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Author | Schelles, W.; de Gendt, S.; Maes, K.; Van Grieken, R. | ||||
Title | The use of a secondary cathode to analyse solid non-conducting samples with direct current glow discharge mass spectrometry: potential and restrictions | Type | A1 Journal article | ||
Year | 1996 | Publication | Fresenius' journal of analytical chemistry | Abbreviated Journal | |
Volume | 355 | Issue | Pages | 858-860 | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | A1996UY97500020 | Publication Date | 2004-03-24 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0937-0633; 1432-1130 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:14654 | Serial | 8718 | ||
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Author | Vanderborght, B.M.; Van Grieken, R.E. | ||||
Title | Water analysis by spark-source mass-spectrometry after preconcentration on activated carbon | Type | A1 Journal article | ||
Year | 1980 | Publication | Talanta : the international journal of pure and applied analytical chemistry | Abbreviated Journal | |
Volume | 27 | Issue | 5 | Pages | 417-422 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | For trace analyses of environmental waters, spark-source mass-spectrometry has been combined with a preconcentration procedure involving chelation of the dissolved trace elements with oxine and subsequent adsorption of the oxinates and naturally occurring organic and colloidal metal species onto activated carbon. The activated carbon is filtered off and ashed at low temperature. The residue is dissolved, an internal standard and pure graphite are added and, after drying, the electrodes are prepared. The photographically recorded mass spectrum is evaluated by a suitable computer routine. The error of the procedure is around 30%. While this preconcentration and analysis procedure is capable of measuring about 40 elements quantitatively, in practice 1025 trace elements are determined simultaneously above the 0.1-μg/l. detection limit, as is illustrated by analyses of drinking water, surface and ground water samples. Although a sophisticated technique, SSMS can be considered for regular panoramic survey analyses. | ||||
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Language | Wos | A1980JR07800006 | Publication Date | 2002-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0039-9140; 1873-3573 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:116557 | Serial | 8746 | ||
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Author | Szalóki, I.; Osán, J.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 2006 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 78 | Issue | 12 | Pages | 4069-4096 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Language | Wos | 000238252600016 | Publication Date | 2006-06-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:58857 | Serial | 8771 | ||
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Author | Szalóki, I.; Osán, J.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 2004 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 76 | Issue | 12 | Pages | 3445-3470 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Language | Wos | 000222011100014 | Publication Date | 2004-06-14 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:46259 | Serial | 8772 | ||
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Author | Szalóki, I.; Török, S.B.; Injuk, J.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 2002 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 74 | Issue | 12 | Pages | 2895-2918 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Language | Wos | 000176253700020 | Publication Date | 2002-07-26 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:39517 | Serial | 8773 | ||
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Author | Szalóki, I.; Török, S.B.; Ro, C.-U.; Injuk, J.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 2000 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 72 | Issue | 12 | Pages | 211-233 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000087661500018 | Publication Date | 2002-07-26 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:27850 | Serial | 8774 | ||
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Author | Török, S.; Labar, J.; Schmeling, M.; Van Grieken, R. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1998 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 70 | Issue | Pages | 495r-517r | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000074161100020 | Publication Date | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:20967 | Serial | 8776 | ||
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Author | Török, S.B.; Labar, J.; Injuk, J.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1996 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | R68 | Issue | Pages | 467-485 | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | |||
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:14650 | Serial | 8777 | ||
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Author | Török, S.B.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1992 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 64r | Issue | Pages | 180-196 | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | A1992HZ51800011 | Publication Date | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:2823 | Serial | 8778 | ||
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Author | Markowicz, A.A.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1990 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 62 | Issue | 12 | Pages | 101r-113r |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2006-11-06 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:116527 | Serial | 8779 | ||
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Author | Markowicz, A.A.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1988 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 60 | Issue | 12 | Pages | 28r-42r |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2005-03-08 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:116525 | Serial | 8780 | ||
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Author | Markowicz, A.A.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1986 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 58 | Issue | 5 | Pages | 279r-294r |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2005-03-08 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:116523 | Serial | 8781 | ||
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Author | Markowicz, A.A.; Van Grieken, R.E. | ||||
Title | X-ray spectrometry | Type | A1 Journal article | ||
Year | 1984 | Publication | Reviews in analytical chemistry | Abbreviated Journal | |
Volume | 56 | Issue | Pages | 241r-250r | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | |||
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Series Volume | Series Issue | Edition | |||
ISSN | 0048-752x | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:116709 | Serial | 8782 | ||
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Author | Alvarez-Martin, A.; Quanico, J.; Scovacricchi, T.; Avranovich Clerici, E.; Baggerman, G.; Janssens, K. | ||||
Title | Chemical mapping of the degradation of geranium lake in paint cross sections by MALDI-MSI | Type | A1 Journal article | ||
Year | 2023 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 95 | Issue | 49 | Pages | 18215-18223 |
Keywords | A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS); Ecosphere | ||||
Abstract | Matrix assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) has become a powerful method to extract spatially resolved chemical information in complex materials. This study provides the first use of MALDI-MSI to define spatial–temporal changes in oil paints. Due to the highly heterogeneous nature of oil paints, the sample preparation had to be optimized to prevent molecules from delocalizing. Here, we present a new protocol for the layer-specific analysis of oil paint cross sections achieving a lateral resolution of 10 μm and without losing ionization efficiency due to topographic effects. The efficacy of this method was investigated in oil paint samples containing a mixture of two historic organic pigments, geranium lake and lead white, a mixture often employed in the work of painter Vincent Van Gogh. This methodology not only allows for spatial visualization of the molecules responsible for the pink hue of the paint but also helps to elucidate the chemical changes behind the discoloration of paintings with this composition. The results demonstrate that this approach provides valuable molecular compositional information about the degradation pathways of pigments in specific paint layers and their interaction with the binding medium and other paint components and with light over time. Since a spatial correlation between molecular species and the visual pattern of the discoloration pattern can be made, we expect that mass spectrometry imaging will become highly relevant in future degradation studies of many more historical pigments and paints. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001142876000001 | Publication Date | 2023-11-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 7.4; 2023 IF: 6.32 | |||
Call Number | UA @ admin @ c:irua:201644 | Serial | 9007 | ||
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Author | Deleu, N.; Hillen, M.; Steenackers, G.; Borms, G.; Janssens, K.; Van der Stighelen, K.; Van der Snickt, G. | ||||
Title | Combined macro X-ray fluorescence (MA-XRF) and pulse phase thermography (PPT) imaging for the technical study of panel paintings | Type | A1 Journal article | ||
Year | 2024 | Publication | Talanta : the international journal of pure and applied analytical chemistry | Abbreviated Journal | |
Volume | 270 | Issue | Pages | 125533-11 | |
Keywords | A1 Journal article; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS) | ||||
Abstract | Museum staff usually relies on a proven combination of X-ray radiography (XRR) and infrared reflectography (IRR) to study paintings in a non-destructive manner. In the last decades, however, the research toolbox of heritage scientists has expanded considerably, with a prime example being macro X-ray fluorescence (MA-XRF), producing element-specific images. The goal of this article is to illustrate the added value of augmenting MA-XRF with pulse phase thermography (PPT), a variant of active infrared thermographic imaging (IRT), which is an innovative diagnostic method that is able to reveal variations between or in materials, based on a different response to minor fluctuations in temperature when irradiated with optical radiation. By examining three 16thand 17th-century panel paintings we assess the extent in which combined MA-XRF and PPT contributes to a better understanding of two commonly encountered interventions to panel paintings: (a) Anstuckungen (enlargement of the panel) or (b) substitutions (replacement of part of the panel). Yielding information from different depths of the painting, these two techniques proved highly complementary with IRR and XRR, expanding the understanding of the build-up, genesis, and material history of the paintings. While MA-XRF documented the interventions to the wooden substrate indirectly by revealing variations in painting materials, paint handling and/ or layer sequence between the original part and the extended or replaced planks, PPT proved beneficial for the study of the wooden support itself, by providing a clear image of the wood structure quasi-free of distortion by the superimposed paint or cradling. XRR, on the other hand, revealed other features from the wood structure, not visible with PPT, and allowed looking through the wooden panels, revealing e.g. the dowels used for joining the planks. Additionally, IRR visualised dissimilarities in the underdrawings. In this way, the results indicate that PPT has the potential to become an acknowledged add-on to the expanding set of imaging methods for paintings, especially when used in combination with MA-XRF, IRR and XRR. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001144098200001 | Publication Date | 2023-12-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0039-9140; 1873-3573 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 6.1 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 6.1; 2024 IF: 4.162 | |||
Call Number | UA @ admin @ c:irua:203764 | Serial | 9193 | ||
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Author | Verlinden, G.; Janssens, G.; Gijbels, R.; van Espen, P.; Geuens, I. | ||||
Title | Three-dimensional chemical characterization of complex silver halide microcrystals by scanning ion microprobe mass analysis | Type | A1 Journal article | ||
Year | 1997 | Publication | Analytical chemistry | Abbreviated Journal | Anal Chem |
Volume | 69 | Issue | Pages | 3773-3779 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3) | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | A1997XV71200019 | Publication Date | 2002-07-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700;1520-6882; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | 6 | Open Access | |
Notes | Approved | Most recent IF: 6.32; 1997 IF: 4.743 | |||
Call Number | UA @ lucian @ c:irua:16959 | Serial | 3647 | ||
Permanent link to this record | |||||
Author | Aghaei, M.; Lindner, H.; Bogaerts, A. | ||||
Title | Ion Clouds in the Inductively Coupled Plasma Torch: A Closer Look through Computations | Type | A1 Journal article | ||
Year | 2016 | Publication | Analytical chemistry | Abbreviated Journal | Anal Chem |
Volume | 88 | Issue | 88 | Pages | 8005-8018 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We have computationally investigated the introduction of copper elemental particles in an inductively coupled plasma torch connected to a sampling cone, including for the first time the ionization of the sample. The sample is inserted as liquid particles, which are followed inside the entire torch, i.e., from the injector inlet up to the ionization and reaching the sampler. The spatial position of the ion clouds inside the torch as well as detailed information on the copper species fluxes at the position of the sampler orifice and the exhausts of the torch are provided. The effect of on- and off-axis injection is studied. We clearly show that the ion clouds of on-axis injected material are located closer to the sampler with less radial diffusion. This guarantees a higher transport efficiency through the sampler cone. Moreover, our model reveals the optimum ranges of applied power and flow rates, which ensure the proper position of ion clouds inside the torch, i.e., close enough to the sampler to increase the fraction that can enter the mass spectrometer and with minimum loss of material toward the exhausts as well as a sufficiently high plasma temperature for efficient ionization. | ||||
Address | Research Group PLASMANT, Chemistry Department, University of Antwerp , Universiteitsplein 1, 2610 Antwerp, Belgium | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000381654800020 | Publication Date | 2016-07-26 |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | 9 | Open Access | |
Notes | The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO), Grant Number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UA. | Approved | Most recent IF: 6.32 | ||
Call Number | PLASMANT @ plasmant @ c:irua:135644 | Serial | 4293 | ||
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Author | Bogaerts, A. | ||||
Title | Modeling plasmas in analytical chemistry—an example of cross-fertilization | Type | A1 Journal article | ||
Year | 2020 | Publication | Analytical And Bioanalytical Chemistry | Abbreviated Journal | Anal Bioanal Chem |
Volume | 412 | Issue | 24 | Pages | 6059-6083 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | This paper gives an overview of the modeling work developed in our group in the last 25 years for various plasmas used in analytical spectrochemistry, i.e., glow discharges (GDs), inductively coupled plasmas (ICPs), and laser ablation (LA) for sample introduction in the ICP and for laser-induced breakdown spectroscopy (LIBS). The modeling approaches are briefly presented, which are different for each case, and some characteristic results are illustrated. These plasmas are used not only in analytical chemistry but also in other applications, and the insights obtained in these other fields were quite helpful for us to develop models for the analytical plasmas. Likewise, there is now a huge interest in plasma–liquid interaction, atmospheric pressure glow discharges (APGDs), and dielectric barrier discharges (DBDs) for environmental, medical, and materials applications of plasmas. The insights obtained in these fields are also very relevant for ambient desorption/ionization sources and for liquid sampling, which are nowadays very popular in analytical chemistry, and they could be very helpful in developing models for these sources as well. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000522701700005 | Publication Date | 2020-03-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1618-2642 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.3 | Times cited | Open Access | ||
Notes | M. Aghaei, Z. Chen, D. Autrique, T. Martens, and P. Heirman are gratefully acknowledged for their valuable efforts in the model developments illustrated in this paper. | Approved | Most recent IF: 4.3; 2020 IF: 3.431 | ||
Call Number | PLASMANT @ plasmant @c:irua:168600 | Serial | 6412 | ||
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Author | Schram, J.; Parrilla, M.; Sleegers, N.; Samyn, N.; Bijvoets, S.M.; Heerschop, M.W.J.; van Nuijs, A.L.N.; De Wael, K. | ||||
Title | Identifying Electrochemical Fingerprints of Ketamine with Voltammetry and Liquid Chromatography–Mass Spectrometry for Its Detection in Seized Samples | Type | A1 Journal article | ||
Year | 2020 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 92 | Issue | 19 | Pages | 13485-13492 |
Keywords | A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre | ||||
Abstract | Herein, a straightforward electrochemical approach for the determination of ketamine in street samples and seizures is presented by employing screen-printed electrodes (SPE). Square wave voltammetry (SWV) is used to study the electrochemical behavior of the illicit drug, thus profiling the different oxidation states of the substance at different pHs. Besides, the oxidation pathway of ketamine on SPE is investigated for the first time with liquid chromatography–high-resolution mass spectrometry. Under the optimized conditions, the calibration curve of ketamine at buffer solution (pH 12) exhibits a sensitivity of 8.2 μA μM–1, a linear relationship between 50 and 2500 μM with excellent reproducibility (RSD = 2.2%, at 500 μM, n = 7), and a limit of detection (LOD) of 11.7 μM. Subsequently, binary mixtures of ketamine with adulterants and illicit drugs are analyzed with SWV to investigate the electrochemical fingerprint. Moreover, the profile overlapping between different substances is addressed by the introduction of an electrode pretreatment and the integration of a tailor-made script for data treatment. Finally, the approach is tested on street samples from forensic seizures. Overall, this system allows for the on-site identification of ketamine by law enforcement agents in an easy-to-use and rapid manner on cargos and seizures, thereby disrupting the distribution channel and avoiding the illicit drug reaching the end-user. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000580426800091 | Publication Date | 2020-10-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | ||
Notes | Universiteit Antwerpen; H2020 Societal Challenges, 833787 ; Fonds Wetenschappelijk Onderzoek, 1S3765817N 1SB8120N ; | Approved | Most recent IF: 7.4; 2020 IF: 6.32 | ||
Call Number | AXES @ axes @c:irua:170523 | Serial | 6435 | ||
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Author | Gorbanev, Y.; Privat-Maldonado, A.; Bogaerts, A. | ||||
Title | Analysis of Short-Lived Reactive Species in Plasma–Air–Water Systems: The Dos and the Do Nots | Type | A1 Journal Article | ||
Year | 2018 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 90 | Issue | 22 | Pages | 13151-13158 |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | This Feature addresses the analysis of the reactive species generated by nonthermal atmospheric pressure plasmas, which are widely employed in industrial and biomedical research, as well as first clinical applications. We summarize the progress in detection of plasma-generated short-lived reactive oxygen and nitrogen species in aqueous solutions, discuss the potential and limitations of various analytical methods in plasma−liquid systems, and provide an outlook on the possible future research goals in development of short-lived reactive species analysis methods for a general nonspecialist audience. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000451246100002 | Publication Date | 2018-11-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | 17 | Open Access | Not_Open_Access |
Notes | European Commission, 743151 ; This work was supported by the European Marie Sklodowska- Curie Individual Fellowship within Horizon2020 (“LTPAM”, Grant No. 743151). | Approved | Most recent IF: 6.32 | ||
Call Number | PLASMANT @ plasmant @c:irua:156301 | Serial | 5152 | ||
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Author | Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. | ||||
Title | Electrochemistry of intact versus degraded cephalosporin antibiotics facilitated by LC–MS analysis | Type | A1 Journal article | ||
Year | 2021 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 93 | Issue | 4 | Pages | 2394-2402 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre | ||||
Abstract | The electrochemical detection of cephalosporins is a promising approach for the monitoring of cephalosporin levels in process waters. However, this class of antibiotics, like penicillins, is composed of chemically active molecules and susceptible to hydrolysis and aminolysis of the four membered β-lactam ring present. In order to develop a smart monitoring strategy for cephalosporins, the influence of degradation (hydrolysis and aminolysis) on the electrochemical fingerprint has to be taken into account. Therefore, an investigation was carried out to understand the changes of the voltammetric fingerprints upon acidic and alkaline degradation. Changes in fingerprints were correlated to the degradation pathways through the combination of square wave voltammetry and liquid chromatography quadrupole time-of-flight analysis. The characteristic electrochemical signals of the β-lactam ring disappeared upon hydrolysis. Additional oxidation signals that appeared after degradation were elucidated and linked to different degradation products, and therefore, enrich the voltammetric fingerprints with information of the state of the cephalosporins. The applicability of the electrochemical monitoring system was explored by the analysis of the intact and degraded industrial process waters containing the key intermediate 7-aminodeacetoxycephalosporanic acid (7-ADCA). Clearly, the intact process samples exhibited the expected core signals of 7-ADCA and could be quantified, while the degraded samples only showed the newly formed degradation products. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000618089100063 | Publication Date | 2021-01-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 6.32 | |||
Call Number | UA @ admin @ c:irua:176206 | Serial | 7864 | ||
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Author | Dillen, A.; Vandezande, W.; Daems, D.; Lammertyn, J. | ||||
Title | Unraveling the effect of the aptamer complementary element on the performance of duplexed aptamers : a thermodynamic study | Type | A1 Journal article | ||
Year | 2021 | Publication | Analytical And Bioanalytical Chemistry | Abbreviated Journal | Anal Bioanal Chem |
Volume | 413 | Issue | 19 | Pages | 4739-4750 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Duplexed aptamers (DAs) are widespread aptasensor formats that simultaneously recognize and signal the concentration of target molecules. They are composed of an aptamer and aptamer complementary element (ACE) which consists of a short oligonucleotide that partially inhibits the aptamer sequence. Although the design principles to engineer DAs are straightforward, the tailored development of DAs for a particular target is currently based on trial and error due to limited knowledge of how the ACE sequence affects the final performance of DA biosensors. Therefore, we have established a thermodynamic model describing the influence of the ACE on the performance of DAs applied in equilibrium assays and demonstrated that this relationship can be described by the binding strength between the aptamer and ACE. To validate our theoretical findings, the model was applied to the 29-mer anti-thrombin aptamer as a case study, and an experimental relation between the aptamer-ACE binding strength and performance of DAs was established. The obtained results indicated that our proposed model could accurately describe the effect of the ACE sequence on the performance of the established DAs for thrombin detection, applied for equilibrium assays. Furthermore, to characterize the binding strength between the aptamer and ACEs evaluated in this work, a set of fitting equations was derived which enables thermodynamic characterization of DNA-based interactions through thermal denaturation experiments, thereby overcoming the limitations of current predictive software and chemical denaturation experiments. Altogether, this work encourages the development, characterization, and use of DAs in the field of biosensing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000659366300001 | Publication Date | 2021-06-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1618-2642; 1618-2650 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.431 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 3.431 | |||
Call Number | UA @ admin @ c:irua:179163 | Serial | 8713 | ||
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Author | Drăgan, A.-M.; Parrilla, M.; Sleegers, N.; Slosse, A.; Van Durme, F.; van Nuijs, A.; Oprean, R.; Cristea, C.; De Wael, K. | ||||
Title | Investigating the electrochemical profile of methamphetamine to enable fast on-site detection in forensic analysis | Type | A1 Journal article | ||
Year | 2023 | Publication | Talanta : the international journal of pure and applied analytical chemistry | Abbreviated Journal | |
Volume | 255 | Issue | Pages | 124208-124211 | |
Keywords | A1 Journal article; Toxicological Centre; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) | ||||
Abstract | Methamphetamine (MA) is a synthetic psychoactive drug which is consumed both licitly and illicitly. In some countries it is prescribed for attention-deficit and hyperactivity disorder, and short-term treatment of obesity. More often though, it is abused for its psychostimulant properties. Unfortunately, the spread and abuse of this synthetic drug have increased globally, being reported as the most widely consumed synthetic psychoactive drug in the world in 2019. Attempting to overcome the shortcomings of the currently used on-site methods for MA detection in suspected cargos, the present study explores the potential of electrochemical identification of MA by means of square wave voltammetry on disposable graphite screen-printed electrodes. Hence, the analytical characterization of the method was evaluated under optimal conditions exhibiting a linear range between 50 mu M and 2.5 mM MA, a LOD of 16.7 mu M, a LOQ of 50.0 mu M and a sensitivity of 5.3 mu A mM-1. Interestingly, two zones in the potential window were identified for the detection of MA, depending on its concentration in solution. Furthermore, the oxidative pathway of MA was elucidated employing liquid chromatography – mass spectrometry to understand the change in the electrochemical profile. Thereafter, the selectivity of the method towards MA in mixtures with other drugs of abuse as well as common adulterants/cutting agents was evaluated. Finally, the described method was employed for the analysis of MA in confiscated samples and compared with forensic methods, displaying its potential as a fast and easy-to-use method for on-site analysis. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000925076200001 | Publication Date | 2023-01-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0039-9140; 1873-3573 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.1 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 6.1; 2023 IF: 4.162 | |||
Call Number | UA @ admin @ c:irua:194314 | Serial | 8890 | ||
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Author | Steijlen, A.S.M.; Parrilla, M.; Van Echelpoel, R.; De Wael, K. | ||||
Title | Dual microfluidic sensor system for enriched electrochemical profiling and identification of illicit drugs on-site | Type | A1 Journal article | ||
Year | 2024 | Publication | Analytical chemistry | Abbreviated Journal | |
Volume | 96 | Issue | 1 | Pages | 590-598 |
Keywords | A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) | ||||
Abstract | Electrochemical sensors have emerged as a new analytical tool for illicit drug detection to facilitate ultrafast and accurate identification of suspicious compounds on-site. Drugs of abuse can be identified using their unique voltammetric fingerprint at a given pH. Today, the right buffer solution is manually selected based on drug appearance, and in some cases, a consecutive analysis in two different pH solutions is required. In this work, we present a disposable microfluidic multichannel sensor system that automatically records fingerprints in two pH solutions (e.g., pH 5 and pH 12). This system has two advantages. It will overcome the manual selection of a buffer solution at the right pH, decrease analysis time, and minimize the risk of human errors. Second, the combination of two fingerprints, the superfingerprint, contains more detailed information about the samples, which enhances the selectivity of the analytical technique. First, real-time pH measurements proved that the sample can be brought to the desired pH within a minute. Subsequently, an electrochemical study on the microfluidic platform with 1 mM illicit drug standards of MDMA, cocaine, heroin, and methamphetamine showed that the characteristic voltammetric fingerprints and peak potentials are reproducible, also in the presence of common cutting agents. Finally, the microfluidic concept was validated with real confiscated samples, showing promising results for the user-friendly identification of drugs of abuse. In short, this paper presents a successful proof-of-concept study of a multichannel microfluidic sensor system to enrich the fingerprints of illicit drugs at pH 5 and pH 12, thus providing a low-cost, portable, and rapid identification system of illicit drugs with minimal user intervention. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001139443500001 | Publication Date | 2023-12-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 7.4; 2024 IF: 6.32 | |||
Call Number | UA @ admin @ c:irua:201877 | Serial | 9024 | ||
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Author | Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. | ||||
Title | Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings | Type | A1 Journal article | ||
Year | 2017 | Publication | Analytical chemistry | Abbreviated Journal | Anal Chem |
Volume | 89 | Issue | 89 | Pages | 3326-3334 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken. | ||||
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Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000397478300015 | Publication Date | 2017-02-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | 7 | Open Access | OpenAccess |
Notes | ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; | Approved | Most recent IF: 6.32 | ||
Call Number | UA @ lucian @ c:irua:140886 | Serial | 4451 | ||
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Author | Fuchs, J.; Aghaei, M.; Schachel, T.D.; Sperling, M.; Bogaerts, A.; Karst, U. | ||||
Title | Impact of the Particle Diameter on Ion Cloud Formation from Gold Nanoparticles in ICPMS | Type | A1 Journal article | ||
Year | 2018 | Publication | Analytical chemistry | Abbreviated Journal | Anal Chem |
Volume | 90 | Issue | 17 | Pages | 10271-10278 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The unique capabilities of microsecond dwell time (DT) single-particle inductively coupled plasma mass spectrometry (spICPMS) were utilized to characterize the cloud of ions generated from the introduction of suspensions of gold nanoparticles (AuNPs) into the plasma. A set of narrowly distributed particles with diameters ranging from 15.4 to 100.1 nm was synthesized and characterized according to established protocols. Statistically significant numbers of the short transient spICPMS events were evaluated by using 50 μs DT for their summed intensity, maximum intensity, and duration, of which all three were found to depend on the particle diameter. The summed intensity increases from 10 to 1661 counts and the maximum intensity from 6 to 309 counts for AuNPs with diameters from 15.4 to 83.2 nm. The event duration rises from 322 to 1007 μs upon increasing AuNP diameter. These numbers represent a comprehensive set of key data points of the ion clouds generated in ICPMS from AuNPs. The extension of event duration is of high interest to appoint the maximum possible particle number concentration at which separation of consecutive events in spICPMS can still be achieved. Moreover, the combined evaluation of all above-mentioned ion cloud characteristics can explain the regularly observed prolonged single-particle events. The transport and ionization behavior of AuNPs in the ICP was also computationally modeled to gain insight into the size-dependent signal generation. The simulated data reveals that the plasma temperature, and therefore the point of ionization of the particles, is the same for all diameters. However, the maximum number density of Au+, as well as the extent of the ion cloud, depends on the particle diameter, in agreement with the experimental data, and it provides an adequate explanation for the observed ion cloud characteristics. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000444060600028 | Publication Date | 2018-09-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | 5 | Open Access | OpenAccess |
Notes | We thank Dr. Harald Rösner from the Institute of Materials Physics of the University of Münster for the TEM imaging. | Approved | Most recent IF: 6.32 | ||
Call Number | PLASMANT @ plasmant @c:irua:153651 | Serial | 5057 | ||
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Author | Poma, G.; McGrath, T.J.; Christia, C.; Govindan, M.; Covaci, A. | ||||
Title | Emerging halogenated flame retardants in the indoor environment | Type | A1 Journal article | ||
Year | 2020 | Publication | Comprehensive analytical chemistry | Abbreviated Journal | |
Volume | 88 | Issue | Pages | 107-140 | |
Keywords | A1 Journal article; Pharmacology. Therapy; Electron microscopy for materials research (EMAT); Toxicological Centre | ||||
Abstract | Indoor environments are considered an important contributor to external human exposure to halogenated flame retardants (HFRs) due to the large amounts of chemicals currently incorporated in indoor equipment and the time humans spend every day in indoor environments. In this chapter, the presence and use of novel brominated flame retardants (NBFRs), dechlorane plus (DPs), chlorinated organophosphorus flame retardants (Cl-PFRs) and chlorinated paraffins (CPs) in indoor dust, air and consumer products collected from different indoor microenvironments (homes, public indoor spaces, and vehicles) are discussed. While data on the concentrations of HFRs in indoor dust and air are widely available, figures are still scarce for consumer products, such as textiles and foams, furnishings, flooring, electric and electronic products and building materials. This knowledge gaps still represents the biggest obstacle in linking eventual sources of contamination to the presence and chemical patterns in indoor dust and air. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2019-11-22 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 978-0-444-64339-1 | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | OpenAccess | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:168776 | Serial | 6505 | ||
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Author | Aghaei, M.; Bogaerts, A. | ||||
Title | Flowing Atmospheric Pressure Afterglow for Ambient Ionization: Reaction Pathways Revealed by Modeling | Type | A1 Journal article | ||
Year | 2021 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 93 | Issue | 17 | Pages | 6620-6628 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We describe the plasma chemistry in a helium flowing atmospheric pressure afterglow (FAPA) used for analytical spectrometry, by means of a quasione-dimensional (1D) plasma chemical kinetics model. We study the effect of typical impurities present in the feed gas, as well as the afterglow in ambient humid air. The model provides the species density profiles in the discharge and afterglow regions and the chemical pathways. We demonstrate that H, N, and O atoms are formed in the discharge region, while the dominant reactive neutral species in the afterglow are O3 and NO. He* and He2* are responsible for Penning ionization of O2, N2, H2O, H2, and N, and especially O and H atoms. Besides, He2+ also contributes to ionization of N2, O2, H2O, and O through charge transfer reactions. From the pool of ions created in the discharge, NO+ and (H2O)3H+ are the dominant ions in the afterglow. Moreover, negatively charged clusters, such as NO3H2O− and NO2H2O−, are formed and their pathway is discussed as well. Our model predictions are in line with earlier observations in the literature about the important reagent ions and provide a comprehensive overview of the underlying pathways. The model explains in detail why helium provides a high analytical sensitivity because of high reagent ion formation by both Penning ionization and charge transfer. Such insights are very valuable for improving the analytical performance of this (and other) ambient desorption/ionization source(s). | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000648505900008 | Publication Date | 2021-05-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | Open Access | OpenAccess | |
Notes | Fonds Wetenschappelijk Onderzoek, 6713 ; The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO) grant number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the UA. The authors also thank J. T. Shelley for providing experimental data for the gas velocity behind the anode disk and before the mass spectrometer interface, to validate our model. | Approved | Most recent IF: 6.32 | ||
Call Number | PLASMANT @ plasmant @c:irua:178126 | Serial | 6762 | ||
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Author | Neven, L.; Barich, H.; Ching, H.Y.V.; Khan, S.U.; Colomier, C.; Patel, H.H.; Gorun, S.M.; Verbruggen, S.; Van Doorslaer, S.; De Wael, K. | ||||
Title | Correlation between the fluorination degree of perfluorinated zinc phthalocyanines, their singlet oxygen generation ability, and their photoelectrochemical response for phenol sensing | Type | A1 Journal article | ||
Year | 2022 | Publication | Analytical chemistry | Abbreviated Journal | Anal Chem |
Volume | 94 | Issue | 13 | Pages | 5221-5230 |
Keywords | A1 Journal article; Organic synthesis (ORSY); Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) | ||||
Abstract | Electron-withdrawing perfluoroalkyl peripheral groups grafted on phthalocyanine (Pc) macrocycles improve their single-site isolation, solubility, and resistance to self-oxidation, all beneficial features for catalytic applications. A high degree of fluorination also enhances the reducibility of Pcs and could alter their singlet oxygen (1O2) photoproduction. The ethanol/toluene 20:80 vol % solvent mixture was found to dissolve perfluorinated FnPcZn complexes, n = 16, 52, and 64, and minimize the aggregation of the sterically unencumbered F16PcZn. The 1O2 production ability of FnPcZn complexes was examined using 9,10-dimethylanthracene (DMA) and 2,2,6,6-tetramethylpiperidine (TEMP) in combination with UV–vis and electron paramagnetic resonance (EPR) spectroscopy, respectively. While the photoreduction of F52PcZn and F64PcZn in the presence of redox-active TEMP lowered 1O2 production, DMA was a suitable 1O2 trap for ranking the complexes. The solution reactivity was complemented by solid-state studies via the construction of photoelectrochemical sensors based on TiO2-supported FnPcZn, FnPcZn|TiO2. Phenol photo-oxidation by 1O2, followed by its electrochemical reduction, defines a redox cycle, the 1O2 production having been found to depend on the value of n and structural features of the supported complexes. Consistent with solution studies, F52PcZn was found to be the most efficient 1O2 generator. The insights on reactivity testing and structural–activity relationships obtained may be useful for designing efficient and robust sensors and for other 1O2-related applications of FnPcZn. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000786254500002 | Publication Date | 2022-03-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 7.4 | |||
Call Number | UA @ admin @ c:irua:187522 | Serial | 7141 | ||
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Author | Girard-Sahun, F.; Lefrancois, P.; Badets, V.; Arbault, S.; Clement, F. | ||||
Title | Direct sensing of superoxide and its relatives reactive oxygen and nitrogen species in phosphate buffers during cold atmospheric plasmas exposures | Type | A1 Journal article | ||
Year | 2022 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 94 | Issue | 14 | Pages | 5555-5565 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | This study aims at sensing in situ reactive oxygen and nitrogen species (RONS) and specifically superoxide anion (O-2(center dot-)) in aqueous buffer solutions exposed to cold atmospheric plasmas (CAPs). CAPs were generated by ionizing He gas shielded with variable N-2/O-2 mixtures. Thanks to ultramicroelectrodes protected against the high electric fields transported by the ionization waves of CAPs, the production of superoxide and several RONS was electrochemically directly detected in liquids during their plasma exposure. Complementarily, optical emissive spectroscopy (OES) was used to study the plasma phase composition and its correlation with the chemistry in the exposed liquid. The specific production of O-2(center dot-), a biologically reactive redox species, was analyzed by cyclic voltammetry (CV), in both alkaline (pH 11), where the species is fairly stable, and physiological (pH 7.4) conditions, where it is unstable. To understand its generation with respect to the plasma chemistry, we varied the shielding gas composition of CAPs to directly impact on the RONS composition at the plasma-liquid interface. We observed that the production and accumulation of RONS in liquids, including O(2)(center dot-)depends on the plasma composition, with N-2-based shieldings providing the highest superoxide concentrations (few 10s of micromolar at most) and of its derivatives (hundreds of micromolar). In situ spectroscopic and electrochemical analyses provide a high resolution kinetic and quantitative understanding of the interactions between CAPs and physiological solutions for biomedical applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000805334400013 | Publication Date | 2022-03-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 7.4 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 7.4 | |||
Call Number | UA @ admin @ c:irua:189093 | Serial | 7143 | ||
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