement Techniques 8, no. 12 (December 10, 2015): 5177–87. http://dx.doi.org/10.5194/amt-8-5177-2015.

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Abstract. Our understanding of formation processes, physical properties, and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in situ thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) and offline two-dimensional gas chromatography with a time-of-flight mass spectrometer (GC × GC/TOF-MS). Using the GC × GC/TOF-MS 153 compounds were identified, 123 of which were matched with 64 ions observed by the TD-PTR-MS. A reasonable overall correlation of 0.67 (r2) was found between the total matched TD-PTR-MS signal (sum of 64 ions) and the total matched GC × GC/TOF-MS signal (sum of 123 compounds) for the Los Angeles area. A reasonable quantitative agreement between the two methods was observed for most individual compounds with concentrations which were detected at levels above 2 ng m−3 using the GC × GC/TOF-MS. The analysis of monocarboxylic acids standards with TD-PTR-MS showed that alkanoic acids with molecular masses below 290 amu are detected well (recovery fractions above 60 %). However, the concentrations of these acids were consistently higher on quartz filters (quantified offline by GC × GC/TOF-MS) than those suggested by in situ TD-PTR-MS measurements, which is consistent with the semivolatile nature of the acids and corresponding positive filter sampling artifacts.

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Fahrenholtz, Svea, Xaver Baur, and Lygia T. Budnik. "Analytik von Begasungsmitteln mittels TD-GC-MS." Zentralblatt für Arbeitsmedizin, Arbeitsschutz und Ergonomie 60, no. 6 (June 2010): 192–94. http://dx.doi.org/10.1007/bf03344277.

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Yue, Xiaochen, Juntao Chen, Yafeng Yang, Zhenling Liu, Ting Wang, and Wanxi Peng. "Chemical components of Choerospondias axillaris wood by TD-GC/MS, Py-GC/MS, and TG." Journal of King Saud University - Science 32, no. 1 (January 2020): 1142–46. http://dx.doi.org/10.1016/j.jksus.2019.10.010.

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Jurczak, Rafał. "Analiza mikrośladów trinadtlenku triacetonu (TATP) w fazie gazowej z zastosowaniem TD-GC/MS." Przegląd Bezpieczeństwa Wewnętrznego 13, no. 24 (2021): 250–76. http://dx.doi.org/10.4467/20801335pbw.21.007.13564.

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W artykule opisano metodykę wykrywania trinadtleneku triacetonu (TATP) w postaci par oraz śladów powierzchniowych z wykorzystaniem chromatografi gazowej sprzężonej ze spektrometrią mas wyposażoną w system do termodesorpcji (TD-GC/MS). Rozwiązania techniczne aparatury analitycznej umożliwiają wybór jednej z dwóch metod wprowadzenia par analitu w celu identyfikacji – pośrednio ze złoża TENAX TA lub bezpośrednio z obiektów badań. Dodatkowo zastosowanie elementu GERSTEL CIS odgrywającego rolę koncentratora substancji powoduje, że jest możliwa identyfikacja już nawet nanośladowych ilości TATP. W artykule przedstawiono schemat działania termodesorpcji w TD-GC/MS z jednoczesnym zwróceniem uwagi na cechy fizyczne substancji warunkujące osiągnięcie zadowalających wyników. Micro-traces analysis of triacetone triperoxide (TATP) in the form of vapours using TD-GC/MS The article discusses the method of detecting triacetone triperoxide (TATP) in the form of vapours and surface traces using gas chromatography with a thermal desorption system of mass spectrometry (TD-GC/MS). The technical solutions of analytical equipment make it possible to choose one or two methods for introducing analyte vapour for identification – indirectly from the TENAX TA deposit or directly from the research objects. In addition, the use of the GERSTEL CIS element as a substance concentrator renders identification of even nano-trace amounts of TATP possible. The article presents the experimental procedure of the thermal desorption TD-GC/MS and simultaneously draws attention to physical properties of the substance determining the achievement of satisfactory results.

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Moufid, Mohammed, Michael Hofmann, Nezha El Bari, Carlo Tiebe, Matthias Bartholmai, and Benachir Bouchikhi. "Wastewater monitoring by means of e-nose, VE-tongue, TD-GC-MS, and SPME-GC-MS." Talanta 221 (January 2021): 121450. http://dx.doi.org/10.1016/j.talanta.2020.121450.

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Watanabe, Atsushi, Chu Watanabe, Robert Freeman, Mari Nakajima, Norio Teramae, and Hajime Ohtani. "QUANTITATIVE ANALYSIS OF FATTY ACIDS IN VULCANIZED STYRENE–BUTADIENE RUBBER BY THERMAL DESORPTION AND THERMALLY ASSISTED HYDROLYSIS AND METHYLATION-GC/MS." Rubber Chemistry and Technology 87, no. 3 (September 1, 2014): 516–25. http://dx.doi.org/10.5254/rct.14.86941.

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ABSTRACT Determination of stearic acid in rubber is very important from the viewpoint of quality control of products. In place of the conventional liquid-phase extraction procedures for the analysis of additives in rubber, stearic and palmitic acids in vulcanized styrene–butadiene rubber (SBR) samples were directly analyzed in the solid state by thermal desorption (TD)–gas chromatography (GC)/mass spectrometry (MS) and thermally assisted hydrolysis and methylation (THM)–GC/MS. It was found that the precision of analytical data was only fair in the TD-GC/MS analysis, with 7.8% relative standard deviation (RSD), because of the interaction between the polar fatty acids and basic sites in the GC chromatographic system. On the other hand, THM-GC/MS, in which the fatty acids are derivatized to the methyl esters using tetramethylammonium hydroxide, can overcome this problem. Under the optimized measurement conditions of this study for THM-GC/MS, the average determined value (0.62 wt%) of total fatty acids in the SBR samples was found to agree well with the compounded amount (0.64 wt%) used in the preparation stage of the SBR samples, and the RSD was 3.2%.

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Elorduy, Iñaki, Nieves Durana, José Antonio García, María Carmen Gómez, and Lucio Alonso. "Optimization and Validation of Thermal Desorption Gas Chromatography-Mass Spectrometry for the Determination of Polycyclic Aromatic Hydrocarbons in Ambient Air." Journal of Analytical Methods in Chemistry 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/8734013.

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Thermal desorption (TD) coupled with gas chromatography/mass spectrometry (TD-GC/MS) is a simple alternative that overcomes the main drawbacks of the solvent extraction-based method: long extraction times, high sample manipulation, and large amounts of solvent waste. This work describes the optimization of TD-GC/MS for the measurement of airborne polycyclic aromatic hydrocarbons (PAHs) in particulate phase. The performance of the method was tested by Standard Reference Material (SRM) 1649b urban dust and compared with the conventional method (Soxhlet extraction-GC/MS), showing a better recovery (mean of 97%), precision (mean of 12%), and accuracy (±25%) for the determination of 14 EPA PAHs. Furthermore, other 15 nonpriority PAHs were identified and quantified using their relative response factors (RRFs). Finally, the proposed method was successfully applied for the quantification of PAHs in real 8 h-samples (PM10), demonstrating its capability for determination of these compounds in short-term monitoring.

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Li, Meng, Bicheng Lin, and Binling Zhu. "Rapid Screening of Etomidate and Its Analogs in Seized e-Liquids Using Thermal Desorption Electrospray Ionization Coupled with Triple Quadrupole Mass Spectrometry." Toxics 12, no. 12 (December 5, 2024): 884. https://doi.org/10.3390/toxics12120884.

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The growing popularity of e-cigarettes has raised significant concerns about the safety and potential abuse of these products. Compounds originally used in the medical field, such as etomidate, metomidate, and isopropoxate, have been illegally added to e-liquids, posing substantial risks to consumer health, and facilitating the misuse of illicit drugs. To address these concerns, this study developed a rapid and efficient method for detecting etomidate, metomidate, and isopropoxate in e-liquids using thermal desorption electrospray ionization coupling triple quadrupole mass spectrometry (TD-ESI/MS/MS). The TD-ESI/MS/MS method exhibits high sensitivity, with detection limits for etomidate, metomidate, and isopropoxate reaching 3 ng/mL. Screening of 70 seized e-liquid samples from 12 cases using TD-ESI/MS/MS revealed that 46 samples contained only etomidate, 13 samples contained only isopropoxate, and 11 samples contained both etomidate and metomidate. The qualitative results obtained from TD-ESI/MS/MS were in complete agreement with those of GC-MS. Moreover, the TD-ESI/MS/MS method requires no pre-treatment steps and has a detection time of only 1 min, thereby saving experimental consumables and significantly reducing detection time. The method demonstrated high sensitivity, accuracy, and reproducibility, making it suitable for high-throughput screening in forensic and regulatory settings.

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Ahmed, Waqar M., Pavlos Geranios, Iain R. White, Oluwasola Lawal, Tamara M. Nijsen, Michael J. Bromley, Royston Goodacre, Nick D. Read, and Stephen J. Fowler. "Development of an adaptable headspace sampling method for metabolic profiling of the fungal volatome." Analyst 143, no. 17 (2018): 4155–62. http://dx.doi.org/10.1039/c8an00841h.

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Lin, Xing-Tao, Ge Sun, Jing-Qiang Zhao, Ling-Li Tang, Sheng-Hua Li, and Ya-Bo Xie. "UiO-66 Selective Enrichment Integrated with Thermal Desorption GC-MS for Detection of Benzene Homologues in Ambient Air." Journal of Analytical Methods in Chemistry 2021 (December 14, 2021): 1–9. http://dx.doi.org/10.1155/2021/3138436.

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In this study, UiO-66 was selected as sorbent media packed in the tube to selectively enrich trace levels of benzene homologues such as benzene, toluene, and xylene (BTX) in ambient air prior to thermal desorption (TD)-GC-MS determination. A series of experiments were conducted to obtain the optimal TD conditions. The results indicated that the optimal TD parameters were as follows: desorption temperature of 180°C, desorption flow rate of 50 mL min−1, and desorption time of 30 min. Furthermore, the method based on UiO-66 enrichment integrated with TD-GC-MS for trace levels of BTX was successfully developed. It exhibited a good linearity (R2 > 0.99) in the range of 50–1000 ng, except for p, m-xylene in the range of 100–2000 ng, and achieved the recovery of 69.4–101.3%, and the relative standard deviation of 3.8–6.4%. The detection limits of BTX were 1.6–4.0 ng; according to 10 L of sampling volume, the method detection limits would be in the range of 0.16–0.40 µg m−3. Additionally, the method was successfully applied to determine BTX in indoor air and showed good selectivity and sensitivity. In summary, the findings in this work revealed that UiO-66 was an attractive adsorbent for selective enrichment trace levels of BTX compounds in ambient air, which was favorable for the subsequent detection by TD-GC-MS.

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Michoud, Vincent, Elise Hallemans, Laura Chiappini, Eva Leoz-Garziandia, Aurélie Colomb, Sébastien Dusanter, Isabelle Fronval, et al. "Molecular characterization of gaseous and particulate oxygenated compounds at a remote site in Cape Corsica in the western Mediterranean Basin." Atmospheric Chemistry and Physics 21, no. 10 (May 26, 2021): 8067–88. http://dx.doi.org/10.5194/acp-21-8067-2021.

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Abstract. The characterization of the molecular composition of organic carbon in both gaseous and aerosol is key to understanding the processes involved in the formation and aging of secondary organic aerosol. Therefore a technique using active sampling on cartridges and filters and derivatization followed by analysis using a thermal desorption–gas chromatography–mass spectrometer (TD–GC–MS) has been used. It is aimed at studying the molecular composition of organic carbon in both gaseous and aerosol phases (PM2.5) during an intensive field campaign which took place in Corsica (France) during the summer of 2013: the ChArMEx (Chemistry and Aerosol Mediterranean Experiment) SOP1b (Special Observation Period 1B) campaign. These measurements led to the identification of 51 oxygenated (carbonyl and or hydroxyl) compounds in the gaseous phase with concentrations between 21 and 3900 ng m−3 and of 85 compounds in the particulate phase with concentrations between 0.3 and 277 ng m−3. Comparisons of these measurements with collocated data using other techniques have been conducted, showing fair agreement in general for most species except for glyoxal in the gas phase and malonic, tartaric, malic and succinic acids in the particle phase, with disagreements that can reach up to a factor of 8 and 20 on average, respectively, for the latter two acids. Comparison between the sum of all compounds identified by TD–GC–MS in the particle phase and the total organic matter (OM) mass reveals that on average 18 % of the total OM mass can be explained by the compounds measured by TD–GC–MS. This number increases to 24 % of the total water-soluble OM (WSOM) measured by coupling the Particle Into Liquid Sampler (PILS)-TOC (total organic carbon) if we consider only the sum of the soluble compounds measured by TD–GC–MS. This highlights the important fraction of the OM mass identified by these measurements but also the relative important fraction of OM mass remaining unidentified during the campaign and therefore the complexity of characterizing exhaustively the organic aerosol (OA) molecular chemical composition. The fraction of OM measured by TD–GC–MS is largely dominated by di-carboxylic acids, which represent 49 % of the PM2.5 content detected and quantified by this technique. Other contributions to PM2.5 composition measured by TD–GC–MS are then represented by tri-carboxylic acids (15 %), alcohols (13 %), aldehydes (10 %), di-hydroxy-carboxylic acids (5 %), monocarboxylic acids and ketones (3 % each), and hydroxyl-carboxylic acids (2 %). These results highlight the importance of polyfunctionalized carboxylic acids for OM, while the chemical processes responsible for their formation in both phases remain uncertain. While not measured by the TD–GC–MS technique, humic-like substances (HULISs) represent the most abundant identified species in the aerosol, contributing for 59 % of the total OM mass on average during the campaign. A total of 14 compounds were detected and quantified in both phases, allowing the calculation of experimental partitioning coefficients for these species. The comparison of these experimental partitioning coefficients with theoretical ones, estimated by three different models, reveals large discrepancies varying from 2 to 7 orders of magnitude. These results suggest that the supposed instantaneous equilibrium being established between gaseous and particulate phases assuming a homogeneous non-viscous particle phase is questionable.

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Benanou, D., F. Acobas, and M. R. de Roubin. "Optimization of stir bar sorptive extraction applied to the determination of odorous compounds in drinking water." Water Science and Technology 49, no. 9 (May 1, 2004): 161–70. http://dx.doi.org/10.2166/wst.2004.0560.

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The off-flavour compounds 2-methylisoborneol (MIB), geosmin, 2,4,6-trichloroanisole, 2,3,6-trichloroanisole, 2,3,4-trichloroanisole and 2,4,6-tribromoanisole were analyzed in water samples by Stir Bar Sorptive Extraction (SBSE) followed by on-line thermal desorption (TD)-capillary GC/MS. Quantification was performed using MS in the single ion monitoring mode (SIM) with 2,4,6-trichloroanisol-D5 as internal standard. Quantification limits are 0.1 ng/l to 0.2 ng/l for the haloanisoles, 0.5 ng/l for geosmin and 1 ng/l for MIB. The relative standard deviations at the quantification limit are ranging from 7 to 14.6%. SBSE-recovery was evaluated by spiking real water samples and varied from 87 to 117%. More than twenty samples per day can be analyzed by SBSE-TD-capillary GC-MS. The same technique in combination with olfactometry was used to elucidate unknown odorous compounds in water samples.

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Byliński, Hubert, Paulina Kolasińska, Tomasz Dymerski, Jacek Gębicki, and Jacek Namieśnik. "Determination of odour concentration by TD-GC×GC–TOF-MS and field olfactometry techniques." Monatshefte für Chemie - Chemical Monthly 148, no. 9 (July 13, 2017): 1651–59. http://dx.doi.org/10.1007/s00706-017-2023-8.

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MEHDIKHANI, ALI, HAMID REZA LOTFIZADEH, KAMYAR ARMAN, and HADI NOORIZADEH. "AN IMPROVED QSPR STUDY OF REVERSE FACTOR OF NANOPARTICLES IN ROADSIDE ATMOSPHERE ON KERNEL PARTIAL LEAST SQUARES AND GENETIC ALGORITHM." Journal of Theoretical and Computational Chemistry 12, no. 01 (February 2013): 1250106. http://dx.doi.org/10.1142/s0219633612501064.

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Thermal desorption-comprehensive two-dimensional gas chromatography high-resolution time-of-flight mass spectrometry (TD–GC × GC–HRTOF-MS) is one of the most powerful tools in analytical nanoparticle compounds. Genetic algorithm and partial least square (GA-PLS) and kernel PLS (GA-KPLS) models were used to investigate the correlation between reverse factor (RF) and descriptors for 50 nanoparticles fraction with a diameter of 29–58 nm in roadside atmosphere which obtained by TD–GC×GC–HRTOF-MS. The correlation coefficient leave-group-out cross validation (LGO-CV (Q2)) of prediction for the GA-PLS and GA-KPLS models for training and test sets were (0.761 and 0.718) and (0.825 and 0.814), respectively, revealing the reliability of these models. This is the first research on the quantitative structure-property relationship (QSPR) of the nanoparticles in roadside atmosphere using the GA-PLS and GA-KPLS.

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Elorduy, Iñaki, Nieves Durana, José Antonio García, María Carmen Gómez, and Lucio Alonso. "Evaluation of Uncertainty Associated with Determination of Particle-bound PAHs in Ambient Area by TD-GC/MS and Soxhlet-GC/MS." Aerosol and Air Quality Research 18, no. 5 (2018): 1236–45. http://dx.doi.org/10.4209/aaqr.2017.12.0578.

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van Oort, Pouline M., Paul Brinkman, Gitte Slingers, Gudrun Koppen, Adrie Maas, Joris J. Roelofs, Ronny Schnabel, et al. "Exhaled breath metabolomics reveals a pathogen-specific response in a rat pneumonia model for two human pathogenic bacteria: a proof-of-concept study." American Journal of Physiology-Lung Cellular and Molecular Physiology 316, no. 5 (May 1, 2019): L751—L756. http://dx.doi.org/10.1152/ajplung.00449.2018.

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Volatile organic compounds in breath can reflect host and pathogen metabolism and might be used to diagnose pneumonia. We hypothesized that rats with Streptococcus pneumoniae ( SP) or Pseudomonas aeruginosa ( PA) pneumonia can be discriminated from uninfected controls by thermal desorption-gas chromatography-mass-spectrometry (TD-GC-MS) and selected ion flow tube-mass spectrometry (SIFT-MS) of exhaled breath. Male adult rats ( n = 50) received an intratracheal inoculation of 1) 200 µl saline, or 2) 1 × 107 colony-forming units of SP or 3) 1 × 107 CFU of PA. Twenty-four hours later the rats were anaesthetized, tracheotomized, and mechanically ventilated. Exhaled breath was analyzed via TD-GC-MS and SIFT-MS. Area under the receiver operating characteristic curves (AUROCCs) and correct classification rate (CCRs) were calculated after leave-one-out cross-validation of sparse partial least squares-discriminant analysis. Analysis of GC-MS data showed an AUROCC (95% confidence interval) of 0.85 (0.73–0.96) and CCR of 94.6% for infected versus noninfected animals, AUROCC of 0.98 (0.94–1) and CCR of 99.9% for SP versus PA, 0.92 (0.83–1.00), CCR of 98.1% for SP versus controls and 0.97 (0.92–1.00), and CCR of 99.9% for PA versus controls. For these comparisons the SIFT-MS data showed AUROCCs of 0.54, 0.89, 0.63, and 0.79, respectively. Exhaled breath analysis discriminated between respiratory infection and no infection but with even better accuracy between specific pathogens. Future clinical studies should not only focus on the presence of respiratory infection but also on the discrimination between specific pathogens.

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Diep, Tung Thanh, Michelle Ji Yeon Yoo, Chris Pook, Saeedeh Sadooghy-Saraby, Abhishek Gite, and Elaine Rush. "Volatile Components and Preliminary Antibacterial Activity of Tamarillo (Solanum betaceum Cav.)." Foods 10, no. 9 (September 17, 2021): 2212. http://dx.doi.org/10.3390/foods10092212.

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Tamarillo is a nutrient-dense fruit with a unique aroma from its volatile compounds (VCs). In this study, we aimed to compare the volatile profiles: (i) of fresh and freeze-dried tamarillo; (ii) detected using Thermal Desorption–Gas Chromatography–Mass Spectrometry (TD–GC–MS) and Solid-Phase MicroExtraction–Gas Chromatography-Mass Spectrometry (SPME–GC–MS); (iii) of freeze-dried pulp and peel of New Zealand grown tamarillo. The possible antibacterial activity of freeze-dried tamarillo extracts was also investigated. We show that freeze-drying maintained most of the VCs, with some being more concentrated with the loss of water. The most abundant VC in both fresh and freeze-dried tamarillo was hexanoic acid methyl ester for pulp (30% and 37%, respectively), and (E)-3-Hexen-1-ol for peel (36% and 29%, respectively). With the use of TD–GC–MS, 82 VCs were detected for the first time, when compared to SPME–GC–MS. Methional was the main contributor to the overall aroma in both peel (15.4 ± 4.2 μg/g DW) and pulp (118 ± 8.1 μg/g DW). Compared to water as the control, tamarillo extracts prepared by water and methanol extraction showed significant antibacterial activity against E. coli, P. aeruginosa, and S. aureus with zone of inhibition of at least 13.5 mm. These results suggest that freeze-dried tamarillo has a potential for use as a natural preservative to enhance aroma and shelf life of food products.

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Reichel, Julia, Johanna Graßmann, Thomas Letzel, and Jörg E. Drewes. "Systematic Development of a Simultaneous Determination of Plastic Particle Identity and Adsorbed Organic Compounds by Thermodesorption–Pyrolysis GC/MS (TD-Pyr-GC/MS)." Molecules 25, no. 21 (October 28, 2020): 4985. http://dx.doi.org/10.3390/molecules25214985.

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Micro-, submicro- and nanoplastic particles are increasingly regarded as vectors for trace organic chemicals. In order to determine adsorbed trace organic chemicals on polymers, it has usually been necessary to carry out complex extraction steps. With the help of a newly designed thermal desorption pyrolysis gas chromatography mass spectrometry (TD-Pyr-GC/MS) method, it is possible to identify adsorbed trace organic chemicals on micro-, submicro- and nanoparticles as well as the particle short chain polymers in one analytical setup without any transfers. This ensures a high sample throughput for the qualitative analysis of trace substances and polymer type. Since the measuring time per sample is only 2 h, a high sample throughput is possible. It is one of the few analytical methods which can be used also for the investigation of nanoplastic particles. Initially adsorbed substances are desorbed from the particle by thermal desorption (TD); subsequently, the polymer is fragmented by pyrolysis (PYR). Both particle treatment techniques are directly coupled with the same GC-MS system analyzing desorbed molecules and pyrolysis products, respectively. In this study, we developed a systematic and optimized method for this application. For method development, the trace organic chemicals phenanthrene, α-cypermethrin and triclosan were tested on reference polymers polystyrene (PS), polymethyl methacrylate (PMMA) and polyethylene (PE). Well-defined particle fractions were used, including polystyrene (sub)micro- (41 and 40 µm) and nanoparticles (78 nm) as well as 48-µm sized PE and PMMA particles, respectively. The sorption of phenanthrene (PMMA << PS 40 µm < 41 µm < PE < PS 78 nm) and α-cypermethrin (PS 41 µm < PS 40 µm < PE < PMMA < PS 78 nm) to the particles was strongly polymer-dependent. Triclosan adsorbed only on PE and on the nanoparticles of PS (PE < PS78).

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Zhang, Zhong Feng, Lan Sheng Wang, Qing Zhi Ma, and Wan Xi Peng. "Study on Heat Release Behavior of Pinus Biomass by TD-GC-MS." Applied Mechanics and Materials 55-57 (May 2011): 152–56. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.152.

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Pinus has been put into mass production. However, many heat release volatiles would produce air pollution during drying process. Therefore, the heat release behavior of Pinus biomass was studied by TD-GC/MS. The main constituents were at 100°С 1,4-methanoazulene,decahydro-4,8, 8-trimethyl-9-methylene-(30.6%), 1,4-methanoazulen-9-ol,decahydro-1,5,5,8a-tetramethyl-(14.85%), 1,2,4-methenoazulene, decahydro-1,5,5,8a-tetramethyl-(8.56%), 1r-.alpha.-pinene(7.92%), epiglobulol(4.57%), bicyclo[2.2.1]heptan- 2-one, 1,7,7- trimethyl-, (1r)- (4.33%), caryophyllene oxide(3.37%), etc. And the main constituents at 110°С were 1,4-methanoazulene, decahydro-4,8, 8-trimethyl-9-methylene-(40.31%), 1,4-methanoazulen-9-ol, decahydro-1,5,5,8a-tetramethyl-(15.35%), .alpha.-pinene(8.88%), bicyclo [2.2.1]heptan-2-one, 1,7,7- trimethyl-, (1r)- (5.73%), cyclohexane-1,3-dione, 2-allylamin omethylene-5,5-dimethyl-(5.24%), naphthalene, 1,1'-(1,2-ethanediyl) bis[decahydro-(4.83%), spiro[5.5]undec-2-ene,3,7,7-trime thyl-11-methylene-(4.05%), etc. The heat release volatiles of Pinus biomass was safe to people during drying process.

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Pang, Yan, and Zhong Wei Wang. "Analysis on Biohealth Function of Dried Pinus Biomass by TD-GC-MS." Applied Mechanics and Materials 55-57 (May 2011): 170–74. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.170.

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In order to evaluate its potential health risk to human, the volatiles of the dried Pinus biomass were adsorbed and determined by TD-GC-MS. And the main constituents of volatiles at 210°С were 1,4-methanoazulene, decahydro-4,8, 8-trimethyl-9-methylene-(11.75%), acetic acid (6.38%), 1,4-methanoazulen-3-ol, decahydro-1,5,5,8a-tetramethyl-(5.76%), 1r-.alpha.-pinene (5.18%), 1-phenanthrenecarboxaldehyde, 7-et henyl-1,2,3,4,4a,4b,5,6,7,9,10,10a -dodecahydro- 1,4a,7-trimethyl-(4.78%), 2-furancarboxaldehyde, 5-(hydroxym ethyl)- (4.39%), 2-methyliminoperhydro-1,3-oxazine (3.67%), 1,3-benzodioxole, 5-(2-propenyl)- (3.33%), etc. So the dried Pinus biomass had biohealth function.

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Rai, Sujeet Kumar, Meng-Rui Lee, Chien-Feng Lee, Jye-Luen Lee, Ting-I. Chou, Shih-Wen Chiu, Sheng-Kai Liang, Jen-Chung Ko, and Kea Tiong Tang. "Investigation of Exhaled Breath Biomarkers for LUNG Cancer By TD-GC-MS." ECS Meeting Abstracts MA2020-01, no. 34 (May 1, 2020): 2402. http://dx.doi.org/10.1149/ma2020-01342402mtgabs.

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Tateo, F., and M. Bononi. "Determination of gamma-butyrolactone (GBL) in foods by SBSE-TD/GC/MS." Journal of Food Composition and Analysis 16, no. 6 (December 2003): 721–27. http://dx.doi.org/10.1016/s0889-1575(03)00067-x.

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Carmona, Manuel, Javier Martínez, Amaya Zalacain, Ma Luz Rodríguez-Méndez, José Antonio de Saja, and Gonzalo Luis Alonso. "Analysis of saffron volatile fraction by TD–GC–MS and e-nose." European Food Research and Technology 223, no. 1 (December 28, 2005): 96–101. http://dx.doi.org/10.1007/s00217-005-0144-5.

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Wang, Yacheng, Qimei Liu, Dongfang Zheng, Yong Zhao, Ting Wang, Shuangxi Yan, and Haiping Gu. "Active constituents of Koelreuteria paniculata root." Thermal Science 24, no. 3 Part A (2020): 1737–44. http://dx.doi.org/10.2298/tsci190517046w.

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In this paper, Koelreuteria paniculata roots was taken as the research object, and its active substances were analyzed. First, Koelreuteria paniculata roots was crushed, dried, extracted, filtered, and concentrated by rotary evaporation. Then, the active substances of Koelreuteria paniculata roots were extracted with ethanol, benzene/ethanol, and methanol. Finally, Koelreuter was detected by GC-MS, FT-IR, TD-GC-MS, and TG analyses. Data analysis revealed that Koelreuteria paniculata roots contains oleic acid, linoleic acid, Lupinol, retinal, and other active substances that are of great value to medical, chemical, and food industries.

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Pokryshkin, Sergey, Yuliya Sypalova, Artem Ivahnov, and Aleksandr Kozhevnikov. "Optimization of Approaches to Analysis of Lignin by Thermal Decomposition." Polymers 15, no. 13 (June 28, 2023): 2861. http://dx.doi.org/10.3390/polym15132861.

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The ratio of monomeric units is one of the main characteristics of lignin, which affects the possibilities and strategies for further processing. Pyrolytic and thermal desorption decomposition of lignins followed by mass detection of macromolecule fragments are the most common methods for determining the amount of lignin structural units. Two methods of thermal decomposition of lignin were studied: thermal desorption–GC/MS (TD–GC/MS) and pyrolysis–GC/MS (Py–GC/MS). It was noted that, when using different thermal decomposition modes, the composition of the products changes, which affects the accuracy of determining the amount of lignin structural fragments. This article investigated the influence of the sample weight, the thermal decomposition temperature, and the duration of the process in various modes on the quantitation of the lignin structural units. The optimal process conditions were established. It was shown that the DS–Py–GC/MS with cryofocusing, a sample weight of 0.2–0.4 mg, and heating from 50 to 400 °C at a rate of 120 °C/min are preferable. The HSQC NMR was used as a comparison method to obtain the content of the S/G/H units. The results showed the applicability of the proposed approaches to hardwood lignins close to native.

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Steckel, Vera, Anna Knöpfle, and Martin Ohlmeyer. "Effects of climatic test parameters on acetic acid emission from beech (Fagus sylvatica L.)." Holzforschung 67, no. 1 (January 1, 2013): 47–51. http://dx.doi.org/10.1515/hf-2011-0237.

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Abstract Acetic acid (AA) emission from beech samples was studied in test chambers operated according to ISO 16000 part 9 and as a function of temperature and relative humidity (RH). The impact of RH was higher than that of temperature. AA emission was about 45% higher at 75% RH than under standard parameters (50% RH, 23°C). Probably, RH influences AA emission both by enhanced hydrolysis of acetyl groups, as well as by facilitating the release of AA into the surrounding air by diffusion. The concentration of AA in test chamber air was determined with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) as well as with ion chromatography (IC). Both techniques provided similar results. The values measured by IC ranged constantly 15% below those obtained with TD-GC-MS. This can be ascribed to losses during sampling of test chamber air.

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Liu, Xuan, Zhu-Mei Sun, Yan-Na Liu, Qing Ji, Hua Sui, Li-Hong Zhou, Fu-Feng Li, and Qi Li. "The Metabonomic Studies of Tongue Coating inH. pyloriPositive Chronic Gastritis Patients." Evidence-Based Complementary and Alternative Medicine 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/804085.

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In Traditional Chinese Medicine (TCM), tongue diagnosis (TD) has been an important diagnostic method for the last 3000 years. Tongue coating can be used as a very sensitive marker to determine the progress of chronic gastritis. Therefore, the scientific, qualitative, and quantitative study for the pathophysiologic basis of tongue coating (TC) emerged as a major direction for the objective research of TD. In our current report, we used GC/MS technology to determine the potential changes of metabolites and identify special metabolic biomarkers in the TC ofH. pyloriinfected chronic gastritis patients. Four discriminative metabolites were identified by GC/MS between the TC ofH. pyloriinfection (G+H) and withoutH. pyloriinfection (G-H) patients: ethylene, cephaloridine,γ-aminobutyric acid, and 5-pyroglutamic acid, indicating that changes in amino acid metabolism are possibly involved in the formation of TC, and the amino acid metabolites are part of the material components of TC inG+Hpatients.

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Ma, Qing Zhi, Dang Quan Ma, Lu Yang Xiao, and Qi Mei Liu. "Study on Health Function of Cunninghamia lanceolata Biomass by TD-GC-MS." Materials Science Forum 704-705 (December 2011): 577–80. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.577.

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Cunninghamia lanceolata has been the dominated species of plantation forest in South China. However, the most products made from Cunninghamia lanceolata biomass are lower value added. In order to obtain top value-added products, health function of Cunninghamia lanceolata biomass were studied by TD-GC-MS. Relative content of each component was determined by area normalization. The main 40°С volatiles were 1-propanone, 2-amino-1-phenyl-(14.22%), benzene (11.17%), acetic acid (10.16%), cyclopentanecarboxylic acid, 1-(2-butenyl)-2-oxo-, ethyl ester, (e)-( 7.56%), 1h-cyclopenta [1,3] cyclopropa [1,2] b enzene, octahydro-7-methyl-3-methylene-4-(1-methylethyl)-(6.24%), etc. And the main 60°С volatiles were cedrol (29.65%), acetic acid (12.35%), cyclopentanecarboxylic acid, 1-(2-butenyl)-2-oxo-, ethyl ester, (e)- (7.78%), 1,6-cyclodecadiene, 1-methyl-5-met hylene-8-(1-methylethyl)- (6.11%), etc. So Cunninghamia lanceolata biomass had health function under indoor temperature. Keywords: Health function; Cunninghamia lanceolata; Biomass; TD-GC-MS

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Kaikiti, Chrystalla, Marinos Stylianou, and Agapios Agapiou. "TD-GC/MS analysis of indoor air pollutants (VOCs, PM) in hair salons." Chemosphere 294 (May 2022): 133691. http://dx.doi.org/10.1016/j.chemosphere.2022.133691.

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Zhang, Xu, Qing Zhi Ma, Zhong Feng Zhang, and Wan Xi Peng. "Study on Heat Release Behavior of Smoked Bamboo Biomass by TD-GC-MS." Key Engineering Materials 467-469 (February 2011): 1716–20. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.1716.

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Smoked bamboo has been put into mass production. However, many heat release volatiles would produce air pollution during thermoplasticization process. Therefore, the heat release behavior of smoked bamboo biomass was studied by TD-GC/MS to make full use of and prevent the pollution of the volatile materials. The main constituents were acetic acid(43.95%), cyclotrisiloxane, hexamethyl-(15.89%), octasiloxane, 1,1,3,3,5,5,7,7,9,9, 11,11,13,13,15,15-hexadecamethyl-(8.22%), 1,3-benzodioxole, 5-(2-propenyl)- (4.8%), cyclodecasiloxane, eicosamethyl-(4.51%), etc at 100°С. And the main constituents were acetic acid(42.05%), 1-phenanthrenecarboxaldehyde,7-ethenyl- 1,2,3,4,4a, 4b,5,6,7,9,10,10a-dodecahydro-1,4a,7-trimethyl-(8.42%), bicyclo[2.2.1]heptan-2-one, 1,7,7-trimethyl-,(1r)- (8.12%), cyclotrisiloxane, hexamethyl-(6.17%), 1,3-benzodioxole, 5-(2- propenyl)-(5.26%), 4-nitro-4'-chlorodiphenylsulfoxide(3.13%), etc at 115°С. The heat release volatiles of smoked bamboo biomass might be used as biomedicines. Particularly, the volatiles had good application prospects and popularized value in purification of cedrol and acetic acid.

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Peng, Wan Xi, Qiu Xue, Feng Juan Wu, Xu Zhang, and Zhong Feng Zhang. "Study on Thermal Aging Properties of Engineering Smoked Bamboo by TD-GC-MS." Advanced Materials Research 183-185 (January 2011): 639–43. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.639.

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In order to evaluate its thermal aging properties, the volatile organic compounds of engineering smoked bamboo were adsorbed and determined by TD-GC-MS. The result were: (1) The main constituents of volatiles at 160°С were acetic acid(42.20%), benzofuran, 2,3-dihydro- (7.32%), 1,3-benzodioxole, 5-(2-propenyl)-(5.72%), etc. (2) The main constituents of volatiles at 180°С were acetic acid(41.69%), benzofuran, 2,3-dihydro- (7.32%), 3(5)-[[1,2-dihydroxy-3-propoxy]met hyl]-4-hydroxy- 1h-pyrazole-5(3)-ca rboxamide (6.75%), 1-phenanthrenecarboxaldehyde, 7-ethenyl- 1,2,3,4,4a,4b,5,6,7,9,10,10a- dodecahydro- 1,4a,7 - trimethyl- (3.46%),etc. So the engineering smoked bamboo was safe under 160-180°С.

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Zhang, Zhong Feng, Xian Yan Zhou, and Qing Zhi Ma. "Analysis on Biohealth Function of Black Modified Bamboo Biomass by TD-GC-MS." Advanced Materials Research 183-185 (January 2011): 649–53. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.649.

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Black bamboo, who was considered to have biohealth function in folk, is becoming a major biomass in rooms. Therefore, the chemical components from black bamboo were identified by TD-GC/MS at different temperature. The main components of black bamboo biomass at 300°С were butanal(13.29%) , 3,4-dihydroxyacetophenone (8.80%) , ethene, (2-methoxyethoxy)-( 8.68%), acetic acid, anhydride with formic acid(7.21%) , furfural(6.90%) , 2-cyclopenten-1-one, 2-hydroxy-(6.29%), phenol, 2,6-dimethoxy-(5.67%), etc. And the main components at 320°С were acetic acid(20.87%), benzaldehyde, 2-methyl-(10.96%) , 1,3-propanediamine, n-methyl-(8.72%), phenol, 2,6-dimethoxy-(5.87%), 2-furanmethanol(5.26%), etc. Black bamboo biomass was more healthy to human at 300°С than 320°С. So black bamboo biomass was biohealth function.

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Veillerot, M., A. Danel, S. Cetre, and F. Tardif. "Deposition kinetic of airborne organic contamination on wafers measured by TD-GC/MS." Materials Science and Engineering: B 102, no. 1-3 (September 2003): 385–89. http://dx.doi.org/10.1016/s0921-5107(02)00628-1.

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Moyano, Lourdes, María P. Serratosa, Ana Marquez, and Luis Zea. "Optimization and validation of a DHS-TD-GC-MS method to wineomics studies." Talanta 192 (January 2019): 301–7. http://dx.doi.org/10.1016/j.talanta.2018.09.032.

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Joó, É., J. Dewulf, M. Demarcke, C. Amelynck, N. Schoon, J. F. Müller, M. Šimpraga, K. Steppe, and H. Van Langenhove. "Quantification of interferences in PTR-MS measurements of monoterpene emissions from Fagus sylvatica L. using simultaneous TD-GC-MS measurements." International Journal of Mass Spectrometry 291, no. 1-2 (March 2010): 90–95. http://dx.doi.org/10.1016/j.ijms.2010.01.018.

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Canlı, Oltan, Kartal Çetintürk, and Elmas Eva Öktem Olgun. "Determination of 117 endocrine disruptors (EDCs) in water using SBSE TD–GC-MS/MS under the European Water Framework Directive." Analytical and Bioanalytical Chemistry 412, no. 21 (March 16, 2020): 5169–78. http://dx.doi.org/10.1007/s00216-020-02553-4.

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Ouchi, Yukihiro, Hiroyuki Yanagisawa, and Shigehiko Fujimaki. "Evaluating Phthalate Contaminant Migration Using Thermal Desorption–Gas Chromatography–Mass Spectrometry (TD–GC–MS)." Polymers 11, no. 4 (April 15, 2019): 683. http://dx.doi.org/10.3390/polym11040683.

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This study describes a methodology for evaluating regulatory levels of phthalate contamination. By collecting experimental data on short-term phthalate migration using thermal desorption–gas chromatography–mass spectrometry (TD–GC–MS), the migration of di(2-ethylhexyl) phthalate (DEHP) from polyvinyl chloride (PVC) to polyethylene (PE) was found to be expressed by the Fickian approximation model, which was originally proposed for solid (PVC)/liquid (solvent) migration of phthalates. Consequently, good data correlation was obtained using the Fickian approximation model with a diffusion coefficient of 4.2 × 10−12 cm2/s for solid (PVC)/ solid (PE) migration of DEHP at 25 °C. Results showed that temporary contact with plasticized polymers under a normal, foreseeable condition may not pose an immediate risk of being contaminated by phthalates at regulatory levels. However, as phthalates are small organic molecules designed to be dispersed in a variety of polymers as plasticizers at a high compounding ratio, the risk of migration-related contamination can be high in comparison with other additives, especially under high temperatures. With these considerations in mind, the methodology for examining regulatory levels of phthalate contamination using TD–GC–MS has been successfully demonstrated from the viewpoint of its applicability to solid (PVC)/solid (PE) migration of phthalates.

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S, Vinayak, Gayatri R, Eugene Wilson, Shyamala Rajkumar, K. N. Sunil Kumar, S. Selvarajan, and Kanakavalli K. "Bioactive Constituent Profiling of Poly Herbal Distillate Thiribhaladi Dravagam to Evaluate Its Credible Therapeutic Role in Siddha Clinical Practices." Asian Journal of Pharmaceutical Research and Development 8, no. 1 (February 14, 2020): 67–72. http://dx.doi.org/10.22270/ajprd.v8i1.637.

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Introduction: Hydro distillation in Siddha medicine is the technique of extracting valuable principles from a pre-processed raw drug through the traditional process of distillation under a controlled temperature setting. Thiribhaladi Dravagam (TD) is one of the polyherbal distillate formulation stated in the Tamil medical text specified for phlegmatic affections. The drug was subjected to GC-MS studies to screen its bioactive sketch. Methods: Two sets of raw drug samples from different locations were collected. The raw drugs were purified and pre-processed as per the classical literature and distilled in a traditional apparatus. Two distillate samples (TD 1 & TD 2) were prepared from the set of ingredients and were screened for its constituents. Results: The Gas chromatogram of TD 1 revealed 4 prominent peaks with retention time ranging from 4.84 to 8.27. TD 2 reported 8 prominent peaks with retention time ranging from 3.35 to 7.88. The study testified the presence of active volatile metabolites like aldehydes and oxygenated monoterpenes like citral and borneol, monocyclic alcoholic compounds like terpineol and organic acids like caprylic acid from both the samples. TD 2 reported more pharmacologically valuable lead molecules than TD 1, which may be due to the variation in diversity of the two sets of raw drug samples. Conclusion: The bio constituents of TD was found to be pharmacologically significant from the review of various reputed research works supporting the traditional claim on its role in the respiratory system and for maintaining good health. Through the review of Thiribhaladi Dravagam and its analytical part performed through GC-MS, the medical applications of TD in multiple clinical associations and as a perfect health promoter has been justified for promoting its traditional value.

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Park, Da-Jeong, Joon-Young Ahn, Hye-Jung Shin, and Min-Suk Bae. "Characteristics of PM2.5 Carbonaceous Aerosol using PILS-TOC and GC/MS-TD in Seoul." Journal of Korean Society for Atmospheric Environment 30, no. 5 (October 31, 2014): 461–76. http://dx.doi.org/10.5572/kosae.2014.30.5.461.

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Kim, Ki-Hyun, Jan E. Szulejko, Yong-Hyun Kim, and Min-Hee Lee. "An Exploration on the Suitability of Airborne Carbonyl Compounds Analysis in relation to Differences in Instrumentation (GC-MS versus HPLC-UV) and Standard Phases (Gas versus Liquid)." Scientific World Journal 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/308405.

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The relative performance figure of merits was investigated for the two most common analytical methods employed for carbonyl compounds (CC), for example, between high performance liquid chromatography (HPLC)-UV detector (with 2,4-dinitrophenylhydrazine (DNPH) derivatization) and thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) (without derivatization). To this end, the suitability of each method is assessed by computing the relative recovery (RR) between the gas- and liquid-phase standards containing a suite of CC such as formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA), and valeraldehyde (VA) along with benzene (B) as a recovery reference for the GC method. The results confirm that a TD-GC-MS is advantageous to attain the maximum recovery for the heavier CCs (i.e., with molecular weights (MW) above BA−MW ≥ 74). On the other hand, the HPLC-UV is favorable for the lighter CCs (like FA and AA) with the least bias. Such compound-specific responses for each platform are validated by relative ordering of CCs as a function of response factor (RF), method detection limit (MDL), and recovery pattern. It is thus desirable to understand the advantages and limitations of each method to attain the CC data with the least experimental bias.

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Li, Yiyang, Juntao Chen, Yafeng Yang, Cheng Li, and Wanxi Peng. "Chemical compositions and functions of Chinese fir volatiles." Thermal Science 24, no. 3 Part A (2020): 1853–59. http://dx.doi.org/10.2298/tsci190601073l.

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Chinese fir is an important economic tree species in China. In addition to the application of alive trees and wood, the abundant chemical compositions of Chinese fir as a non-wood resource also have very important position. This study used Chinese fir wood powder as material, analyzing the chemical composition of Chinese fir volatiles by Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TG), pyrolisis-gas chromatography-mass spectrometry (Py-GC-MS), thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Through the analysis of the detected we can know that volatiles main were phenolic (cedrol, alpha-bisabolol and beta-eudesmol), ester (dimethyl phthalate, diisobutyl phthalate and dibutyl phthalate), ketone (hydroxyacetone and benzofuran) and aldehyde (hexanal and nonanal) and so on. This compounds and their derivatives can use at wide medical, biology, cosmetics and textile industry.

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McGregor, Laura, Hannah Calder, and Steve Smith. "17 What’s in the Air We Breathe? Chemical Fingerprinting of Organic Species in Pm2.5 By Td-Gc×Gc-Tof Ms." Annals of Work Exposures and Health 67, Supplement_1 (May 1, 2023): i19. http://dx.doi.org/10.1093/annweh/wxac087.050.

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Abstract The issue of urban air quality has received increased attention in recent years due to increased awareness of the potential health risks associated with particulate matter (PM) concentrations. Airborne particulate matter is composed of solid and/or liquid materials of various sizes, but the fine particles with diameters of <2.5 μm (so-called PM2.5) are of most concern, as long-term exposure to PM2.5 is thought to have the biggest impact on public health. PM2.5 consists of a wide range of components, from both primary emissions (e.g. vehicle exhausts or forest fires) and secondary reactions (i.e. compounds formed in the atmosphere by chemical reactions). It is important to have robust analysis of PM2.5 as the composition can give an indication of its source. PM2.5 is typically trapped onto quartz ﬁbre ﬁlters and the semi-volatile organic compounds (SVOCs) are extracted using a solvent. Direct thermal desorption (TD) of the filter avoids this time-consuming sample preparation, for simple, yet sensitive, analysis of particulate matter. However, their identification and quantitation remains a challenge due to sample complexity. Analysts may attempt to address this using longer columns and/or slower oven temperature ramps, but this inevitably leads to longer analysis times. In recent years, the complexity of such samples has been revealed using the improved separation of comprehensive two-dimensional GC coupled with time-of-flight mass spectrometry (GC×GC–TOF MS). Here, we demonstrate the enhanced performance of a TD-GC×GC–TOF MS through analysis of a number of real-world PM2.5 filters.

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Reichel, Julia, Johanna Graßmann, Oliver Knoop, Thomas Letzel, and Jörg E. Drewes. "A Novel Analytical Approach to Assessing Sorption of Trace Organic Compounds into Micro- and Nanoplastic Particles." Biomolecules 12, no. 7 (July 6, 2022): 953. http://dx.doi.org/10.3390/biom12070953.

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Assessing the sorption of trace organic compounds (TOrCs) into micro- and nanoplastic particles has traditionally been performed using an aqueous phase analysis or solvent extractions from the particle. Using thermal extraction/desorption–gas chromatography/mass spectrometry (TD-Pyr-GC/MS) offers a possibility to analyze the TOrCs directly from the particle without a long sample preparation. In this study, a combination of two analytical methods is demonstrated. First, the aqueous phase is quantified for TOrC concentrations using Gerstel Twister® and TD-GC/MS. Subsequently, the TOrCs on the particles are analyzed. Different polymer types and sizes (polymethyl methacrylate (PMMA), 48 µm; polyethylene (PE), 48 µm; polystyrene (PS), 41 µm; and PS, 78 nm) were analyzed for three selected TOrCs (phenanthrene, triclosan, and α-cypermethrin). The results revealed that, over a period of 48 h, the highest and fastest sorption occurred for PS 78 nm particles. This was confirmed with a theoretical calculation of the particle surface area. It was also shown for the first time that direct quantification of TOrCs from PS 78 nm nanoparticles is possible. Furthermore, in a mixed solute solution, the three selected TOrCs were sorbed onto the particles simultaneously.

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Qualley, Anthony, Geoffrey T. Hughes, and Mitchell H. Rubenstein. "Data quality improvement for field-portable gas chromatography-mass spectrometry through the use of isotopic analogues for in-situ calibration." Environmental Chemistry 17, no. 1 (2020): 28. http://dx.doi.org/10.1071/en19134.

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Environmental contextQuantitative field-based sampling of airborne volatile organics continues to be a challenge because of the absence of laboratory supplies and facilities. Approaches are required to overcome poor data arising from difficulties with calibration of fielded instruments. This method normalises responses across portable thermal desorption gas-chromatography mass spectrometers and requires no advance calibration, enabling accurate and precise use of previously established response factors ported from the laboratory to fielded instruments. AbstractSorbent capture provides a process for collecting airborne volatile organic compounds (VOCs) for analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). Under typical laboratory conditions, analytical standards are readily available and calibration of instrumentation is a routine process. In contrast, field-portable instruments are standardised using a representative curve prepared on a limited number of instruments and then applied to fielded units. The performance of field-portable TD-GC-MS systems when deployed to multiple remote sites was studied, and a large variability in sensitivity and performance was observed when using the manufacturer-prescribed methods for calibration of instruments and normalisation of the data. This variability was remedied by the implementation of a non-interfering calibration that is pre-incorporated onto the sorbent media. Use of an in-situ calibration curve constructed using stable isotope labelled standards provided robust quantification, accuracy of measurement and diagnostic capabilities for malfunctioning fielded equipment. Pre-incorporation of isotopic analogues onto thermal desorption tubes in advance of field distribution greatly improves the accuracy and reproducibility of analyses and demonstrates, for the first time, definitive quantification of target analytes using field-portable GC-MS in an operational theatre.

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Scherer, Nicole, Klaudia Marcseková, Tobias Posset, and Gerhard Winter. "New studies on leachables in commercial scale protein drug filling lines using stir bar sorptive extraction coupled with TD-GC–MS and UPLC/QTOF-MS/MS analytics." International Journal of Pharmaceutics 555 (January 2019): 404–19. http://dx.doi.org/10.1016/j.ijpharm.2018.11.033.

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Wang, Meng, Ru-Jin Huang, Junji Cao, Wenting Dai, Jiamao Zhou, Chunshui Lin, Haiyan Ni, et al. "Determination of n-alkanes, polycyclic aromatic hydrocarbons and hopanes in atmospheric aerosol: evaluation and comparison of thermal desorption GC-MS and solvent extraction GC-MS approaches." Atmospheric Measurement Techniques 12, no. 9 (September 6, 2019): 4779–89. http://dx.doi.org/10.5194/amt-12-4779-2019.

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Abstract. Organic aerosol (OA) constitutes a large fraction of fine particulate matter (PM) in the urban air. However, the chemical nature and sources of OA are not well constrained. Quantitative analysis of OA is essential for understanding the sources and atmospheric evolution of fine PM, which requires accurate quantification of some organic compounds (e.g., markers). In this study, two analytical approaches, i.e., thermal desorption (TD) gas chromatography mass spectrometry (GC-MS) and solvent extract (SE) GC-MS, were evaluated for the determination of n-alkanes, polycyclic aromatic hydrocarbons (PAHs) and hopanes in ambient aerosol. For the SE approach, the recovery obtained is 89.3 %–101.5 %, the limits of detection (LODs) are 0.05–1.1 ng (1.5–33.9 ng m−3), repeatability is 3.5 %–14.5 % and reproducibility is 1.2 %–10.9 %. For the TD approach, the recovery is 57.2 %–109.8 %, the LODs are 0.1–1.9 ng (0.04–0.9 ng m−3), repeatability is 2.1 %–19.4 % and reproducibility is 1.1 %–12.9 %. Ambient aerosol samples were collected from Beijing, Chengdu, Shanghai and Guangzhou during the winter of 2013 and were analyzed by the two methods. After considering the recoveries, the two methods show a good agreement with a high correlation coefficient (R2 > 0.98) and a slope close to unity. The concentrations of n-alkanes, PAHs and hopanes are found to be much higher in Beijing than those in Chengdu, Shanghai and Guangzhou, most likely due to emissions from traffic and/or coal combustion for wintertime heating in Beijing.

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Ma, Qing Zhi, Dang Quan Zhang, Qi Mei Liu, and Wan Xi Peng. "Study on Heat Release Behavior of Cunninghamia lanceolata Biomass by TD-GC-MS." Advanced Materials Research 129-131 (August 2010): 38–41. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.38.

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Cunninghamia lanceolata has been the dominated species of plantation forest in South China. And thermoplasticization can decreases the hydroscopicity to increase the additional value of Cunninghamia lanceolata biomass. However, many heat release volatiles would produce air pollution during thermoplasticization process. Therefore, the heat release behavior of Cunninghamia lanceolata biomass was studied by TD-GC/MS to make full use of and prevent the pollution of the volatile materials. The main constituents were cedrol(34.34%), phenol, 2,4-bis(1,1-dimethylethyl)( 11.49%), acetic acid(6.83%), carbon disulfide(3.1%), etc at 150°С. And the main constituents were acetic acid(20.22%), cedrol(17.20%), 1h-3a,7-methanoazulene, 2,3,4,7,8, 8a-hexahydro-3,6,8,8-tetramethyl-(3.58%), benzofuran, 2,3-dihydro-(3.26%), etc at 180°С. The heat release volatiles of Cunninghamia lanceolata biomass might be used as raw materials of bioenergy, rare biomedicines, and so on. Particularly, the volatiles had good application prospects and popularized value in purification of cedrol and acetic acid.

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Selyanchyn, Roman, Takuma Nozoe, Hidetaka Matsui, Tsuyoshi Kadosawa, and Seung-Woo Lee. "TD-GC-MS Investigation of the VOCs Released from Blood Plasma of Dogs with Cancer." Diagnostics 3, no. 1 (January 16, 2013): 68–83. http://dx.doi.org/10.3390/diagnostics3010068.

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Peng, Wanxi, Lansheng Wang, Qiu Xu, Qingding Wu, and Shilong Xiang. "TD-GC-MS Analysis on Thermal Release Behavior of Poplar Composite Biomaterial Under High Temperature." Journal of Computational and Theoretical Nanoscience 9, no. 9 (September 1, 2012): 1431–33. http://dx.doi.org/10.1166/jctn.2012.2217.

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Journal articles on the topic 'Td-Gc-Ms/ms'

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