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	Author	Parrilla, M.; Sena-Torralba, A.; Steijlen, A.; Morais, S.; Maquieira, Á.; De Wael, K.
	Title	A 3D-printed hollow microneedle-based electrochemical sensing device for in situ plant health monitoring			Type	A1 Journal article
	Year	2024	Publication	Biosensors and bioelectronics	Abbreviated Journal
	Volume	251	Issue		Pages	116131-116139
	Keywords	A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Plant health monitoring is devised as a new concept to elucidate in situ physiological processes. The need for increased food production to nourish the growing global population is inconsistent with the dramatic impact of climate change, which hinders crop health and exacerbates plant stress. In this context, wearable sensors play a crucial role in assessing plant stress. Herein, we present a low-cost 3D-printed hollow microneedle array (HMA) patch as a sampling device coupled with biosensors based on screen-printing technology, leading to affordable analysis of biomarkers in the plant fluid of a leaf. First, a refinement of the 3D-printing method showed a tip diameter of 25.9 ± 3.7 μm with a side hole diameter on the microneedle of 228.2 ± 18.6 μm using an affordable 3D printer (<500 EUR). Notably, the HMA patch withstanded the forces exerted by thumb pressing (i.e. 20-40 N). Subsequently, the holes of the HMA enabled the fluid extraction tested in vitro and in vivo in plant leaves (i.e. 13.5 ± 1.1 μL). A paper-based sampling strategy adapted to the HMA allowed the collection of plant fluid. Finally, integrating the sampling device onto biosensors facilitated the in situ electrochemical analysis of plant health biomarkers (i.e. H2O2, glucose, and pH) and the electrochemical profiling of plants in five plant species. Overall, this electrochemical platform advances precise and versatile sensors for plant health monitoring. The wearable device can potentially improve precision farming practices, addressing the critical need for sustainable and resilient agriculture in changing environmental conditions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001198047000001	Publication Date	2024-02-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0956-5663	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	12.6	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 12.6; 2024 IF: 7.78
	Call Number	UA @ admin @ c:irua:203204			Serial	8998
Permanent link to this record



	Author	Steijlen, A.S.M.; Parrilla, M.; Van Echelpoel, R.; De Wael, K.
	Title	Dual microfluidic sensor system for enriched electrochemical profiling and identification of illicit drugs on-site			Type	A1 Journal article
	Year	2024	Publication	Analytical chemistry	Abbreviated Journal
	Volume	96	Issue	1	Pages	590-598
	Keywords	A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Electrochemical sensors have emerged as a new analytical tool for illicit drug detection to facilitate ultrafast and accurate identification of suspicious compounds on-site. Drugs of abuse can be identified using their unique voltammetric fingerprint at a given pH. Today, the right buffer solution is manually selected based on drug appearance, and in some cases, a consecutive analysis in two different pH solutions is required. In this work, we present a disposable microfluidic multichannel sensor system that automatically records fingerprints in two pH solutions (e.g., pH 5 and pH 12). This system has two advantages. It will overcome the manual selection of a buffer solution at the right pH, decrease analysis time, and minimize the risk of human errors. Second, the combination of two fingerprints, the superfingerprint, contains more detailed information about the samples, which enhances the selectivity of the analytical technique. First, real-time pH measurements proved that the sample can be brought to the desired pH within a minute. Subsequently, an electrochemical study on the microfluidic platform with 1 mM illicit drug standards of MDMA, cocaine, heroin, and methamphetamine showed that the characteristic voltammetric fingerprints and peak potentials are reproducible, also in the presence of common cutting agents. Finally, the microfluidic concept was validated with real confiscated samples, showing promising results for the user-friendly identification of drugs of abuse. In short, this paper presents a successful proof-of-concept study of a multichannel microfluidic sensor system to enrich the fingerprints of illicit drugs at pH 5 and pH 12, thus providing a low-cost, portable, and rapid identification system of illicit drugs with minimal user intervention.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001139443500001	Publication Date	2023-12-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.4	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 7.4; 2024 IF: 6.32
	Call Number	UA @ admin @ c:irua:201877			Serial	9024
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	Author	Van Echelpoel, R.; De Wael, K.
	Title	Voltammetric drug testing makes sense at the border			Type	A1 Journal article
	Year	2024	Publication	Nature Reviews Chemistry	Abbreviated Journal
	Volume		Issue		Pages	1-2
	Keywords	A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	The European BorderSens project leverages voltammetric sensors, developed with end-users' input, to rapidly and accurately detect illicit drugs. By embracing practicalities and validation, this technology has the potential to combat the illicit drug problem.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001142000900001	Publication Date	2024-01-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2397-3358	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:202646			Serial	9112
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	Author	Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K.
	Title	Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings			Type	A1 Journal article
	Year	2017	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	89	Issue	89	Pages	3326-3334
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken.
	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	Janssens, K.; van der Snickt, G.; Vanmeert, F.; Legrand, S.; Nuyts, G.; Alfeld, M.; Monico, L.; Anaf, W.; de Nolf, W.; Vermeulen, M.; Verbeeck, J.; De Wael, K.
	Title	Non-invasive and non-destructive examination of artistic pigments, paints, and paintings by means of X-Ray methods			Type	A1 Journal article
	Year	2016	Publication	Topics in Current Chemistry	Abbreviated Journal	Topics Curr Chem
	Volume	374	Issue	374	Pages	81
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Recent studies are concisely reviewed, in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples, and/or entire paintings from the seventeenth to the early twentieth century painters. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging, as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic XRF is a variant of the method that is well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi-layers, on the length scale from 1 to 100 μm inside micro-samples taken from paintings. In the context of the characterization of artists pigments subjected to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red spectroscopy and/or Raman microscopy since these methods deliver complementary information of high molecular specificity at more or less the same length scale as the X-ray microprobe techniques. Since microscopic investigation of a relatively limited number of minute paint samples, taken from a given work of art, may not yield representative information about the entire artefact, several methods for macroscopic, non-invasive imaging have recently been developed. Those based on XRF scanning and full-field hyperspectral imaging appear very promising; some recent published results are discussed.
	Address
	Corporate Author				Thesis
	Publisher	Springer international publishing ag	Place of Publication	Cham	Editor
	Language		Wos	000391178900006	Publication Date	2016-11-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2365-0869;2364-8961;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.033	Times cited	50	Open Access
	Notes	; ;			Approved	Most recent IF: 4.033
	Call Number	UA @ lucian @ c:irua:139930UA @ admin @ c:irua:139930			Serial	4443
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	Author	De Jong, M.; Sleegers, N.; Florea, A.; Van Loon, J.; van Nuijs, A.L.N.; Samyn, N.; De Wael, K.
	Title	Unraveling the mechanisms behind the complete suppression of cocaine electrochemical signals by chlorpromazine, promethazine, procaine, and dextromethorphan			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	24	Pages	15453-15460
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre; Product development
	Abstract	The present work investigates the challenges accompanied by the electrochemical cocaine detection in physiological conditions (pH 7) in the presence of chlorpromazine, promethazine, procaine, and dextromethorphan, frequently used cutting agents in cocaine street samples. The problem translates into the absence of the cocaine oxidation signal (signal suppression) when in a mixture with one of these compounds, leading to false negative results. Although a solution to this problem was provided through earlier experiments of our group, the mechanisms behind the suppression are now fundamentally investigated via electrochemical and liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) strategies. The latter was used to confirm the passivation of the electrodes due to their interaction with promethazine and chlorpromazine. Electron transfer mechanisms were further identified via linear sweep voltammetry. Next, adsorption experiments were performed on the graphite screen printed electrodes both with and without potential assistance in order to confirm if the suppression of the cocaine signals is due to passivation induced by the cutting agents or their oxidized products. The proposed strategies allowed us to identify the mechanisms of cocaine suppression for each cutting agent mentioned. Suppression due to procaine and dextromethorphan is caused by fouling of the electrode surface by their oxidized forms, while for chlorpromazine and promethazine the suppression of the cocaine signal is related to the strong adsorption of these (nonoxidized) cutting agents onto the graphite electrode surface. These findings provide fundamental insights in possible suppression and other interfering mechanisms using electrochemistry in general not only in the drug detection sector.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000503910600018	Publication Date	2019-11-14
	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		Open Access
	Notes	; The authors acknowledge financial support from IOF-SBO/POC (UAntwerp) and the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:165727			Serial	5887
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	Author	Bottari, F.; Moro, G.; Sleegers, N.; Florea, A.; Cowen, T.; Piletsky, S.; van Nuijs, A.L.N.; De Wael, K.
	Title	Electropolymerized o-phenylenediamine on graphite promoting the electrochemical detection of nafcillin			Type	A1 Journal article
	Year	2019	Publication	Electroanalysis	Abbreviated Journal	Electroanal
	Volume	32	Issue	32	Pages	135-141
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	By combining molecular modelling and electrochemistry we envision the creation of modified electrodes tailored for a more sensitive and selective detection of a single analyte. In this study we report on a graphite screen printed electrode modified with electropolymerized o-phenylenediamine, selected by rational design, which promotes the detection of nafcillin (NAF), an antibiotic. Parameters such as monomer concentration, pH and number of electropolymerization cycles were optimized to obtain the highest current signal for the target upon amperometric detection. NAF identification was based on the redox process at +1.1 V (vs pseudo Ag), ascribed to the oxidation of the C-7 side chain. With the optimized modification protocol, a two-fold increase in nafcillin signal could be obtained: the calibration plot in 0.1 M Britton-Robinson buffer pH 4 showed a limit of detection of 80 nM with improved sensitivity and reproducibility (RSD<5 %) compared to the detection at non-modified electrodes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000482596300001	Publication Date	2019-08-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1040-0397	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.851	Times cited	1	Open Access
	Notes	; FB and GM devised the study and performed the experiments, FB wrote the original draft of the paper and analysed the data, NS and AvN performed the MS experiments, AF helped with the optimization of the protocol and correction of the first draft, TC and SP performed the rational monomer design, KdW supervised the work and corrected the final draft. All authors gave their suggestions and corrections to the final version of the paper. This work was financially supported by the University of Antwerp (BOF) and the Research Foundation Flanders (FWO). ;			Approved	Most recent IF: 2.851
	Call Number	UA @ admin @ c:irua:162870			Serial	5601
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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
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	Author	Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Govindan, M.; Covaci, A.; Van Grieken, R.
	Title	Spatial monitoring of organohalogen compounds in surface water and sediments of a rural-urban river basin in Tanzania			Type	A1 Journal article
	Year	2013	Publication	The science of the total environment	Abbreviated Journal	Sci Total Environ
	Volume	447	Issue		Pages	186-197
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	The presence of persistent organic pollutants in Tanzanian environment is not well monitored despite the existing pollution potential from a number of sources. In this study, we investigated for the first time, the concentration profiles of different organohalogen compounds such as organochlorine pesticide residues (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in environmental samples (water and sediments) from the Pangani river basin (PRB). The PRB is one of the largest drainage basins in Tanzania, with its watershed exposed to multiple input sources of trace organic contaminants. Surface water and sediments were sampled from 12 representative stations of diverse characteristics and land-use practices, in three distinct seasons, and extracted by liquidliquid and Soxhlet extraction methods, respectively. Water samples were analyzed by GC-ECD for OCPs only, while sediment samples were analyzed for OCPs, PCBs and PBDEs by GC/MS. Seven compounds, dominated by HCH isomers (5104460 pg/L) and DDT analogs (1601460 pg/L),were detected in the water samples. These concentrations are far below the WHO guidelines for drinking water quality. A total of 42 compounds (8 OCPs, 28 PCB congeners and 6 PBDE congeners) were detected in the sediment samples. Their respective total concentration ranges were 24510,230; 35711,000 and 382175 pg/g dry weight. The spatial distribution patterns and Hierarchical Cluster Analysis reflected the impact of historical agricultural usage in sugarcane plantations (OCPs), and urbanization (PCBs and PBDEs). Risk assessment using sediment quality guidelines indicated no ecotoxicological risks. The results we have found provide preliminary data on levels of the organic contaminants in Pangani river basin as a new insight on the environmental quality of the area.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000317538100022	Publication Date	2013-02-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.9	Times cited	42	Open Access
	Notes	; This research project was funded by the International Foundation for Science (IFS, Project Number W/4945-1). The authors wish to acknowledge the contribution of the Pangani Basin Water Office (PBWO) in Moshi, Tanzania; especially Ms. Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns, and Salim Lyimo in mapping of the study area. The contributions of Mr. Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterization; and Mr. Emmanuel Gwae, of the Government Chemists Laboratory Agency (GCLA) Dar es Salaam, Tanzania, for instrumental analysis of the water samples, are highly appreciated. Harieth Hellar-Kihampa acknowledges financial support from the Belgian Technical Agency (BTC). Govindan Malarvannan and Adrian Covaci acknowledge financial support from the University of Antwerp. ;			Approved	Most recent IF: 4.9; 2013 IF: 3.163
	Call Number	UA @ admin @ c:irua:105260			Serial	5836
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	Author	Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K.
	Title	Electrochemistry of intact versus degraded cephalosporin antibiotics facilitated by LC–MS analysis			Type	A1 Journal article
	Year	2021	Publication	Analytical Chemistry	Abbreviated Journal	Anal Chem
	Volume	93	Issue	4	Pages	2394-2402
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	The electrochemical detection of cephalosporins is a promising approach for the monitoring of cephalosporin levels in process waters. However, this class of antibiotics, like penicillins, is composed of chemically active molecules and susceptible to hydrolysis and aminolysis of the four membered β-lactam ring present. In order to develop a smart monitoring strategy for cephalosporins, the influence of degradation (hydrolysis and aminolysis) on the electrochemical fingerprint has to be taken into account. Therefore, an investigation was carried out to understand the changes of the voltammetric fingerprints upon acidic and alkaline degradation. Changes in fingerprints were correlated to the degradation pathways through the combination of square wave voltammetry and liquid chromatography quadrupole time-of-flight analysis. The characteristic electrochemical signals of the β-lactam ring disappeared upon hydrolysis. Additional oxidation signals that appeared after degradation were elucidated and linked to different degradation products, and therefore, enrich the voltammetric fingerprints with information of the state of the cephalosporins. The applicability of the electrochemical monitoring system was explored by the analysis of the intact and degraded industrial process waters containing the key intermediate 7-aminodeacetoxycephalosporanic acid (7-ADCA). Clearly, the intact process samples exhibited the expected core signals of 7-ADCA and could be quantified, while the degraded samples only showed the newly formed degradation products.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000618089100063	Publication Date	2021-01-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:176206			Serial	7864
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	Author	Schram, J.; Thiruvottriyur Shanmugam, S.; Sleegers, N.; Florea, A.; Samyn, N.; van Nuijs, A.L.N.; De Wael, K.
	Title	Local conversion of redox inactive molecules into redox active ones : a formaldehyde based strategy for the electrochemical detection of illicit drugs containing primary and secondary amines			Type	A1 Journal article
	Year	2021	Publication	Electrochimica Acta	Abbreviated Journal	Electrochim Acta
	Volume	367	Issue		Pages	137515
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	Electrochemical techniques have evidenced to be highly suitable for the development of portable, rapid and accurate screening methods for the detection of illicit drugs in seized samples. However, the redox inactivity of primary amines, one of the most common functional groups of illicit drugs, masks voltammetric detection in aqueous environment at carbon electrodes and, therefore, leads to false negative results if only these primary amines are present in the structures. This work explores the feasibility of a derivatisation approach that introduces formaldehyde in the measuring conditions in order to achieve methylation, via an Eschweiler-Clarke mechanism, of illicit drugs containing primary and secondary amines, using amphetamine (AMP) and methamphetamine (MET) as model molecules. As a result the electrochemical fingerprint is enriched and thereby the detectability enhanced. A combination of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOFMS) and square-wave voltammetric (SWV) measurements is employed to identify reaction products and link them to the observed redox peaks. Although an alkaline environment (pH 12.0) proved to increase the reaction yield, a richer electrochemical fingerprint (EF) is obtained in neutral conditions (pH 7.0). Similarly, the addition of formate improved the reaction conversion but reduced the EF by eliminating a redox peak that is attributed to side products formed in the absence of formate. To illustrate the applicability, the derivatisation strategy is applied to several prominent illicit drugs containing primary and secondary amines to demonstrate its EF enriching capabilities. Finally, real street samples from forensic seizures are analysed. Overall, this strategy unlocks the detectability of the hitherto undetectable AMP and other drugs only containing primary amines, while strongly facilitating the identification of MET and analogues. These findings are not limited to illicit drugs, the insights can ultimately be applied to other target molecules containing similar functional groups. (C) 2020 Published by Elsevier Ltd.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000607620700010	Publication Date	2020-11-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-4686	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.798	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 4.798
	Call Number	UA @ admin @ c:irua:176083			Serial	8177
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	Author	Zhang, T.; Schilling, W.; Khan, S.U.; Ching, H.Y.V.; Lu, C.; Chen, J.; Jaworski, A.; Barcaro, G.; Monti, S.; De Wael, K.; Slabon, A.; Das, S.
	Title	Atomic-level understanding for the enhanced generation of hydrogen peroxide by the introduction of an aryl amino group in polymeric carbon nitrides			Type	A1 Journal article
	Year	2021	Publication	Acs Catalysis	Abbreviated Journal	Acs Catal
	Volume	11	Issue	22	Pages	14087-14101
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Heterogeneous catalysts are often & ldquo;black boxes & rdquo; due to the insufficient understanding of the detailed mechanisms at the catalytic sites. An atomic-level elucidation of the processes taking place in those regions is, thus, mandatory to produce robust and selective heterogeneous catalysts. We have improved the description of the whole reactive scenario for polymeric carbon nitrides (PCN) by combining atomic-level characterizations with magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy, classical reactive molecular dynamics (RMD) simulations, and quantum chemistry (QC) calculations. We disclose the structure & minus;property relationships of an ad hoc modified PCN by inserting an aryl amino group that turned out to be very efficient for the production of H2O2. The main advancement of this work is the development of a difluoromethylene-substituted aryl amino PCN to generate H2O2 at a rate of 2.0 mM & middot;h & minus;1 under the irradiation of household blue LEDs and the identification of possible active catalytic sites with the aid of 15N and 19F MAS solid-state NMR without using any expensive labeling reagent. RMD simulations and QC calculations confirm and further extend the experimental descriptions by revealing the role and locations of the identified functionalities, namely, NH linkers, & minus;NH2 terminal groups, and difluoromethylene units, reactants, and products. <comment>Superscript/Subscript Available</comment
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000758012900020	Publication Date	2021-11-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2155-5435	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	10.614	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 10.614
	Call Number	UA @ admin @ c:irua:187276			Serial	7534
Permanent link to this record



	Author	Thiruvottriyur Shanmugam, S.; Van Echelpoel, R.; Boeye, G.; Eliaerts, J.; Samanipour, M.; Ching, H.Y.V.; Florea, A.; Van Doorslaer, S.; Van Durme, F.; Samyn, N.; Parrilla, M.; De Wael, K.
	Title	Towards developing a screening strategy for ecstasy : revealing the electrochemical profile			Type	A1 Journal article
	Year	2021	Publication	Chemelectrochem	Abbreviated Journal	Chemelectrochem
	Volume	8	Issue	24	Pages	4826-4834
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	This article describes the development of an electrochemical screening strategy for 3,4-methylenedioxymethamphetamine (MDMA), the regular psychoactive compound in ecstasy (XTC) pills. We have investigated the specific electrochemical profile of MDMA and its electro-oxidation mechanisms at disposable graphite screen-printed electrodes. We have proved that the formation of a radical cation and subsequent reactions are indeed responsible for the electrode surface passivation, as evidenced by using electron paramagnetic resonance spectroscopy and electrochemistry. Thereafter, pure cutting agents and MDMA as well as simulated binary mixtures of compounds with MDMA were subjected to square wave voltammetry at pH 7 to understand the characteristic electrochemical profile. An additional measurement at pH 12 was able to resolve false positives and negatives occurring at pH 7. Finally, validation of the screening strategy was done by measuring a set of ecstasy street samples. Overall, our proposed electrochemical screening strategy has been demonstrated for the rapid, sensitive, and selective detection of MDMA, resolving most of the false positives and negatives given by the traditional Marquis color tests, thus exhibiting remarkable promises for the on-site screening of MDMA.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000735883700020	Publication Date	2021-12-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2196-0216	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.136	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.136
	Call Number	UA @ admin @ c:irua:184371			Serial	8680
Permanent link to this record



	Author	Lybaert, J.; Trashin, S.; Maes, B.U.W.; De Wael, K.; Abbaspour Tehrani, K.
	Title	Cooperative electrocatalytic and chemoselective alcohol oxidation by Shvo's catalyst			Type	A1 Journal article
	Year	2017	Publication	Advanced synthesis and catalysis	Abbreviated Journal	Adv Synth Catal
	Volume	359	Issue	6	Pages	919-925
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
	Abstract	A new electrocatalytic conversion of alcohols to ketones and aldehydes was developed based on an electrochemical study of Shvos complex. The oxidation of secondary alcohols was efficiently performed under mild conditions using a catalytic amount of Shvos catalyst, in combination with a sub-stoichiometric amount of 2,6-dimethoxy-1,4- benzoquinone in N,N-dimethylformamide at 80 8C. The hydroquinone thus formed is continuously reoxidized with the aid of an electrochemical device. Excellent yields for different ketones, aromatic as well as aliphatic and a,b-unsaturated ketones, are obtained. In addition, chemoselectivity towards oxidation of the secondary alcohol is achieved when converting vicinal diols such as 1,2-octanediol and 1,2-decanediol.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000397584000003	Publication Date	2017-01-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1615-4150; 1615-4169	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.646	Times cited	4	Open Access
	Notes	; This work was financially supported by the University of Antwerp (BOF), the Research Foundation – Flanders (FWO) and the Hercules Foundation. ;			Approved	Most recent IF: 5.646
	Call Number	UA @ admin @ c:irua:139795			Serial	5559
Permanent link to this record



	Author	Lybaert, J.; Maes, B.U.W.; Tehrani, K.A.; De Wael, K.
	Title	The electrochemistry of tetrapropylammonium perruthenate, its role in the oxidation of primary alcohols and its potential for electrochemical recycling			Type	A1 Journal article
	Year	2015	Publication	Electrochimica acta	Abbreviated Journal	Electrochim Acta
	Volume	182	Issue		Pages	693-698
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
	Abstract	The search for strategies aiming at more sustainable (oxidation) reactions has led to the application of electrochemistry for recycling the spent catalyst. In this work, an electrochemical study of the tetrapropylammonium perruthenate catalyst (TPAP) and its activity towards a primary alcohol, n-butanol, has been carried out as well as a control study with tert-butanol. The redox chemistry of TPAP and the transition between the perruthenate anion and ruthenium tetroxide in a non-aqueous solvent have been, for the first time, investigated in depth. The oxidation reaction of n-butanol in the presence of TPAP has been electrochemically elucidated by performing potentiostatic experiments and registration of the corresponding oxidation current. Furthermore, it was shown that, by applying a specific potential, the reoxidized TPAP is able to oxidize/convert the primary alcohol, paving the way for practical applications using TPAP in electrochemical synthesis. The conversion of n-butanol into n-butanal was proven by the use of GC-MS.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000365075800084	Publication Date	2015-09-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-4686	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.798	Times cited	2	Open Access
	Notes	; ;			Approved	Most recent IF: 4.798; 2015 IF: 4.504
	Call Number	UA @ admin @ c:irua:127676			Serial	5599
Permanent link to this record



	Author	Lybaert, J.; Tehrani, K.A.; De Wael, K.
	Title	Mediated electrolysis of vicinal diols by neocuproine palladium catalysts			Type	A1 Journal article
	Year	2017	Publication	Electrochimica acta	Abbreviated Journal	Electrochim Acta
	Volume	247	Issue		Pages	685-691
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
	Abstract	Synthetic electrochemistry agrees well with the principles of sustainable chemistry, therefore it is considered as a more environmentally friendly approach than some current synthetic methods Here, we present a new strategy for the chemoselective oxidation of vicinal diols, viz. the integration of neocuproine palladium catalysts and electrosynthesis. Benzoquinones are used as an effective mediator as the reduced species (hydroquinones) can be easily reoxidized at relative low potentials at an electrode surface. NeocuproinePd(OAc)2 efficiently works as a catalyst in an electrolysis reaction for vicinal diols at room temperature. This is a remarkable observation given the fact that aerobic oxidation reactions of alcohols typically need a more complex catalyst, i.e. [neocuproinePdOAc]2[OTf]2. In this article we describe the optimization of the electrolysis conditions for the neocuproinePd(OAc)2 catalyst to selectively oxidize diols. The suggested approach leads to conversion of alcohols with high yields and provides an interesting alternative to perform oxidation reactions under mild conditions by the aid of electrochemistry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000408582300072	Publication Date	2017-07-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-4686	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.798	Times cited		Open Access
	Notes	; ;			Approved	Most recent IF: 4.798
	Call Number	UA @ admin @ c:irua:144118			Serial	5706
Permanent link to this record



	Author	De Wael, K.; De Belder, S.; Pilehar, S.; Van Steenberge, G.; Herrebout, W.; Heering, H.A.
	Title	Enzyme-gelatin electrochemical biosensors : scaling down			Type	A1 Journal article
	Year	2012	Publication	Biosensors	Abbreviated Journal
	Volume	2	Issue		Pages	101-113
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Molecular Spectroscopy (MolSpec)
	Abstract	In this article we investigate the possibility of scaling down enzyme-gelatin modified electrodes by spin coating the enzyme-gelatin layer. Special attention is given to the electrochemical behavior of the selected enzymes inside the gelatin matrix. A glassy carbon electrode was used as a substrate to immobilize, in the first instance, horse heart cytochrome c (HHC) in a gelatin matrix. Both a drop dried and a spin coated layer was prepared. On scaling down, a transition from diffusion controlled reactions towards adsorption controlled reactions is observed. Compared to a drop dried electrode, a spin coated electrode showed a more stable electrochemical behavior. Next to HHC, we also incorporated catalase in a spin coated gelatin matrix immobilized on a glassy carbon electrode. By spincoating, highly uniform sub micrometer layers of biocompatible matrices can be constructed. A full electrochemical study and characterization of the modified surfaces has been carried out. It was clear that in the case of catalase, gluteraldehyde addition was needed to prevent leaking of the catalase from the gelatin matrix.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2012-03-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2079-6374	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:96507			Serial	5606
Permanent link to this record



	Author	Horemans, B.; Van Holsbeke, C.; Vos, W.; Darchuk, L.; Novakovic, V.; Fontan, A.C.; de Backer, J.; van Grieken, R.; de Backer, W.; De Wael, K.
	Title	Particle deposition in airways of chronic respiratory patients exposed to an urban aerosol			Type	A1 Journal article
	Year	2012	Publication	Environmental science and technology	Abbreviated Journal	Environ Sci Technol
	Volume	46	Issue	21	Pages	12162-12169
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
	Abstract	Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for chronic respiratory patients (CRP). Although air quality surveys can be detailed, the obtained information is not always useful to evaluate human health effects. This paper presents a novel approach to estimate particle deposition rates in airways of CRP, based on real air pollution data. By combining computational fluid dynamics with physical-chemical characteristics of particulate pollution, deposition rates are estimated for particles of different toxicological relevance, that is, minerals, iron oxides, sea salts, ammonium salts, and carbonaceous particles. Also, it enables some qualitative evaluation of the spatial, temporal, and patient specific effects on the particle dose upon exposure to the urban atmosphere. Results show how heavy traffic conditions increases the deposition of anthropogenic particles in the trachea and lungs of respiratory patients (here, +0.28 and +1.5 μg·h1, respectively). In addition, local and synoptic meteorological conditions were found to have a strong effect on the overall dose. However, the pathology and age of the patient was found to be more crucial, with highest deposition rates for toxic particles in adults with a mild anomaly, followed by mild asthmatic children and adults with severe respiratory dysfunctions (7, 5, and 3 μg·h1, respectively).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Easton, Pa	Editor
	Language		Wos	000310665000082	Publication Date	2012-10-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-936X;1520-5851;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.198	Times cited	5	Open Access
	Notes	; We are grateful for the financial support of n.v. Vooruitzicht. Furthermore, co-workers at the environmental analysis research group are acknowledged for their help in the fieldwork. ;			Approved	Most recent IF: 6.198; 2012 IF: 5.257
	Call Number	UA @ lucian @ c:irua:101411			Serial	2557
Permanent link to this record



	Author	Krupińska, B.; Worobiec, A.; Rotondo, G.G.; Novaković, V.; Kontozova, V.; Ro, C.-U.; Van Grieken, R.; De Wael, K.
	Title	Assessment of the air quality (NO₂, SO₂, O₃ and particulate matter) in the Plantin-Moretus Museum/Print Room in Antwerp, Belgium, in different seasons of the year			Type	A1 Journal article
	Year	2012	Publication	Microchemical journal	Abbreviated Journal	Microchem J
	Volume	102	Issue	1	Pages	49-53
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
	Abstract	The Plantin-Moretus Museum/Print Room in Antwerp, Belgium, gathers one of the most precious collections of typographical material and old printed books in the world. Rich decorations of this former printing-house and the history of the building itself underline its uniqueness. The cultural heritage (CH) objects collected in the museum, in particular books and manuscripts are vulnerable to the atmospheric pollution and can be irreversibly damaged. To assess the air quality inside the museum, four consecutive sampling campaigns were performed in each season of the year. The gas monitoring of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) was carried out outside the building, in galleries and in showcases by means of using diffusive samplers. The particulate matter (PM) was collected in bulk form and as single particles and then analysed with use of energy dispersive X-ray fluorescence (EDXRF) and electron probe micro-analyser (EPMA), respectively. The museum complex turned out to show good protection against gaseous pollutants, especially SO2 and O3. The concentrations of these pollutants were significantly reduced inside the building in comparison to the outdoor ones. Similar protective character of the museum complex was established in case of the coarse fraction of PM; however with some limitations. Single particle analysis showed that the relative abundance of carbon-rich particles inside the museum was greater than outside. Moreover, these particles contributed more to the fine fraction of PM than to the coarse fraction. Therefore, for better preservation of cultural heritage, special attention should be paid to the small particles and their distribution within the museum.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301559100007	Publication Date	2011-11-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0026-265x; 0026-265x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.034	Times cited	25	Open Access
	Notes	; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ;			Approved	Most recent IF: 3.034; 2012 IF: 2.879
	Call Number	UA @ admin @ c:irua:94466			Serial	5483
Permanent link to this record



	Author	Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K.
	Title	Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb₂Sb₂O₇Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments			Type	A1 Journal article
	Year	2020	Publication	Chemistry Of Materials	Abbreviated Journal	Chem Mater
	Volume	32	Issue	7	Pages	2863-2873
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000526394000016	Publication Date	2020-04-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0897-4756	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.6	Times cited	8	Open Access	OpenAccess
	Notes	Universiteit Antwerpen; Belgian Federal Science Policy Office;			Approved	Most recent IF: 8.6; 2020 IF: 9.466
	Call Number	EMAT @ emat @c:irua:168819			Serial	6363
Permanent link to this record



	Author	Pilehvar, S.; Dierckx, T.; Blust, R.; Breugelmans, T.; De Wael, K.
	Title	An electrochemical impedimetric aptasensing platform for sensitive and selective detection of small molecules such as chloramphenicol			Type	A1 Journal article
	Year	2014	Publication	Sensors	Abbreviated Journal	Sensors-Basel
	Volume	14	Issue	7	Pages	12059-12069
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
	Abstract	We report on the aptadetection of chloramphenicol (CAP) using electrochemical impedance spectroscopy. The detection principle is based on the changes of the interfacial properties of the electrode after the interaction of the ssDNA aptamers with the target molecules. The electrode surface is partially blocked due to the formation of the aptamer-CAP complex, resulting in an increase of the interfacial electron-transfer resistance of the redox probe detected by electrochemical impedance spectroscopy or cyclic voltammetry. We observed that the ratio of polarization resistance had a linear relationship with the concentrations of CAP in the range of 1.76127 nM, and a detection limit of 1.76 nM was obtained. The covalent binding of CAP-aptamer on the electrode surface combined with the unique properties of aptamers and impedimetric transduction leads to the development of a stable and sensitive electrochemical aptasensor for CAP.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000340035700041	Publication Date	2014-07-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1424-8220	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.677	Times cited	34	Open Access
	Notes	; We are thankful to UA-DOCPRO and UA-BOFACA for financial support. ;			Approved	Most recent IF: 2.677; 2014 IF: 2.245
	Call Number	UA @ admin @ c:irua:117845			Serial	5592
Permanent link to this record



	Author	Pauwels, D.; Ching, H.Y.V.; Samanipour, M.; Neukermans, S.; Hereijgers, J.; Van Doorslaer, S.; De Wael, K.; Breugelmans, T.
	Title	Identifying intermediates in the reductive intramolecular cyclisation of allyl 2-bromobenzyl ether by an improved electron paramagnetic resonance spectroelectrochemical electrode design combined with density functional theory calculations			Type	A1 Journal article
	Year	2018	Publication	Electrochimica acta	Abbreviated Journal	Electrochim Acta
	Volume	271	Issue	271	Pages	10-18
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
	Abstract	The electrochemical activation of C-X bonds requires very negative electrode potentials. Lowering the overpotentials and increasing the catalytic activity requires intensive electrocatalytic research. A profound understanding of the reaction mechanism and the influence of the electrocatalyst allows optimal tuning of the electrocatalyst. This can be achieved by combining electrochemical techniques with electron paramagnetic resonance (EPR) spectroscopy. Although this was introduced in the mid-twentieth century, the application of this combined approach in electrocatalytic research is underexploited. Several reasons can be listed, such as the limited availability of EPR instrumentation and electrochemical devices for such in situ experiments. In this work, a simple and inexpensive construction adapted for in situ EPR electrocatalytic research is proposed. The proof of concept is provided by studying a model reaction, namely the reductive cyclisation of allyl 2-bromobenzyl ether which has interesting industrial applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000430369800002	Publication Date	2018-03-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-4686	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.798	Times cited	2	Open Access
	Notes	; The authors would like to thank Melissa Van Landeghem for her assistance with the experimental work and analysis of the data. Jonas Hereijgers greatly acknowledges the Research Foundation Flanders (FWO) for support through a Post-Doctoral grant (12Q8817N). H.Y. Vincent Ching gratefully acknowledges the University of Antwerp for a Post-Doctoral grant. Sabine Van Doorslaer and Tom Breugelmans acknowledge the FWO for research funding (research grant G093317N). ;			Approved	Most recent IF: 4.798
	Call Number	UA @ admin @ c:irua:150463			Serial	5652
Permanent link to this record



	Author	Mendonça, C.D.; Rahemi, V.; Hereijgers, J.; Breugelmans, T.; Machado, S.A.S.; De Wael, K.
	Title	Integration of a photoelectrochemical cell in a flow system for quantification of 4-aminophenol with titanium dioxide			Type	A1 Journal article
	Year	2020	Publication	Electrochemistry Communications	Abbreviated Journal	Electrochem Commun
	Volume	117	Issue		Pages	106767-5
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
	Abstract	The photoelectrochemical quantification of phenolic compounds such as hydroquinone (HQ) and 4-aminophenol (4-AP) is accomplished by integrating a photoelectrochemical cell into a flow injection analysis (FIA) setup. It is a well-known fact that during the electroanalysis of phenolic compounds, the electrode surface is susceptible to poisoning. However, electrode fouling can be reduced significantly by using the FIA system with periodic washing of the electrode. Reactive oxygen species (ROS), which are generated on the surface of TiO2 under UV light, can oxidize phenolic compounds such as 4-AP. The oxidized form of 4-AP is reduced back at the electrode surface, generating a measurable signal proportional to its concentration. The factors influencing the perfor-mance of the sensor, such as flow rate, applied potential for back reduction and pH, are investigated in detail. In the concentration range 0.0125-1.0 mu M, a linear correlation between the photocurrent and the concentration of 4-AP was observed with a sensitivity of 0.6 A M-1 cm(-2) and a limit of detection of 18 nM. A straightforward analytical methodology for the on-site, highly sensitive and low-cost quantification of phenolic compounds is presented, based on the use of TiO2 in a photoelectrochemical flow cell.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000552618700004	Publication Date	2020-06-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1388-2481; 1873-1902	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.4	Times cited	1	Open Access
	Notes	; The authors thank FAPESP funding for the fellowship to Camila D. Mendonca (Grant #2018/13724-0) and FWO funding (grant 12T4219N and 28761) for the postdoctoral fellowship to Dr. Vanoushe Rahemi and Dr. Jonas Hereijgers. ;			Approved	Most recent IF: 5.4; 2020 IF: 4.396
	Call Number	UA @ admin @ c:irua:169924			Serial	6547
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	Author	Drăgan, A.-M.; Parrilla, M.; Feier, B.; Oprean, R.; Cristea, C.; De Wael, K.
	Title	Analytical techniques for the detection of amphetamine-type substances in different matrices : a comprehensive review			Type	A1 Journal article
	Year	2021	Publication	Trac-Trends In Analytical Chemistry	Abbreviated Journal	Trac-Trend Anal Chem
	Volume	145	Issue		Pages	116447
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	This current review focuses on contributions to amphetamine-type substances (ATS) analysis. This type of synthetic illicit drugs has been increasingly present worldwide reaching 5% of the market on illicit drugs in 2019. The increment of their production in many clandestine laboratories and easy distribution among society are two of the main concerns towards the battle against synthetic drugs. Therefore, the first part of this review details the classification and mechanism of action of ATS in the human body. Second, the pharmacological and toxicological effects of ATS on human health are described to motivate the need of early detection of ATS. Subsequently, the most used laboratory-based and portable methods are presented and critically discussed along the review. Finally, a careful discussion on the advantages and disadvantages of portable techniques employed on the field are addressed as potential tools for on-site ATS detection by law enforcement officers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000723747000009	Publication Date	2021-09-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0165-9936; 1879-3142	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.442	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 8.442
	Call Number	UA @ admin @ c:irua:183268			Serial	7460
Permanent link to this record



	Author	Trashin, S.; Morales-Yánez, F.; Thiruvottriyur Shanmugam, S.; Paredis, L.; Carrión, E.N.; Sariego, I.; Muyldermans, S.; Polman, K.; Gorun, S.M.; De Wael, K.
	Title	Nanobody-based immunosensor detection enhanced by photocatalytic-electrochemical redox cycling			Type	A1 Journal article
	Year	2021	Publication	Analytical Chemistry	Abbreviated Journal	Anal Chem
	Volume	93	Issue	40	Pages	13606-13614
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Detection of antigenic biomarkers present in trace amounts is of crucial importance for medical diagnosis. A parasitic disease, human toxocariasis, lacks an adequate diagnostic method despite its worldwide occurrence. The currently used serology tests may stay positive even years after a possibly unnoticed infection, whereas the direct detection of a re-infection or a still active infection remains a diagnostic challenge due to the low concentration of circulating parasitic antigens. We report a time-efficient sandwich immunosensor using small recombinant single-domain antibodies (nanobodies) derived from camelid heavy-chain antibodies specific to Toxocara canis antigens. An enhanced sensitivity to pg/mL levels is achieved by using a redox cycle consisting of a photocatalytic oxidation and electrochemical reduction steps. The photocatalytic oxidation is achieved by a photosensitizer generating singlet oxygen (1O2) that, in turn, readily reacts with p-nitrophenol enzymatically produced under alkaline conditions. The photooxidation produces benzoquinone that is electrochemically reduced to hydroquinone, generating an amperometric response. The light-driven process could be easily separated from the background, thus making amperometric detection more reliable. The proposed method for detection of the toxocariasis antigen marker shows superior performances compared to other detection schemes with the same nanobodies and outperforms by at least two orders of magnitude the assays based on regular antibodies, thus suggesting new opportunities for electrochemical immunoassays of challenging low levels of antigens.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000708550500025	Publication Date	2021-09-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:181795			Serial	8290
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	Author	Ortiz-Aguayo, D.; De Wael, K.; del Valle, M.
	Title	Voltammetric sensing using an array of modified SPCE coupled with machine learning strategies for the improved identification of opioids in presence of cutting agents			Type	A1 Journal article
	Year	2021	Publication	Journal Of Electroanalytical Chemistry	Abbreviated Journal	J Electroanal Chem
	Volume	902	Issue		Pages	115770
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	This work reports the use of modified screen-printed carbon electrodes (SPCEs) for the identification of three drugs of abuse and two habitual cutting agents, caffeine and paracetamol, combining voltammetric sensing and chemometrics. In order to achieve this goal, codeine, heroin and morphine were subjected to Square Wave Voltammetry (SWV) at pH 7, in order to elucidate their electrochemical fingerprints. The optimized SPCEs electrode array, which have a differentiated response for the three oxidizable compounds, was derived from Carbon, Prussian blue, Cobalt (II) phthalocyanine, Copper (II) oxide, Polypyrrole and Palladium nanoparticles ink-modified carbon electrodes. Finally, Principal Component Analysis (PCA) coupled with Silhouette parameter assessment was used to select the most suitable combination of sensors for identification of drugs of abuse in presence of cutting agents.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000714415500006	Publication Date	2021-10-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1572-6657; 1873-2569	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.012	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.012
	Call Number	UA @ admin @ c:irua:184018			Serial	8745
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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	Anaf, W.; Schalm, O.; Janssens, K.; De Wael, K.
	Title	Understanding the (in)stability of semiconductor pigments by a thermodynamic approach			Type	A1 Journal article
	Year	2015	Publication	Dyes and pigments	Abbreviated Journal	Dyes Pigments
	Volume	113	Issue		Pages	409-415
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
	Abstract	Several artists pigments are semiconductors. Some of these materials appear stable over time, whereas others already show remarkable signs of degradation after limited time periods. The (in)stability of these pigments can be understood using a thermodynamic approach. For several pigment-related materials, the thermodynamic oxidation and reduction potential (ϕox and ϕred) were determined and evaluated considering the absolute energy positions of the valence and conduction band edges and the water redox potentials. The positions of ϕox and ϕred can be used in a fast screening of the stability of semiconductor pigments towards photoinduced corrosion in an aqueous/humid environment. This theoretical approach corresponds well with experimental data on pigment permanence and degradation phenomena found in literature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000346543200052	Publication Date	2014-09-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0143-7208	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.473	Times cited	14	Open Access
	Notes	; The authors acknowledge the funding from the Belspo S2-ART project (Belgian Federal Government) SD/RI/04A. ;			Approved	Most recent IF: 3.473; 2015 IF: 3.966
	Call Number	UA @ admin @ c:irua:118875			Serial	5885
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	Author	Wuyts, K.; Hofman, J.; van Wittenberghe, S.; Nuyts, G.; De Wael, K.; Samson, R.
	Title	A new opportunity for biomagnetic monitoring of particulate pollution in an urban environment using tree branches			Type	A1 Journal article
	Year	2018	Publication	Atmospheric environment : an international journal	Abbreviated Journal	Atmos Environ
	Volume	190	Issue	190	Pages	177-187
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Environmental magnetism, and the magnetic leaf signal in particular, is amply investigated and applied as proxy for atmospheric particulate matter pollution. In this study, we investigated the magnetic signal of annual segments of tree branches, and the composition of particles deposited hereon. Branches are, contrary to leaves of deciduous trees, available during leaf-off seasons and exposed to air pollution year-round. We examined the intra- and inter-tree variation in saturation isothermal remanent magnetization (SIRM) of branch internodes of London plane (Platanus x aeerifolia Willd.) trees in an urban environment. The branch SIRM, normalized by surface area, ranged from 18 to 650 x 10(-6) angstrom; the median amounted to 106 x 10(-6) angstrom. Most of the branch magnetic signal was attributed to the epidermis or bark, and the presence of metal-containing particles on the branch surfaces was confirmed by SEM-EDX. The location of the trees and the height, the depth in the crown and the age of the branches significantly influenced the branch SIRM. The median branch SIRM was up to 135% higher near a busy ring road than in quiet environments (city park and quiet street canyon), and was linked to the presence of Fe-rich particles with co-occurrence of trace metals such as Cr, Cu, Zn and Mn on the branch surface. Within the tree crowns, the branch SIRM generally decreased with increasing height, and was 22% higher in the interior than at the periphery of the crowns. Within the branches, the SIRM increased with each year of exposure, but did not relate to year-to-year variation in particle concentrations due to branch surface changes (epidermis shedding). Our results provide indications that branches can be a valuable alternative for biomagnetic monitoring of particulate pollution, but intra-tree variability in branch SIRM can be substantial due to the branch's location in the tree and branch age.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000444659400017	Publication Date	2018-07-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1352-2310	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.629	Times cited	3	Open Access
	Notes	; We would like to thank the city council services of the city of Antwerp for their logistical support. We are grateful to Ana Castanheiro and Leen Van Ham for laboratory and SEM assistance. JH is supported as postdoctoral fellow of the Research Foundation Flanders (FWO; 12I4816N) and SVW is supported by a Marie Sklodowska-Curie Individual Fellowship under the grant agreement no 701815 FLUOPHOT. ;			Approved	Most recent IF: 3.629
	Call Number	UA @ admin @ c:irua:153607			Serial	5454
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	Author	Krupińska, B.; Van Grieken, R.; De Wael, K.
	Title	Air quality monitoring in a museum for preventive conservation : results of a three-year study in the Plantin-Moretus Museum in Antwerp, Belgium			Type	A1 Journal article
	Year	2013	Publication	Microchemical journal	Abbreviated Journal	Microchem J
	Volume	110	Issue		Pages	350-360
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Through different research projects on air quality in museums, researcher and conservators try identifying various risks of air pollution on materials. The conclusions may be later translated into specific actions for a maximum preservation of the museum collections, a process known as preventive conservation. Air pollution is a particular problem in historical buildings such as museums, because they were not originally built to exhibit and protect art objects in a sustainable way. This article reports on the data and results that were obtained during 10 sampling campaigns, in the period between November 2008 and February 2012 in a museum in Antwerp (Belgium), i.e. Plantin-Moretus Museum/Print Room. Different pollutants were measured inside and outside the museum such as inorganic gases, particulate matter and black carbon. The report specifically addresses environmental factors that may be responsible for damage to the collections present in museums. Thanks to the knowledge about the current situation in the museum, accurate solutions regarding preventive conservation, in general, are suggested.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000326851200051	Publication Date	2013-05-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0026-265x; 0026-265x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.034	Times cited	46	Open Access
	Notes	; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. VMM and Dr. Edward Roekens is acknowledged for sharing the black carbon measurements. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ;			Approved	Most recent IF: 3.034; 2013 IF: 3.583
	Call Number	UA @ admin @ c:irua:108402			Serial	5460
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