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	Author	Bogaerts, A.; Gijbels, R.
	Title	Modeling of glow discharges: what can we learn from it?			Type	A3 Journal article
	Year	1997	Publication	Analytical chemistry A-pages	Abbreviated Journal
	Volume	69	Issue		Pages	719-727
	Keywords	A3 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:19611			Serial	2126
Permanent link to this record



	Author	Balazs, L.; Gijbels, R.; Vertes, A.
	Title	Expansion of laser-generated plumes near the plasma ignition threshold			Type	A1 Journal article
	Year	1991	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	63	Issue		Pages	314-320
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	A1991EX23500005	Publication Date	0000-00-00
	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	5.636	Times cited	71	Open Access
	Notes				Approved	no
	Call Number	UA @ lucian @ c:irua:704			Serial	1134
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
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Wos	000381654800020	Publication Date	2016-07-26
	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	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
Permanent link to this record



	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.
	Address
	Corporate Author				Thesis
	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.
	Address
	Corporate Author				Thesis
	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	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.
	Address
	Corporate Author				Thesis
	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	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.
	Address
	Corporate Author				Thesis
	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	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).
	Address
	Corporate Author				Thesis
	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	Rahemi, V.; Trashin, S.; Hafideddine, Z.; Van Doorslaer, S.; Meynen, V.; Gorton, L.; De Wael, K.
	Title	Amperometric flow-injection analysis of phenols induced by reactive oxygen species generated under daylight irradiation of titania impregnated with horseradish peroxidase			Type	A1 Journal article
	Year	2020	Publication	Analytical Chemistry	Abbreviated Journal	Anal Chem
	Volume	92	Issue	92	Pages	3643-3649
	Keywords	A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Titanium dioxide (TiO2) is a unique material for biosensing applications due to its capability of hosting enzymes. For the first time, we show that TiO2 can accumulate reactive oxygen species (ROS) under daylight irradiation and can support the catalytic cycle of horseradish peroxidase (HRP) without the need of H2O2 to be present in the solution. Phenolic compounds, such as hydroquinone (HQ) and 4-aminophenol (4-AP), were detected amperometrically in flow-injection analysis (FIA) mode via the use of an electrode modified with TiO2 impregnated with HRP. In contrast to the conventional detection scheme, no H2O2 was added to the analyte solution. Basically, the inherited ability of TiO2 to generate reactive oxygen species is used as a strategy to avoid adding H2O2 in the solution during the detection of phenolic compounds. Electron paramagnetic resonance (EPR) spectroscopy indicates the presence of ROS on titania which, in interaction with HRP, initiate the electrocatalysis toward phenolic compounds. The amperometric response to 4-AP was linear in the concentration range between 0.05 and 2 μM. The sensitivity was 0.51 A M–1 cm–2, and the limit of detection (LOD) 26 nM. The proposed sensor design opens new opportunities for the detection of phenolic traces by HRP-based electrochemical biosensors, yet in a more straightforward and sensitive way following green chemistry principles of avoiding the use of reactive and harmful chemical, such as H2O2.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000518234700023	Publication Date	2020-01-27
	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	3	Open Access
	Notes	; The authors thank Scientific Reseatch-Flanders (F-WO) (grant 12T4219N) for funding. ;			Approved	Most recent IF: 7.4; 2020 IF: 6.32
	Call Number	UA @ admin @ c:irua:166241			Serial	5463
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	Author	Pilehvar, S.; Mehta, J.; Dardenne, F.; Robbens, J.; Blust, R.; De Wael, K.
	Title	Aptasensing of chloramphenicol in the presence of its analogues : reaching the maximum residue limit			Type	A1 Journal article
	Year	2012	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	84	Issue	15	Pages	6753-6758
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	A novel label-free folding induced aptamer-based electrochemical biosensor for the detection of chloramphenicol (CAP) in the presence of its analogues has been developed. CAP is a broad-spectrum antibiotic which has lost its favor due to its serious adverse toxic effects on human health. Aptamers are artificial nucleic acid ligands (ssDNA or RNA) able to specifically recognize a target such as CAP. In this article, the aptamers are fixed onto a gold electrode surface by a self-assembly approach. In the presence of CAP, the unfolded ssDNA on the electrode surface changes to a hairpin structure bringing the target molecules close to the surface and trigger electron transfer. Detection limits were determined to be 1.6×10-9 mol L-1. In addition, thiamphenicol (TAP) and florfenicol (FF), antibiotics with a similar structure to CAP, did not influence the performance of the aptasensor, suggesting a good selectivity of the CAP-aptasensor. Simplicity and lower detection limit (because of the home-selected aptamers) make that the electrochemical aptasensor is suitable for practical use in the detection of CAP in milk samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000307159200069	Publication Date	2012-06-20
	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	68	Open Access
	Notes	; ;			Approved	Most recent IF: 6.32; 2012 IF: 5.695
	Call Number	UA @ admin @ c:irua:98816			Serial	5477
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	Author	Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K.
	Title	Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	3	Pages	2035-2041
	Keywords	A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	Electrochemistry and exploiting electrochemical fingerprints is a potent approach to address newly emerging surveillance needs, for instance for antibiotics. However, a comprehensive insight in the electrochemical oxidation behaviour and mechanism is re-quired for this sensing strategy. To address the lack in knowledge of the voltammetric behaviour of the cephalosporins antibiotics, a selection of cephalosporin antibiotics and two main intermediates were subjected to an electrochemical study of their redox behaviour by means of pulsed voltammetric techniques and small-scale electrolysis combined with HPLC-MS/MS analyses. Sur-prisingly, the detected oxidation products did not fit the earlier suggested oxidation of the sulfur group to the corresponding sul-foxide. The influence of different side chains, both at the three and the seven position of the β-lactam core structure on the elec-trochemical fingerprint were investigated. Additional oxidation signals at lower potentials were elucidated and linked to different side chains. These signals were further exploited to allow simultaneous detection of different cephalosporins in one voltammetric sweep. These fundamental insights can become the building blocks for an new on-site screening method.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000458220300055	Publication Date	2019-01-03
	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	6	Open Access
	Notes	; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:156046			Serial	5497
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	Author	van der Snickt, G.; Dik, J.; Cotte, M.; Janssens, K.; Jaroszewicz, J.; de Nolf, W.; Groenewegen, J.; van der Loeff, L.
	Title	Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques			Type	A1 Journal article
	Year	2009	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	81	Issue	7	Pages	2600-2610
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	On several paintings of James Ensor (1860−1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (ì-XANES) experiments show that sulfur, originally present in sulfidic form (S2−), is oxidized during the transformation to the sulfate form (S6+). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO4·2H2O) and ammonium cadmium sulfate [(NH4)2Cd(SO4)2] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1−2 ìm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR ì-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000264759400025	Publication Date	2009-03-11
	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	91	Open Access
	Notes				Approved	Most recent IF: 6.32; 2009 IF: 5.214
	Call Number	UA @ admin @ c:irua:76415			Serial	5501
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	Author	Cagno, S.; Brede, D.A.; Nuyts, G.; Vanmeert, F.; Pacureanu, A.; Tucoulou, R.; Cloetens, P.; Falkenberg, G.; Janssens, K.; Salbu, B.; Lind, O.C.
	Title	Combined computed nanotomography and nanoscopic x-ray fluorescence imaging of cobalt nanoparticles in caenorhabditis elegans			Type	A1 Journal article
	Year	2017	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	89	Issue	21	Pages	11435-11442
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Synchrotron radiation phase-contrast computed nanotomography (nano-CT) and two-and three-dimensional (2D and 3D) nanoscopic X-ray fluorescence (nano-XRF) were used to investigate the internal distribution of engineered-cobalt nanoparticles (Co NPs) in exposed individuals of the nematode Caenorhabditis elegans. Whole-nematodes and selected tissues and organs were 3D-rendered: anatomical 3D renderings with 50 nm voxel size enabled the visualization of spherical nanoparticle aggregates. with size tip to 200 nm within intact C. elegans. A 20 X 37 nm(2) high-brilliance beam was employed to obtain XRF elemental distribution maps of entire nematodes or anatomical details such as embryos, which could be compared with the CT data, These maps showed Co NPs to be predominantly present within the intestine and the epithelium, and they were not colocalized with Zn granules found in the lysosonie-containing vesicles or Fe agglomerates in the intestine. Iterated XRF scanning of a specimen at 0 degrees and 90 degrees angles suggested that NP aggregates were translocated into tissues outside of the intestinal lumen. Virtual-slicing by means of 2D XRF tomography, combined with holotomography, indicated presumable presence of individual NP aggregates inside the uterus and within embryos.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000414887000041	Publication Date	2017-10-10
	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	6.32	Times cited	13	Open Access
	Notes	; This study has been funded by the Norwegian Research Council through its Centre of Excellence (CoE) funding scheme (Project 223268/F50). We gratefully acknowledge ESRF and DESY for granting beamtime and Karl Andreas Jensen for performing ICPMS analysis. We thank Erica Maremonti for supplying the phase-contrast image used in Figure ^1A. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:147383			Serial	5520
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	Author	van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L.
	Title	Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh			Type	A1 Journal article
	Year	2012	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	84	Issue	23	Pages	10221-10228
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO4 center dot H2O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 mu m sized globular agglomerations. Here, we study cadmium yellow in the painting “Flowers in a blue vase” by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (mu-XRD), microscopic X-ray absorption near-edge spectroscopy (mu-XANES), microscopic X-ray fluorescence (mu-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (mu-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO4 compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd2+ ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO42- anions, for their part, found a suitable reaction partner in Pb2+ ions stemming from a dissolved lead-based siccative that was added to the varnish to promote its drying. The resulting opaque anglesite compound in the varnish, in combination with the underlying CdC2O4 layer at the paint/varnish interface, account for the orange-gray crust that is disfiguring the painting on a macroscopic level. In this way, the results presented in this paper demonstrate how, through a judicious combined use of several microanalytical methods with speciation capabilities, many new insights can be obtained from two minute, but highly complex and heterogeneous paint samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000311815300013	Publication Date	2012-08-30
	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	59	Open Access
	Notes	; This research was supported by BELSPO via the Interuniversity Attraction Poles Programme (IUAP VI/16) and the S2-ART project (SD/RI/04A) and funded by Grants from the ESRF (EC-442) and PETRA-III (I-20120312 EC). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Kroller-Muller Museum and painting conservators Margje Leeuwestein and Esther Van Duijn are acknowledged for this pleasant cooperation and the authorization for the publication of the images in this article. ;			Approved	Most recent IF: 6.32; 2012 IF: 5.695
	Call Number	UA @ admin @ c:irua:105971			Serial	5526
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	Author	Hamidi-Asl, E.; Daems, D.; De Wael, K.; Van Camp, G.; Nagels, L.J.
	Title	Concentration related response potentiometric titrations to study the interaction of small molecules with large biomolecules			Type	A1 Journal article
	Year	2014	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	86	Issue	24	Pages	12243-12249
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In the present article, the utility of a special potentiometric titration approach for recognition and calculation of biomolecule/small molecule interactions is reported. This approach is fast, sensitive, reproducible and inexpensive in comparison to the other methods for the determination of the association constant values (Ka) and the interaction energies (ΔG). The potentiometric titration measurement is based on the use of a classical polymeric membrane indicator electrode in a solution of the small molecule ligand. The biomolecule is used as a titrant. The potential is measured versus a reference electrode and transformed to a concentration related signal over the entire concentration interval, also at low concentrations, where the mV (y-axis) versus logcanalyte (x-axis) potentiometric calibration curve is not linear. In the procedure, the Ka is calculated for the interaction of cocaine with a cocaine binding aptamer and with an anti-cocaine antibody. To study the selectivity and cross-reactivity, other oligonucleotides and aptamers are tested, as well as other small ligand molecules such as tetrakis (4-chlorophenyl)borate, metergoline, lidocaine, and bromhexine. The calculated Ka compared favorably to the value reported in the literature using SPR. The potentiometric titration approach called Concentration related Response Potentiometry, is used to study molecular interaction for 7 macromolecular target molecules and 4 small molecule ligands.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000346683900048	Publication Date	2014-11-13
	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	10	Open Access
	Notes	; Financial support for this work was provided by the University of Antwerp by granting L.J.N., K.D.W, G.V.C., and Ronny Blust a POC interdisciplinary research project. ;			Approved	Most recent IF: 6.32; 2014 IF: 5.636
	Call Number	UA @ admin @ c:irua:120164			Serial	5548
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	Author	Monico, L.; Janssens, K.; Miliani, C.; van der Snickt, G.; Brunetti, B.G.; Guidi, M.C.; Radepont, M.; Cotte, M.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 4 : artificial aging of model samples of co-precipitates of lead chromate and lead sulfate			Type	A1 Journal article
	Year	2013	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	85	Issue	2	Pages	860-867
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO4 and PbCr1xSxO4) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO4 and PbCr1xSxO4 were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr1xSxO4, rich in SO42 (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models chemical composition, no change in the S-oxidation state was observed. Analyses employing UVvisible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000313668400032	Publication Date	2012-10-10
	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	6.32	Times cited	49	Open Access
	Notes	; This research was supported by grants from ESRF (experiment EC-799), the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16), and the BELSPO-SDD S2-ART (SD/RI/04) project. The text also presents results from GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects G.0704.08 and G.01769.09. The EU FP7 programme CHARISMA (Grant Agreement 228330) and MIUR (PRIN08, Materiali e sistemi innovativi per la conservazione dell'arte contemporanea 2008 FFXXN9) are also acknowledged. ;			Approved	Most recent IF: 6.32; 2013 IF: 5.825
	Call Number	UA @ admin @ c:irua:110471			Serial	5569
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	Author	Monico, L.; Janssens, K.; Vanmeert, F.; Cotte, M.; Brunetti, B.G.; van der Snickt, G.; Leeuwestein, M.; Plisson, J.S.; Menu, M.; Miliani, C.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : part 5 : effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints			Type	A1 Journal article
	Year	2014	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	86	Issue	21	Pages	10804-10811
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The darkening of lead chromate yellow pigments, caused by a reduction of the chromate ions to Cr(III) compounds, is known to affect the appearance of several paintings by Vincent van Gogh. In previous papers of this series, we demonstrated that the darkening is activated by light and depends on the chemical composition and crystalline structure of the pigments. In this work, the results of Part 2 are extended and complemented with a new study aimed at deepening the knowledge of the nature and distribution of Cr and S species at the interface between the chrome yellow paint and the nonoriginal coating layer. For this purpose, three microsamples from two varnished paintings by Van Gogh and a waxed low relief by Gauguin (all originally uncoated) have been examined. Because nonoriginal coatings are often present in artwork by Van Gogh and contemporaries, the understanding of whether or not their application has influenced the morphological and/or physicochemical properties of the chrome yellow paint underneath is relevant in view of the conservation of these masterpieces. In all the samples studied, microscopic X-ray fluorescence (mu-XRF) and X-ray absorption near edge structure (mu-XANES) investigations showed that Cr(III)-based alteration products are present in the form of grains inside the coating (generally enriched of S species) and also homogeneously widespread at the paint surface. The distribution of Cr(III) species may be explained by the mechanical friction caused by the coating application by brush that picked up and redistributed the superficial Cr compounds, likely already present in the reduced state as result of the photodegradation process. The analysis of the XANES profiles allowed us to obtain new insights into the nature of the Cr(III) alteration products, that were identified as sulfate-, oxide-, organo-metal-, and chloride-based compounds. Building upon the knowledge acquired through the examination of original paint samples and from the investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000344510200043	Publication Date	2014-10-10
	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	6.32	Times cited	25	Open Access
	Notes	; This research was supported by the Italian projects PRIN (SICH) and PON (ITACHA). The text also presents results from Interuniversity Attraction Poles Programme Belgian Science Policy (S2-ART project S4DA), GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments EC-799 and EC-1051). L.M. acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam) and Muriel Geldof (Cultural Heritage Agency of The Netherlands) for selecting and sharing the information on the cross-section taken from Bank of the Seine. All the staff of the Van Gogh Museum, the Kroller-Muller Museum, and the Musee d'Orsay are acknowledged for the agreeable cooperation. ;			Approved	Most recent IF: 6.32; 2014 IF: 5.636
	Call Number	UA @ admin @ c:irua:122100			Serial	5570
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	Author	Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples			Type	A1 Journal article
	Year	2011	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	83	Issue	4	Pages	1224-1231
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000287176900012	Publication Date	2011-02-14
	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	84	Open Access
	Notes	; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ;			Approved	Most recent IF: 6.32; 2011 IF: 5.856
	Call Number	UA @ admin @ c:irua:88795			Serial	5571
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	Author	Anaf, W.; Trashin, S.; Schalm, O.; van Dorp, D.; Janssens, K.; De Wael, K.
	Title	Electrochemical photodegradation study of semiconductor pigments : influence of environmental parameters			Type	A1 Journal article
	Year	2014	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	86	Issue	19	Pages	9742-9748
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
	Abstract	Chemical transformations in paintings often induce discolorations, disturbing the appearance of the image. For an appropriate conservation of such valuable and irreplaceable heritage objects, it is important to have a good know-how on the degradation processes of the (historical) materials: which pigments have been discolored, what are the responsible processes, and which (environmental) conditions have the highest impact on the pigment degradation and should be mitigated. Pigment degradation is already widely studied, either by analyzing historical samples or by accelerated weathering experiments on dummies. However, in historic samples several processes may have taken place, increasing the complexity of the current state, while aging experiments are time-consuming due to the often extended aging period. An alternative method is proposed for a fast monitoring of degradation processes of semiconductor pigments, using an electrochemical setup mimicking the real environment and allowing the identification of harmful environmental parameters for each pigment. Examples are given for the pigments cadmium yellow (CdS) and vermilion (α-HgS).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000343017100058	Publication Date	2014-08-27
	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	18	Open Access
	Notes	; ;			Approved	Most recent IF: 6.32; 2014 IF: 5.636
	Call Number	UA @ admin @ c:irua:118834			Serial	5593
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	Author	Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K.
	Title	Electrochemical strategies for adulterated heroin samples			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	12	Pages	7920-7928
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Electrochemical strategies to selectively detect heroin in street samples without the use of complicated electrode modifications were developed for the first time. For this purpose, heroin, mixing agents (adulterants, cutting agent, and impurities), and their binary mixtures were subjected to square wave voltammetry measurements at bare graphite electrodes at pH 7.0 and pH 12.0, in order to elucidate the unique electrochemical fingerprint of heroin and mixing agents as well as possible interferences or reciprocal influences. Adjusting the pH from pH 7.0 to pH 12.0 allowed a more accurate detection of heroin in the presence of most common mixing agents. Furthermore, the benefit of introducing a preconditioning step prior to running square wave voltammetry on the electrochemical fingerprint enrichment was explored. Mixtures of heroin with other drugs (cocaine, 3,4-methylenedioxymethamphetamine, and morphine) were also tested to explore the possibility of their discrimination and simultaneous detection. The feasibility of the proposed electrochemical strategies was tested on realistic heroin street samples from forensic cases, showing promising results for fast, on-site detection tools of drugs of abuse.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000472682000056	Publication Date	2019-05-30
	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	2	Open Access
	Notes	; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge IOF (UAntwerp) and Belspo for financial support. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:160061			Serial	5596
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	Author	Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K.
	Title	Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	18	Pages	11582-11588
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000487156900016	Publication Date	2019-08-20
	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	2	Open Access
	Notes	; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:163784			Serial	5621
Permanent link to this record



	Author	Bulska, E.; Wysocka, I.A.; Wierzbicka, M.H.; Proost, K.; Janssens, K.; Falkenberg, G.
	Title	In vivo investigation of the distribution and the local speciation of selenium in Allium cepa L. by means of microscopic X-ray absorption near-edge structure spectroscopy and confocal microscopic X-ray fluorescence analysis			Type	A1 Journal article
	Year	2006	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	78	Issue	22	Pages	7616-7624
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000242021400003	Publication Date	2006-10-10
	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	6.32	Times cited	56	Open Access
	Notes				Approved	Most recent IF: 6.32; 2006 IF: 5.646
	Call Number	UA @ admin @ c:irua:60714			Serial	5659
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	Author	De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K.
	Title	Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	8	Pages	5290-5297
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000430512200049	Publication Date	2018-02-23
	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	6.32	Times cited	8	Open Access
	Notes	; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:149528			Serial	5693
Permanent link to this record



	Author	Vanmeert, F.; de Nolf, W.; De Meyer, S.; Dik, J.; Janssens, K.
	Title	Macroscopic X-ray powder diffraction scanning, a new method for highly selective chemical imaging of works of art : instrument optimization			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	11	Pages	6436-6444
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In the past decade macroscopic X-ray fluorescence imaging (MA-XRF) has become established as a method for the noninvasive investigation of flat painted surfaces, yielding large scale elemental maps. MA-XRF is limited by a lack of specificity, only allowing for indirect pigment identification based on the simultaneous presence of chemical elements. The high specificity of X-ray powder diffraction (XRPD) mapping is already being exploited at synchrotron facilities for investigations at the (sub)microscopic scale, but the technique has not yet been employed using lab sources. In this paper we present the development of a novel MA-XRPD/XRF instrument based on a laboratory X-ray source. Several combinations of X-ray sources and area detectors are evaluated in terms of their spatial and angular resolution and their sensitivity. The highly specific imaging capability of the combined MA-XRPD/XRF instrument is demonstrated on a 15th/16th century illuminated manuscript directly revealing the distribution of a large number of inorganic pigments, including the uncommon yellow pigment massicot (o-PbO). The case study illustrates the wealth of new mapping information that can be obtained in a noninvasive manner using the laboratory MA-XRPD/XRF instrument.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000434893200019	Publication Date	2018-04-06
	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	11	Open Access
	Notes	; The authors thank the persons involved at Incoatec GmbH, imXPAD SAS and Dectris Ltd. for loaning us some of their products over the past years. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” Project and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:151993			Serial	5701
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	Author	Vanmeert, F.; de Nolf, W.; Dik, J.; Janssens, K.
	Title	Macroscopic X-ray powder diffraction scanning : possibilities for quantitative and depth-selective parchment analysis			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	11	Pages	6445-6452
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	At or below the surface of painted works of art, valuable information is present that provides insights into an objects past, such as the artists technique and the creative process that was followed or its conservation history but also on its current state of preservation. Various noninvasive techniques have been developed over the past 2 decades that can probe this information either locally (via point analysis) or on a macroscopic scale (e.g., full-field imaging and raster scanning). Recently macroscopic X-ray powder diffraction (MA-XRPD) mapping using laboratory X-ray sources was developed. This method can visualize highly specific chemical distributions at the macroscale (dm(2)). In this work we demonstrate the synergy between the quantitative aspects of powder diffraction and the noninvasive scanning capability of MA-XRPD highlighting the potential of the method to reveal new types of information. Quantitative data derived from a 15th/16th century illuminated sheet of parchment revealed three lead white pigments with different hydrocerussite-cerussite compositions in specific pictorial elements, while quantification analysis of impurities in the blue azurite pigment revealed two distinct azurite types: one rich in barite and one in quartz. Furthermore, on the same artifact, the depth-selective possibilities of the method that stem from an exploitation of the shift of the measured diffraction peaks with respect to reference data are highlighted. The influence of different experimental parameters on the depth-selective analysis results is briefly discussed. Promising stratigraphic information could be obtained, even though the analysis is hampered by not completely understood variations in the unit cell dimensions of the crystalline pigment phases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000434893200020	Publication Date	2018-04-06
	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	6	Open Access
	Notes	; The authors thank Incoatec GmbH for giving us the opportunity to test the I mu S Cu X-ray source. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:151994			Serial	5702
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	Author	Ranjbari, E.; Hadjmohammadi, M.R.; Kiekens, F.; De Wael, K.
	Title	Mixed hemi/ad-micelle sodium dodecyl sulfate-coated magnetic iron oxide nanoparticles for the efficient removal and trace determination of rhodamine-B and rhodamine-6G			Type	A1 Journal article
	Year	2015	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	87	Issue	15	Pages	7894-7901
	Keywords	A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g1, respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L1 of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL1. Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000359277900056	Publication Date	2015-07-08
	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	36	Open Access
	Notes	; ;			Approved	Most recent IF: 6.32; 2015 IF: 5.636
	Call Number	UA @ admin @ c:irua:126583			Serial	5730
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	Author	Kempenaers, L.; Janssens, K.; Vincze, L.; Vekemans, B.; Somogyi, A.; Drakopoulos, M.; Simionovici, A.S.; Adams, F.
	Title	A Monte Carlo model for studying the microheterogeneity of trace elements in reference materials by means of synchrotron microscopic X-ray fluorescence			Type	A1 Journal article
	Year	2002	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	74	Issue	19	Pages	5017-5026
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000178418100031	Publication Date	2002-09-30
	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	21	Open Access
	Notes				Approved	Most recent IF: 6.32; 2002 IF: 5.094
	Call Number	UA @ admin @ c:irua:39871			Serial	5734
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	Author	Neven, L.; Thiruvottriyur Shanmugam, S.; Rahemi, V.; Trashin, S.; Sleegers, N.; Carrion, E.N.; Gorun, S.M.; De Wael, K.
	Title	Optimized photoelectrochemical detection of essential drugs bearing phenolic groups			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	15	Pages	9962-9969
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The World Health Organization (WHO) model “List of Essential Medicines” includes among indispensable medicines antibacterials and pain and migraine relievers. Monitoring their concentration in the environment, while challenging, is important in the context of antibiotic resistance as well as their production of highly toxic compounds via hydrolysis. Traditional detection methods such as high-performance liquid chromatography (HPLC) or LC combined with tandem mass spectrometry or UV-vis spectroscopy are time-consuming, have a high cost, require skilled operators and are difficult to adapt for field operations. In contrast, (electrochemical) sensors have elicited interest because of their rapid response, high selectivity, and sensitivity as well as potential for on-site detection. Previously, we reported a novel sensor system based on a type II photosensitizer, which combines the advantages of enzymatic sensors (high sensitivity) and photoelectrochemical sensors (easy baseline subtraction). Under red-light illumination, the photosensitizer produces singlet oxygen which oxidizes phenolic compounds present in the sample. The subsequent reduction of the oxidized phenolic compounds at the electrode surface gives rise to a quantifiable photocurrent and leads to the generation of a redox cycle. Herein we report the optimization in terms of pH and applied potential of the photoelectrochemical detection of the hydrolysis product of paracetamol, i.e., 4-aminophenol (4-AP), and two antibacterials, namely, cefadroxil (CFD, beta-lactam antibiotic) and doxycycline (DXC, tetracycline antibiotic). The optimized conditions resulted in a detection limit of 0.2 mu mol L-1 for DXC, but in a 10 times higher sensitivity, 20 nmol L-1, for CFD. An even higher sensitivity, 7 nmol L-1, was noted for 4-AP.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000480499200086	Publication Date	2019-06-25
	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	2	Open Access
	Notes	; FWO and UA-BOF are acknowledged for financial support. The Center for Functional Materials of Seton Hall University is thanked for support (S.M.G. and E.N.C.). Joren Van Loon is thanked for the graphical abstract. This research was supported by the medium scale research infrastructure funding Hercules funding (SEM). ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:161831			Serial	5763
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	Author	Vincze, L.; Somogyi, A.; Osán, J.; Vekemans, B.; Török, S.; Janssens, K.; Adams, F.
	Title	Quantitative trace element analysis of individual fly ash particles by means of X-ray microfluorescence			Type	A1 Journal article
	Year	2002	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	74	Issue		Pages	1128-1135
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000174187900032	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	6.32	Times cited	44	Open Access
	Notes				Approved	Most recent IF: 6.32; 2002 IF: 5.094
	Call Number	UA @ admin @ c:irua:38377			Serial	5796
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	Author	Alvarez-Martin, A.; Cleland, T.P.; Kavich, G.M.; Janssens, K.; Newsome, G.A.
	Title	Rapid evaluation of the debromination mechanism of eosin in oil paint by direct analysis in real time and direct infusion-electrospray ionization mass spectrometry			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	16	Pages	10856-10863
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Eosin is a synthetic organic colorant prone to fading under the influence of light. On the basis of the growing interest in the understanding of the discoloration mechanism of eosin-based lakes, this study compares the ability of two ultrafast and ultrasensitive mass spectrometry techniques to detect eosin derivatives in complex matrices, such as oil media without the use of conventional separation columns or additional sample preparation protocols. Direct analysis in real time mass spectrometry (DART-MS) and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) were used to characterize the degradation pathway of eosin in oil media. The analysis protocols developed in this study are applied to discern the degradation mechanism of the lake pigment eosin (comprising the molecule per se complexed to an inorganic substrate) dispersed in linseed oil to create an oil paint. The analysis of oil paints by high resolution MS without an extraction methodology that modifies the system chemistry allowed us to identify the degradation forms without causing any additional fragmentation. Both techniques revealed the primary photodegradation pathway of eosin in linseed oil, and DI-ESI-MS provided additional information on the native conformation of the lake.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000482545300069	Publication Date	2019-07-30
	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	3	Open Access
	Notes	; The authors would like to acknowledge the SolarPaint project (GOA program, Antwerp University Research Council) and Smithsonian Institution for financial support. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:162879			Serial	5800
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