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Author | Janssens, K.; Vincze, L.; Vekemans, B.; Williams, C.T.; Radtke, M.; Haller, M.; Knöchel, A. | ||||
Title | The non-destructive determination of REE in fossilized bone using synchrotron radiation induced K-line X-ray microfluorescence analysis | Type | A1 Journal article | ||
Year | 1999 | Publication | Fresenius' journal of analytical chemistry | Abbreviated Journal | |
Volume | 363 | Issue | 4 | Pages | 413-420 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | The sensitivity and applicability of the synchrotron radiation induced X-ray microfluorescence (mu-SRXRF) spectrometer at the Hamburg synchrotron laboratory Hasylab for the determination of the distribution of trace concentrations of rare-earth elements (REE) in fossilized bone are discussed and critically compared to those of other trace analytical methods such as instrumental neutron activation analysis (INAA) and LAMP-ICPMS (laser ablation microprobe inductively-coupled plasma mass spectrometry). Measurements were carried out on two bone samples from contrasting terrestrial depositional environments at Olduvai Gorge (Tanzania). Results indicate that the microdistribution of the REE in these biological materials is not homogeneous and that the relative abundance of these elements can provide information on the palaeoenvironment during the fossilization process. The heterogeneous distribution of the REE can be determined in a quantitative and completely non-destructive manner provided the concentrations of individual REE are above 10 mu g/g. | ||||
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Language | Wos | 000078895300015 | Publication Date | 2002-08-25 | |
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ISSN | 0937-0633 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:103505 | Serial | 5747 | ||
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Author | Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K. | ||||
Title | Stable carbon isotopic ratio measurement of polycyclic aromatic hydrocarbons as a tool for source identification and apportionment : a review of analytical methodologies | Type | A1 Journal article | ||
Year | 2013 | Publication | Talanta : the international journal of pure and applied analytical chemistry | Abbreviated Journal | Talanta |
Volume | 105 | Issue | Pages | 435-450 | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | The measurement of the ratio of stable isotopes of carbon (13C/12C expressed as a δ13C) in the individual components of a sample may be used as a means to identify the origin of these components. This article reviews the approaches and reports on the successes and failures of source identification and apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) with the use of compound-specific isotope analysis (CSIA). One of the conditions for a precise and accurate analysis of isotope ratios with the use of GC-C-IRMS is the need for well separated peaks, with no co-elutions, and reduced unresolved complex mixture (UCM). Additionally, special care needs to be taken for an investigation of possible isotope fractionation effects introduced during the analytical treatment of samples. With the above-mentioned problems in mind, this review discusses in detail and compares current laboratory methodologies, mainly in the extraction and subsequent clean-up techniques used for environmental samples (air particulate matter, soil and sediments). Sampling strategies, the use of isotopic internal standards and the ranges for precision and accuracy are also reported and discussed. | ||||
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Language | Wos | 000319088500064 | Publication Date | 2012-10-30 | |
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ISSN | 0039-9140; 1873-3573 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.162 | Times cited | 19 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 4.162; 2013 IF: 3.511 | ||
Call Number | UA @ admin @ c:irua:102091 | Serial | 5845 | ||
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Author | Anaf, W.; Horemans, B.; Van Grieken, R.; De Wael, K. | ||||
Title | Chemical boundary conditions for the classification of aerosol particles using computer controlled electron probe microanalysis | Type | A1 Journal article | ||
Year | 2012 | Publication | Talanta : the international journal of pure and applied analytical chemistry | Abbreviated Journal | Talanta |
Volume | 101 | Issue | Pages | 420-427 | |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | A method for the classification of individual aerosol particles using computer controlled electron probe microanalysis is presented. It is based on chemical boundary conditions (CBC) and enables quick and easy processing of a large set of elemental concentration data (mass%), derived from the X-ray spectra of individual particles. The particles are first classified into five major classes (sea salt related, secondary inorganic, minerals, iron-rich and carbonaceous), after which advanced data mining can be performed by examining the elemental composition of particles within each class into more detail (e.g., by ternary diagrams). The CBC method is validated and evaluated by comparing its results with the output obtained with hierarchical cluster analysis (HCA) for well-known standard particles as well as real aerosol particles collected with a cascade impactor. The CBC method gives reliable results and has a major advantage compared to HCA. CBC is based on boundary conditions that are derived from chemical logical thinking and does not require a translation of a mathematical algorithm output as does HCA. Therefore, the CBC method is more objective and enables comparison between samples without intermediate steps. | ||||
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Language | Wos | 000313084400061 | Publication Date | 2012-09-30 | |
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ISSN | 0039-9140; 1873-3573 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.162 | Times cited | 3 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 4.162; 2012 IF: 3.498 | ||
Call Number | UA @ admin @ c:irua:101336 | Serial | 5511 | ||
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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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Language | Wos | 000648505900008 | Publication Date | 2021-05-04 | |
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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 | 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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Language | Wos | 000522701700005 | Publication Date | 2020-03-31 | |
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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 | 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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Language | Wos | 000451246100002 | Publication Date | 2018-11-20 | |
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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 | 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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Language | Wos | 000444060600028 | Publication Date | 2018-09-04 | |
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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 | 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 | 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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Language | English | Wos | 000381654800020 | Publication Date | 2016-07-26 |
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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 | 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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Language | Wos | 000580426800091 | Publication Date | 2020-10-06 | |
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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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