Thermogravimetry coupled to an atmospheric pressure photo ionization quadrupole mass spectrometry for the product control of pharmaceutical formulations and the analysis of plasticizers in polymers

Brecht, Dominik; Uteschil, Florian; Schmitz, Oliver J.

doi:10.1016/j.talanta.2019.01.118

Cited by 12 publications

(7 citation statements)

References 45 publications

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“…PDMS was used as sorption material for TFME and two commercial PDMS films were tested using our developed TG-APPI-qMS system [20]. One PDMS film was purchased from Goodfellow GmbH (manufacturer A, Hamburg, Germany) with a film thickness of 0.45 mm (± 10%).…”

Section: Thin-film Microextractionmentioning

confidence: 99%

“…The atmospheric pressure interface lenses (AP1 and AP2) were set to 40 and 20 V, respectively. The scan range was set to 50-700 Da and the dwell time to 2000 ms. A detailed description of the instrumental coupling of the thermogravimetry and the atmospheric pressure photo ionization quadrupole mass spectrometer (TG-APPI-qMS) is described in the literature [20]. To verify the ionization of cyclic siloxanes with atmospheric pressure ionization (APPI), D4-D6 standards were analysed.…”

Section: Tg-appi-qmsmentioning

confidence: 99%

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Analysis of volatile metabolites from in vitro biofilms of Pseudomonas aeruginosa with thin-film microextraction by thermal desorption gas chromatography-mass spectrometry

et al. 2020

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Cystic fibrosis (CF) is an autosomal recessive inherited disease which leads to a production of thickened mucus in the airways. These conditions are conducive to poly-microbial infections, like chronic lung infection, in which Pseudomonas aeruginosa (P. aeruginosa) is the major pathogenic bacterium colonizing CF lungs at the end of the lifetime of CF patients. This in vitro study uses a P. aeruginosa biofilm model under partly cystic fibrosis conditions, with a sampling of volatile extracellular metabolites. The gas sampling was done with thin-film microextraction (TFME) and commercial polydimethylsiloxane (PDMS) films, whereas the analysis of loaded films was done by gas chromatography coupled to quadrupole mass spectrometry and thermodesorption (TD-GC-qMS). For this purpose, two commercially available films were characterized by means of thermogravimetry coupled to a qMS with atmospheric pressure photo ionization (TG-APPI-qMS), regarding homogeneity and temperature stability. The selected film was cleaned using a method developed in this study. The TD-GC-qMS method was successfully used for standards of volatile metabolites which were known to be produced by P. aeruginosa. Limits of detection and quantification of the method for middle and less polar compounds in low nanomolar range (0.5 nM and 1.5 nM) were achieved. The developed method was finally applied to investigate the extracellular volatile metabolites produced by biofilms of the strain P. aeruginosa DSM 50071 under aerobic and anaerobic conditions. In sum, eleven metabolites could be found under both conditions. Furthermore, it was shown in this study that different oxygen conditions (aerobic and anaerobic) resulted in emitting different extracellular volatile metabolites. Specific metabolites, like 1-undecene (aerobic) and 2-undecanone (anaerobic), could be identified. The results are promising, in that the biofilm model may be applicable for the identification of P. aeruginosa under clinical conditions. Furthermore, the model could be the basis for studying extracellular volatile metabolites from different mono-or co-cultures of various bacteria, as well as the implementation of pulmonary conditions, like these in CF lungs. This possibility allows the development of a non-invasive "at-bedside" breath analysis method for CF patients in focus of various bacterial infections.

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Section: Thin-film Microextractionmentioning

confidence: 99%

Section: Tg-appi-qmsmentioning

confidence: 99%

Analysis of volatile metabolites from in vitro biofilms of Pseudomonas aeruginosa with thin-film microextraction by thermal desorption gas chromatography-mass spectrometry

et al. 2020

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“…29,30 The second mass spectrometric hyphenation is composed of a thermobalance (TG 209, Netzsch Geraẗebau, Selb, Germany) coupled to a modified Bruker GC-APCI II source equipped with atmospheric pressure photoionization (APPI) by a Kr vacuum ultraviolet lamp (10/10.6 eV, 124/117 nm) as a soft ionization technique preserving the molecular pattern. 31 The temperature program of the thermobalance with a constant flow of 200 mL/min nitrogen was 2 min isothermal at 20 °C, ramp to 600 °C with 10 K/min, and hold for 10 min at 600 °C. The evolved mixture was sampled via a 300 °C interface and 280 °C transfer line (deactivated fused silica capillary, 0.53 mm inner diameter, 300 °C) into the ion source of the mass spectrometer.…”

Section: ■ Introductionmentioning

confidence: 99%

Comprehensive Chemical Description of Pyrolysis Chars from Low-Density Polyethylene by Thermal Analysis Hyphenated to Different Mass Spectrometric Approaches

et al. 2021

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In the last decades the production and demand of plastics has drastically increased, with severe environmental impact. Concerning climate change and the idea of a circular economy, waste incineration is not favored, and efficient recycling strategies are needed. As one of the most promising approaches, pyrolysis generates a certain amount of solid residue besides liquid and gaseous products.The chemical nature of this coke is not fully understood, but it holds the potential to be used in material science or to generate further chemicals. To explore the value of this feedstock, thermal analysis with mass spectrometric detection of the evolved gas mixture is deployed. With the help of soft photoionization techniques, we were able to identify alkenes, dienes, and polycyclic aromatic hydrocarbons (PAHs), which were emitted at four distinct mass loss events. Here, resonance-enhanced multiphoton ionization allows selectively addressing the aromatic constituents, whereas single-photon ionization covered a comprehensive chemical range. Interestingly, we found an enrichment of UVstabilizers, such as benzophenone, within the macromolecular nature of the residue. The evolved gas mixture was found to be highly complex. Consequently, high-resolution mass spectrometry addressing the isobaric complexity and pyrolysis gas chromatography was used for structural elucidation. We hypothesize island-and archipelago-type structural motives comparable to asphaltenes but with almost no heteroatoms based on analyzing the complex mixture by carbon number versus double bond equivalent cartographies. A comprehensive set of thermal analysis mass spectrometric platforms enabled an in-depth chemical description of plastic pyrolysis coke, valuable knowledge in reactor design and material science.

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“…These photons are thus able to ionize all organic compounds with an ionization energy less than 10 eV. [12][13][14][15][16][17] Another irradiation technique is atmospheric pressure laser ionization (APLI) which utilizes a laser with approximately 5 eV photon energy instead of the VUV lamp in APPI. 18 Penning ionization is also sometimes involved in various ionization techniques, but ESI and APCI are the most important and most common ionization mechanisms of all commercially available ion sources in an atmospheric pressure environment.…”

Section: Introductionmentioning

confidence: 99%

Development of a fast‐switching dual (ESI/APCI) ionization source for liquid chromatography/mass spectrometry

Brecht

Uteschil

Schmitz

2020

Rapid Comm Mass Spectrometry

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High-throughput liquid chromatography/mass spectrometry (LC/MS) is an increasing topic in analytical chemistry. Especially the idle time of a mass spectrometer should be reduced for an efficient and cost-saving use. Therefore, a fast-switching dual ion source was developed, which uses the most important ionization techniques at atmospheric pressure, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), with one or more LC systems. Methods:The performance of the developed ion source is shown by infusion experiments and chromatographic analyses of different standard substances. A highthroughput method is demonstrated by coupling two UHPLC systems to the dual ion source with a triple quadrupole mass spectrometer. Results:No decrease in the ion abundance and a stable performance of the mass spectrometer are presented while using the dual ion source. Instrumental limits of detection are 30 ng L −1 for testosterone using ESI and 1 μg L −1 for vitamin D 3 using APCI. A fast switching between two UHPLC systems and the dual ion source leads to a high sample throughput of 50 samples in 75 min with relative standard deviations for testosterone and vitamin D 3 of 1.5% and 3.8%, respectively.Conclusions: This work presents the development of a dual ESI and APCI ion source operating simultaneously or in switched mode. The results show sensitive and reliable performance as well as the hyphenation to one or more HPLC systems.

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Thermogravimetry coupled to an atmospheric pressure photo ionization quadrupole mass spectrometry for the product control of pharmaceutical formulations and the analysis of plasticizers in polymers

Cited by 12 publications

References 45 publications

Analysis of volatile metabolites from in vitro biofilms of Pseudomonas aeruginosa with thin-film microextraction by thermal desorption gas chromatography-mass spectrometry

Analysis of volatile metabolites from in vitro biofilms of Pseudomonas aeruginosa with thin-film microextraction by thermal desorption gas chromatography-mass spectrometry

Comprehensive Chemical Description of Pyrolysis Chars from Low-Density Polyethylene by Thermal Analysis Hyphenated to Different Mass Spectrometric Approaches

Development of a fast‐switching dual (ESI/APCI) ionization source for liquid chromatography/mass spectrometry

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