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Author Bottari, F.; Blust, R.; De Wael, K. pdf  doi
openurl 
  Title Bio(inspired) strategies for the electro-sensing of β-lactam antibiotics Type A1 Journal article
  Year 2018 Publication Current opinion in electrochemistry Abbreviated Journal  
  Volume 10 Issue 10 Pages 143-148  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The dire previsions of the WHO on the so-called “post-antibiotic era” and the continuous and global rise of anti-microbial resistance, spurs our research community to find better ways to fight these threats. In light of this severe threat to human health many attempts have been made to develop efficient methods to detect antibiotic residues in different streams. The use of electrochemistry seems an inviting approach for on-site and fast monitoring. In this critical review, recent developments in the field of (bio) electro-sensing of 19-lactam antibiotics will be presented, with a focus on aptamers and molecularly imprinted polymers, the two main promises of a new generation of biosensors, yet to be fulfilled.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000442800000022 Publication Date 2018-05-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2451-9103; 2451-9111 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles  
  Impact Factor Times cited 15 Open Access  
  Notes ; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation – Flanders (FWO). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:153744 Serial 5488  
Permanent link to this record
 

 
Author Moro, G.; De Wael, K.; Moretto, L.M. pdf  url
doi  openurl
  Title Challenges in the electrochemical (bio)sensing of non-electroactive food and environmental contaminants Type A1 Journal article
  Year 2019 Publication Current opinion in electrochemistry Abbreviated Journal  
  Volume 16 Issue 16 Pages 57-65  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The electrochemical detection of non-electroactive contaminants can be successfully faced via the use of indirect detection strategies. These strategies can provide sensitive and selective responses often coupled with portable and user-friendly analytical tools. Indirect detection strategies are usually based on the change in the signal of an electroactive probe, induced by the presence of the target molecule at a modified electrode. This critical review aims at addressing the developments in indirect electro-sensing strategies for non-electroactive contaminants in food and environmental analysis in the last years (2017-2019). Emphasis is given to the strategy design, the electrode modifiers used and the feasibility of technological transfer.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000485814400010 Publication Date 2019-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2451-9103; 2451-9111 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 4 Open Access  
  Notes ; ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:159574 Serial 5498  
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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. doi  openurl
  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 (up) 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 Anaf, W.; Horemans, B.; Van Grieken, R.; De Wael, K. pdf  doi
openurl 
  Title Chemical boundary conditions for the classification of aerosol particles using computer controlled electron probe microanalysis Type A1 Journal article
  Year 2012 Publication Talanta : the international journal of pure and applied analytical chemistry Abbreviated Journal Talanta  
  Volume 101 Issue Pages 420-427  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A method for the classification of individual aerosol particles using computer controlled electron probe microanalysis is presented. It is based on chemical boundary conditions (CBC) and enables quick and easy processing of a large set of elemental concentration data (mass%), derived from the X-ray spectra of individual particles. The particles are first classified into five major classes (sea salt related, secondary inorganic, minerals, iron-rich and carbonaceous), after which advanced data mining can be performed by examining the elemental composition of particles within each class into more detail (e.g., by ternary diagrams). The CBC method is validated and evaluated by comparing its results with the output obtained with hierarchical cluster analysis (HCA) for well-known standard particles as well as real aerosol particles collected with a cascade impactor. The CBC method gives reliable results and has a major advantage compared to HCA. CBC is based on boundary conditions that are derived from chemical logical thinking and does not require a translation of a mathematical algorithm output as does HCA. Therefore, the CBC method is more objective and enables comparison between samples without intermediate steps.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000313084400061 Publication Date 2012-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.162 Times cited 3 Open Access  
  Notes ; ; Approved Most recent IF: 4.162; 2012 IF: 3.498  
  Call Number UA @ admin @ c:irua:101336 Serial 5511  
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Author Vanmeert, F.; Hendriks, E.; van der Snickt, G.; Monico, L.; Dik, J.; Janssens, K. doi  openurl
  Title Chemical Mapping by Macroscopic X-ray Powder Diffraction (MA-XRPD) of Van Gogh's Sunflowers : identification of areas with higher degradation risk Type A1 Journal article
  Year 2018 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 57 Issue 25 Pages 7418-7422  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The discoloration rate of chrome yellow (CY), a class of synthetic inorganic pigments (PbCr1-xSxO4) frequently used by Van Gogh and his contemporaries, strongly depends on its sulfate content and on its crystalline structure (either monoclinic or orthorhombic). Macroscopic X-Ray powder diffraction imaging of selected areas on Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam) revealed the presence of two subtypes of CY: the light-fast monoclinic PbCrO4 (LF-CY) and the light-sensitive monoclinic PbCr1-xSxO4 (x approximate to 0.5; LS-CY). The latter was encountered in large parts of the painting (e.g., in the pale-yellow background and the bright-yellow petals, but also in the green stems and flower hearts), thus indicating their higher risk for past or future darkening. Overall, it is present in more than 50% of the CY regions. Preferred orientation of LS-CY allows observation of a significant ordering of the elongated crystallites along the direction of Van Gogh's brush strokes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000434949200023 Publication Date 2018-03-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 10 Open Access  
  Notes ; The authors acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, the GOA Project Solarpaint (University of Antwerp Research Council), and the Interreg Smart*Light project. Raman analyses were performed using the European MOLAB platform, which is financially supported by the Horizon 2020 Programme (IPERION CH Grant 654028). The authors thank the staff of the Van Gogh Museum for their collaboration. ; Approved Most recent IF: 11.994  
  Call Number UA @ admin @ c:irua:153185 Serial 5517  
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Author Monico, L.; Janssens, K.; Cotte, M.; Sorace, L.; Vanmeert, F.; Brunetti, B.G.; Miliani, C. pdf  url
doi  openurl
  Title Chromium speciation methods and infrared spectroscopy for studying the chemical reactivity of lead chromate-based pigments in oil medium Type A1 Journal article
  Year 2016 Publication Microchemical journal T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY Abbreviated Journal Microchem J  
  Volume 124 Issue Pages 272-282  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Environmental factors, such as light, humidity and temperature are triggering agents for the alteration of organic and/or inorganic constituents of oil paintings. The oxidation of the organic material is favored by increasing of relative humidity and temperature, whereas processes involving changes of the oxidation states of a number of inorganic pigments (e.g., vermilion, cadmium yellows, zinc yellows, chrome yellows) are mainly activated by light-exposure. In view of the optimization of the long-term conservation and restoration strategies of paintings it is of relevant interest to establish the consequences of thermal parameters (temperature and relative humidity) on the chemical/photochemical-reactivity and the nature of the alteration products of light sensitive-pigments in oil medium. To this aim here we propose a multi-method analytical approach based on the combination of diffuse reflectance UV-Vis, FTIR, synchrotron radiation (SR)-based micro X-ray fluorescence (mu-XRF)/micro-X-ray absorption neat edge structure ()CANES) and electron paramagnetic resonance (EPR) spectroscopies for studying the effects of different relative humidity conditions before and after light exposure on the reactivity of a series of lead chromate-based pigments [such as PbCrO4 center dot PbO (monoclinic), PbCrO4 (monoclinic) and PbCr0.2S0.8O4 (orthorhombic)] in an oil medium. The investigation of paint models was also compared to that of a late 19th century historical orthorhombic PbCr0.4S0.6O4 oil paint. Diffuse reflectance UV-Vis and FTIR spectroscopies were used to obtain information associated with chromatic changes and the formation of organo-metal degradation products at the paint surface. SR-based Cr K-edge mu-XANES/mu-XRF mapping analysis and EPR spectroscopy were employed in a complementary fashion to determine the amount, nature and distribution of Cr(III) and Cr(V)-based alteration compounds within the paints with micrometric spatial resolution. Under the employed thermal aging conditions, lead(II)-carboxylates and reduced Cr-compounds (in abundance of up to about 35% at the surface) have been identified in the lead chromate-based paints. The tendency of chromates to become reduced increased with increasing moisture levels and was favored for the orthorhombic PbCr0.2S0.8O4 compounds. The redox process gave rise to the formation of Cr(V)-species in relative amount much higher than that was formed in the equivalent paint which was exposed only to light. After light-exposure of the thermally aged paints, compounds ascribable to the oxidation of the organic binder were detected for all the types of pigments. Nevertheless, the previous thermal treatment increased the tendency toward photo-reduction of only the PbCr0.2S0.8O4 pigment. For this light-sensitive compound, the thickness variation of the reduced Cr-rich (ca. 70%) photo-alteration layer with moisture levels could be ascribed to a surface passivation phenomenon that had already occurred before photochemical aging. (C) 2015 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000367755600042 Publication Date 2015-09-12  
  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 23 Open Access  
  Notes ; ; Approved Most recent IF: 3.034  
  Call Number UA @ admin @ c:irua:131099 Serial 5519  
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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. url  doi
openurl 
  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 (up) 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. doi  openurl
  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 (up) 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 Cagno, S.; Janssens, K.; Mendera, M. doi  openurl
  Title Compositional analysis of Tuscan glass samples: in search of raw materials fingerprints Type A1 Journal article
  Year 2008 Publication Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 391 Issue 4 Pages 1389-1395  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700035 Publication Date 2008-02-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 26 Open Access  
  Notes Approved Most recent IF: 3.431; 2008 IF: 3.328  
  Call Number UA @ admin @ c:irua:69320 Serial 5545  
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Author Hellar-Kihampa, H.; Potgieter-Vermaak, S.; De Wael, K.; Lugwisha, E.; van Espen, P.; Van Grieken, R. doi  openurl
  Title Concentration profiles of metal contaminants in fluvial sediments of a rural-urban drainage basin in Tanzania Type A1 Journal article
  Year 2014 Publication International journal of environmental analytical chemistry Abbreviated Journal Int J Environ An Ch  
  Volume 94 Issue 1 Pages 77-98  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract This study investigated concentration profiles of trace, rare earth and platinum group metals in fluvial sediments from the Pangani river basin (43,650 km2), one of the largest river basins in Tanzania, to assess its environmental quality. Sediment samples were collected in two distinct seasons from 12 representative sites of diverse land-use practices and characterised by ICP-MS after optimised microwave digestion. Ecological risks were assessed by evaluation of pollution index and comparison with legislated sediment quality guidelines (SQG). The results revealed contamination by some trace metals (e.g. Pb, V, Cu, Cr, Ni, Cd, As, Co, Mn and Zn) in concentrations ranging from 0.7 to 2940 mg kg−1, and four rare earth elements (Y, Ce, Nd, Yb) in concentrations ranging from 0.9 (Yb) to 500 mg kg−1 dry weight (Ce), which significantly exceeded the estimated background values at some stations. Palladium was the only platinum group element that was detected in quantifiable concentrations (0.33.5 mg kg−1). Concentrations of some trace metals exceeded the SQGs at some localised areas. Principal component analysis and multivariate correlations indicated geochemical characteristics of the area as the major control of metal concentrations and spatial variability. Organic matter and clay contents also played a significant role in metal distributions. Assessment of land-use practices upstream of the sampling locations was used to trace potential anthropogenic sources of metal enrichments, where highest levels were found in areas close to urban centres and agricultural activities. The study provides baseline data for future monitoring programs, and highlights the need for more comprehensive analysis involving a wider spatio-temporal scale and ecotoxicological risk assessment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000329774500007 Publication Date 2013-05-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0306-7319 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.208 Times cited 5 Open Access  
  Notes ; The participants of this research gratefully acknowledge the financial support of the Belgian Development Agency (BTC). The contribution of the Pangani Basin Water Board (PBWB), especially Ms Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns is greatly appreciated. We sincerely acknowledge the assistance of Mr. Elisa Dunstan Kiwelu of Ardhi University, Dar es Salaam, Tanzania in mapping the study area; Mr Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterisation; and Dr Valentine Kayawe Mubiana of the Department of Biology, University of Antwerp in ICP-MS analysis. The contributions of six anonymous reviewers, which greatly improved the manuscript for this paper, are highly appreciated. ; Approved Most recent IF: 1.208; 2014 IF: 1.295  
  Call Number UA @ admin @ c:irua:109234 Serial 5547  
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Author Hamidi-Asl, E.; Daems, D.; De Wael, K.; Van Camp, G.; Nagels, L.J. url  doi
openurl 
  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 (up) 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 Moro, G.; Bottari, F.; Sleegers, N.; Florea, A.; Cowen, T.; Moretto, L.M.; Piletsky, S.; De Wael, K. pdf  doi
openurl 
  Title Conductive imprinted polymers for the direct electrochemical detection of beta-lactam antibiotics: The case of cefquinome Type A1 Journal article
  Year 2019 Publication Sensors and actuators : B : chemical Abbreviated Journal Sensor Actuat B-Chem  
  Volume 297 Issue 297 Pages 126786  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A biomimetic sensor for cefquinome (CFQ) was designed at multi-walled carbon nanotubes modified graphite screen-printed electrodes (MWCNTs-G-SPEs) as a proof-of-concept for the creation of a sensors array for beta-lactam antibiotics detection in milk. The sensitive and selective detection of antibiotic residues in food and environment is a fundamental step in the elaboration of prevention strategies to fight the insurgence of antimicrobial resistance (AMR) as recommended by authorities around the world (EU, WHO, FDA). The detection strategy is based on the characteristic electrochemical fingerprint of the target antibiotic cefquinome. A conducive electropolymerized molecularly imprinted polymer (MIP) coupled with MWCNTs was found to be the optimal electrode modifier, able to provide an increased selectivity and sensitivity for CFQ detection. The design of CFQ-MIP was facilitated by the rational selection of the monomer, 4-aminobenzoic acid (4-ABA). The electropolymerization process of 4-ABA have not been fully elucidated yet; for this reason a thorough study and optimization of electropolymerization conditions was performed to obtain a conducive and stable poly(4-ABA) film. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and cyclic voltammetry (CV). CFQ-MIP were synthesized at MWCNT-G-SPEs by electropolyrnerization in pH approximate to 1 (0.1 M sulphuric acid) with a monomer:template ratio of 5:1. Two different analytical protocols were tested (single and double step detection) to minimize unspecific adsorptions and improve the sensitivity. Under optimal conditions, the lowest CFQ concentration detectable by square wave voltammetry (SWV) at the modified sensor was 50 nM in 0.1 M phosphate buffer pH 2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000478562700020 Publication Date 2019-07-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-4005 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.401 Times cited 4 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. This work was also supported by FWO. ; Approved Most recent IF: 5.401  
  Call Number UA @ admin @ c:irua:161777 Serial 5549  
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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. doi  openurl
  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 (up) 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. doi  openurl
  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 (up) 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. doi  openurl
  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 (up) 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 Hirayama, A.; Abe, Y.; van Loon, A.; De Keyser, N.; Noble, P.; Vanmeert, F.; Janssens, K.; Tantrakarn, K.; Taniguchi, K.; Nakai, I. pdf  doi
openurl 
  Title Development of a new portable X-ray powder diffractometer and its demonstration to on-site analysis of two selected old master paintings from the Rijksmuseum Type A1 Journal article
  Year 2018 Publication Microchemical journal Abbreviated Journal Microchem J  
  Volume 138 Issue 138 Pages 266-272  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A portable X-ray powder diffractometer (p-XRD) PT-APXRD III has been developed for onsite analysis of paintings and archaeological samples. By using a Cu anode X-ray tube and a silicon drift diode (SDD) detector, diffraction patterns with a high signalnoise (S/N) ratio can be recorded. The X-ray tube can be operated at a maximum voltage of 60 kV, which makes it possible to simultaneously record X-ray fluorescence spectra up to the high-energy region. The total weight of this instrument is 16 kg, which can be carried anywhere and the goniometer unit (5.6 kg) can be placed on a tripod for analysis of mural paintings. We brought the instrument to the Rijksmuseum in the Netherlands to examine its applicability for the analysis of oil paintings. We successfully analyzed two seventeenthcentury oil paintings by Johannes Vermeer and Jan Davidsz de Heem (copy after). Ultramarine blue, leadtin yellow type I, and Naples yellow were identified from the diffraction patterns, demonstrating the high practicality of this instrument. Furthermore, it was found from the SEM-EDX analysis of a paint cross section that the yellow pigment was applied in separate layers rather than being mixed. This diffractometer will be commercially available in the near future and will have many applications in the field of material analysis. (C) 2018 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000428103000030 Publication Date 2018-01-04  
  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 2 Open Access  
  Notes ; This research was conducted with the support of the JSPS (Tokyo, Japan)-FWO (Brussels, Belgium) bilateral exchange project. ; Approved Most recent IF: 3.034  
  Call Number UA @ admin @ c:irua:151565 Serial 5575  
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Author Elia, A.; De Wael, K.; Dowsett, M.; Adriaens, A. doi  openurl
  Title Electrochemical deposition of a copper carboxylate layer on copper as potential corrosion inhibitor Type A1 Journal article
  Year 2011 Publication Journal of solid state electrochemistry Abbreviated Journal J Solid State Electr  
  Volume 16 Issue 1 Pages 143-148  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Carboxylic acids and sodium carboxylates are used to protect metals against aqueous and atmospheric corrosion. In this paper, we describe the application of a layer of copper carboxylate on the surface of a copper electrode by means of cyclic voltammetry technique and tests which measure the corresponding resistance to aqueous corrosion. Unlike the soaking process, which also forms a film on the surface, the use of cyclic voltammetry allows one to follow the deposition process of the copper carboxylates onto the electrode. The modified electrodes have been characterised with infrared spectroscopy. In addition, the corrosion resistance of the film has been investigated using polarisation resistance and Tafel plot measurements.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000298651700018 Publication Date 2011-01-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1432-8488 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.316 Times cited 8 Open Access  
  Notes ; Authors would like to acknowledge the Research Foundation-Flanders (FWO) for funding assistance (A. Elia is a FWO aspirant) and V. Vermeersch and S. Van Vlierberghe (Ghent University, Polymer Chemistry and Biomaterials Research Group) for the FTIR-ATR measurements. ; Approved Most recent IF: 2.316; 2011 IF: 2.131  
  Call Number UA @ admin @ c:irua:89618 Serial 5588  
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Author De Wael, K.; Bashir, Q.; van Vlierberghe, S.; Dubruel, P.; Heering, H.A.; Adriaens, A. pdf  doi
openurl 
  Title Electrochemical determination of hydrogen peroxide with cytochrome c peroxidase and horse heart cytochrome c entrapped in a gelatin hydrogel Type A1 Journal article
  Year 2012 Publication Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry Abbreviated Journal Bioelectrochemistry  
  Volume 83 Issue Pages 15-18  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A novel and versatile method, based on a membrane-free enzyme electrode in which both the enzyme and a mediator protein are entrapped in a gelatine hydrogel was developed for the fabrication of biosensors. As a proof of principle, we prepared a hydrogen peroxide biosensor by successfully entrapping both horse heart cytochrome c (HHC) and Saccharomyces cerevisae cytochrome c peroxidase (CCP) in a gelatin matrix which is immobilized on a gold electrode. This electrode was first pretreated with 6-mercaptohexanol. The biosensor displayed a rapid response and an expanded linear response range from 0 to 0.3 mM (R = 0.987) with a detection limit of 1 × 10− 5 M in a HEPES buffer solution (pH 7.0). This method of encapsulation is now further investigated for industrial biosensor applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297962500003 Publication Date 2011-08-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1567-5394 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.346 Times cited 31 Open Access  
  Notes ; Karolien De Wael is grateful to the Research Foundation-Flanders (FWO, Belgium) for her postdoctoral fellowship. ; Approved Most recent IF: 3.346; 2012 IF: 3.947  
  Call Number UA @ admin @ c:irua:92067 Serial 5589  
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Author Trashin, S.; De Jong, M.; Luyckx, E.; Dewilde, S.; De Wael, K. url  doi
openurl 
  Title Electrochemical evidence for neuroglobin activity on NO at physiological concentrations Type A1 Journal article
  Year 2016 Publication Journal of biological chemistry Abbreviated Journal J Biol Chem  
  Volume 291 Issue 36 Pages 18959-18966  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The true function of neuroglobin (Ngb) and, particularly, human Ngb (NGB) has been under debate since its discovery 15 years ago. It has been expected to play a role in oxygen binding/supply, but a variety of other functions have been put forward, including NO dioxygenase activity. However, in vitro studies that could unravel these potential roles have been hampered by the lack of an Ngb-specific reductase. In this work, we used electrochemical measurements to investigate the role of an intermittent internal disulfide bridge in determining NO oxidation kinetics at physiological NO concentrations. The use of a polarized electrode to efficiently interconvert the ferric (Fe3+) and ferrous (Fe2+) forms of an immobilized NGB showed that the disulfide bridge both defines the kinetics of NO dioxygenase activity and regulates appearance of the free ferrous deoxy-NGB, which is the redox active form of the protein in contrast to oxy-NGB. Our studies further identified a role for the distal histidine, interacting with the hexacoordinated iron atom of the heme, in oxidation kinetics. These findings may be relevant in vivo, for example in blocking apoptosis by reduction of ferric cytochrome c, and gentle tuning of NO concentration in the tissues.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000383242300031 Publication Date 2016-07-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9258; 1083-351x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.125 Times cited 11 Open Access  
  Notes ; This work was supported by Fonds Wetenschappelijk Onderzoek (FWO) Grant G.0687.13 and Universiteit Antwerpen GOA BOF 28312. The authors declare that they have no conflicts of interest with the contents of this article. ; Approved Most recent IF: 4.125  
  Call Number UA @ admin @ c:irua:134340 Serial 5590  
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Author De Jong, M.; Sleegers, N.; Kim, J.; Van Durme, F.; Samyn, N.; Wang, J.; De Wael, K. url  doi
openurl 
  Title Electrochemical fingerprint of street samples for fast on-site screening of cocaine in seized drug powders Type A1 Journal article
  Year 2016 Publication Chemical science Abbreviated Journal Chem Sci  
  Volume Issue Pages 1-7  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract We report on a wearable fingertip sensor for on-the-spot identification of cocaine and its cutting agents in street samples. Traditionally, on-site screening is performed by means of colour tests which are difficult to interpret and lack selectivity. By presenting the distinct voltammetric response of cocaine, cutting agents, binary mixtures of cocaine and street samples in solution and powder street samples, we were able to elucidate the electrochemical fingerprint of all these compounds. The new electrochemical concept holds considerable promise as an on-site screening method.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000371021900094 Publication Date 2016-01-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-6520 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.668 Times cited 37 Open Access  
  Notes ; The authors acknowledge BELSPO for funding the APTADRU project (BR/314/PI/ APTADRU). ; Approved Most recent IF: 8.668  
  Call Number UA @ admin @ c:irua:130404 Serial 5591  
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Author Pilehvar, S.; Dardenne, F.; Blust, R.; De Wael, K. url  openurl
  Title Electrochemical sensing of phenicol antibiotics at gold Type A1 Journal article
  Year 2012 Publication International journal of electrochemical science Abbreviated Journal Int J Electrochem Sc  
  Volume 7 Issue 6 Pages 5000-5011  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Phenicols are an effective and a broad spectrum class of antibiotics which has lost favour due to their side effects on human health. A rapid and sensitive electrochemical detection system is developed for the simultaneous detection of chloramphenicol (CAP), thiamphenicol (TAP) and florfenicol (FF). The electrochemical behaviour of CAP in the presence of its derivatives was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). At a gold electrode, CAP gives rise to a sensitive cathodic peak at −0.68V (versus SCE) in a tris buffer solution (pH 7.6). This behavior gives us the opportunity to introduce a method for sensing CAP electrochemically in the presence of its derivatives. Calibration graphs were linear in the 2.5-7.4 μmol L-1 concentration range. Deviations from linearity were observed for higher concentrations and this was interpreted to be due to kinetic limitation caused by the saturation of CAP and its reduction products onto the gold electrode surface. A limit of detection of 1 μmol L-1 was found.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1452-3981 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.469 Times cited Open Access  
  Notes ; ; Approved Most recent IF: 1.469; 2012 IF: NA  
  Call Number UA @ admin @ c:irua:98344 Serial 5595  
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Author Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K. url  doi
openurl 
  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 (up) 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 Florea, A.; De Jong, M.; De Wael, K. pdf  url
doi  openurl
  Title Electrochemical strategies for the detection of forensic drugs Type A1 Journal article
  Year 2018 Publication Current opinion in electrochemistry Abbreviated Journal  
  Volume 11 Issue 11 Pages 34-40  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Illicit drugs consumption and trafficking is spread worldwide and remains an increasing challenge for local authorities. Forensic drugs and their metabolites are released into wastewaters due to human excretion after illegal consumption of drugs and occasionally due to disposal of clandestine laboratory wastes into sewage systems, being recently classified as the latest group of emerging pollutants. Hence, it is essential to have efficient and accurate methods to detect these type of compounds in seized street samples, biological fluids and wastewaters in order to reduce and prevent trafficking and consumption and negative effects on aquatic systems. Electrochemical strategies offer a fast, portable, low-cost and accurate alternative to chromatographic and spectrometric methods, for the analysis of forensic drugs and metabolites in different matrices. Recent electrochemical strategies applied to the detection of illicit drugs in wastewaters, biological fluids and street samples are presented in this review, together with the impact of drug consumption on the environment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000453710900007 Publication Date 2018-07-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2451-9103; 2451-9111 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 7 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 financial support from BELSPO, IOF-SBO and UAntwerp. ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:152366 Serial 5597  
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Author De Wael, K.; Verstraete, A.; van Vlierberghe, S.; Dejonghe, W.; Dubruel, P.; Adriaens, A. url  openurl
  Title The electrochemistry of a gelatin modified gold electrode Type A1 Journal article
  Year 2011 Publication International journal of electrochemical science Abbreviated Journal Int J Electrochem Sc  
  Volume 6 Issue 6 Pages 1810-1819  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract This paper discusses the electrochemical behaviour of gelatin coated gold electrodes in physiological pH conditions in a potential window −1.5 till 1.0 V vs SCE by performing cyclic voltammetry. A comparison is made between gelatin A and gelatin B, which have respectively a positive and a negative net charge at physiological pH. The deposition of gelatin onto the gold surface is confirmed by means of attenuated total reflection-infrared (ATR-IR) spectroscopic analyses.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1452-3981 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles  
  Impact Factor 1.469 Times cited Open Access  
  Notes ; The authors would like to acknowledge the Flemish Institute for Technological Research (VITO, Belgium) and the Research Foundation-Flanders (FWO, Belgium) for the Ph.D. funding granted to Annelies Verstraete. Karolien De Wael and Sandra Van Vlierberghe are also grateful to the Research Foundation-Flanders (FWO, Belgium) for their postdoctoral fellowship. ; Approved Most recent IF: 1.469; 2011 IF: 3.729  
  Call Number UA @ admin @ c:irua:89617 Serial 5598  
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Author Bottari, F.; De Wael, K. pdf  url
doi  openurl
  Title Electrodeposition of gold nanoparticles on boron doped diamond electrodes for the enhanced reduction of small organic molecules Type A1 Journal article
  Year 2017 Publication Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. Abbreviated Journal J Electroanal Chem  
  Volume 801 Issue Pages 521-526  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The performance of gold nanoparticles electrodeposited on boron doped diamond (BDD) electrodes was investigated in respect to the reduction of chloramphenicol (CAP), an antibiotic of the phenicols family. The chosen deposition protocol, three nucleation-growing pulses, shows a remarkable surface coverage, with an even distribution of average-sized gold particles (~ 50 nm), and it was proven capable of generating a three-fold increase in the CAP reduction current. A calibration plot for CAP detection was obtained in the micromolar range (535 μM) with good correlation coefficient (0.9959) and an improved sensitivity of 0.053 μA μM− 1 mm− 2 compared to the electrochemistry of CAP at a bare BDD electrode.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000411847500065 Publication Date 2017-08-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1572-6657 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.012 Times cited 4 Open Access  
  Notes ; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation Flanders (FWO) (project G037415N). ; Approved Most recent IF: 3.012  
  Call Number UA @ admin @ c:irua:146372 Serial 5600  
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Author Horemans, B.; Cardell, C.; Bencs, L.; Kontozova-Deutsch, V.; De Wael, K.; Van Grieken, R. pdf  doi
openurl 
  Title Evaluation of airborne particles at the Alhambra monument in Granada, Spain Type A1 Journal article
  Year 2011 Publication Microchemical journal Abbreviated Journal Microchem J  
  Volume 99 Issue 2 Pages 429-438  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract As a part of an ongoing investigation regarding the air quality at the Alhambra monument (UNESCO World Cultural Heritage), indoor and outdoor atmospheric aerosols (PM1 and PM10-1) and pollutant gases (O3, NO2, SO2 and NH3) were studied during summer and winter. Bulk elements, ionic compounds and black carbon (BC) in aerosols were analyzed with X-ray fluorescence spectrometry, ion chromatography and aethalometry/reflectometry, respectively. Natural PM10-1 aerosols, such as carbonate-rich soil and sea salts, reacted with a typical urban atmosphere, producing a mixture of particulates with diverse chemical composition. The content/formation of secondary inorganic aerosols depended on the air temperature and absolute humidity. Ratios of typical mineral elements (i.e., Ti/Fe and Si/Fe) showed that Saharan dust events contribute to the composition of the observed mineral aerosol content. BC, V and Ni originated from diesel exhaust, while Cu, Cr, Pb and Zn came mainly from non-exhaust vehicular emissions. Weathering phenomena, such as blackening and pigment discoloration, which could arise from gradual aerosol deposition indoors, are discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000295770700042 Publication Date 2011-06-28  
  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 39 Open Access  
  Notes ; ; Approved Most recent IF: 3.034; 2011 IF: 3.048  
  Call Number UA @ admin @ c:irua:91720 Serial 5611  
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Author Monico, L.; Janssens, K.; Hendriks, E.; Vanmeert, F.; van der Snickt, G.; Cotte, M.; Falkenberg, G.; Brunetti, B.G.; Miliani, C. pdf  doi
openurl 
  Title Evidence for degradation of the chrome yellows in Van Gogh's sunflowers : a study using noninvasive in situ methods and synchrotron-radiation-based x-ray techniques Type A1 Journal article
  Year 2015 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 54 Issue 47 Pages 13923-13927  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x approximate to 0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., Cr-III compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000367722500009 Publication Date 2015-10-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 24 Open Access  
  Notes ; We acknowledge financial support from the Italian MIUR project SICH-PRIN (2010329WPF_001) and BELSPO (Brussels) Project S2-ART (SD04A), GOA “SOLARPAINT” (Research Fund Antwerp University, BOF-2015), and FWO (Brussels) projects G.0C12.13, G.0704.08, G.01769.09. We thank ESRF (EC-1051, HG-26) and DESY (I-20120312 EC) for beamtime grants received. Noninvasive analysis of Sunflowers were supported by the EU FP7 programme CHARISMA (Grant 228330) and the Fund Inbev-Baillet Latour (Brussels). L.M. acknowledges financial support from the CNR Short Term Mobility Programme-2013. We thank Muriel Geldof, Luc Megens, Suzan de Groot (The Netherlands Cultural Heritage Agency, RCE), Chiara Grazia, David Buti (CNR-ISTM and SMAArt Centre), and the staff of the Van Gogh Museum for their collaboration. ; Approved Most recent IF: 11.994; 2015 IF: 11.261  
  Call Number UA @ admin @ c:irua:131110 Serial 5617  
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Author Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K. url  doi
openurl 
  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 (up) 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  
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Author Anaf, W.; Janssens, K.; De Wael, K. pdf  doi
openurl 
  Title Formation of metallic mercury during photodegradation/photodarkening of \alpha-HgS : electrochemical evidence Type A1 Journal article
  Year 2013 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 52 Issue 48 Pages 12568-12571  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Das rote Pigment α-HgS neigt in Gegenwart von Licht und Chloridionen zur Schwärzung. Als Grund für die Zersetzung und Entfärbung werden die Bildung von (schwarzem) β-HgS oder Quecksilbermetall vermutet, doch diese Substanzen wurden noch nicht auf natürlich oder künstlich zersetzter HgS-Farbe nachgewiesen. Elektrochemische Experimente belegen nun die Bildung von Quecksilbermetall in Gegenwart von Licht und Chloridionen.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000327582900015 Publication Date 2013-10-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 19 Open Access  
  Notes ; The authors acknowledge L. Klaassen for valuable discussions and providing samples. We acknowledge financial support from the SDD programme (S2-ART project) of the Belgian Federal Goverment. ; Approved Most recent IF: 11.994; 2013 IF: 11.336  
  Call Number UA @ admin @ c:irua:111265 Serial 5626  
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Author Rather, J.A.; De Wael, K. pdf  doi
openurl 
  Title Fullerene-C60 sensor for ultra-high sensitive detection of bisphenol-A and its treatment by green technology Type A1 Journal article
  Year 2013 Publication Sensors and actuators : B : chemical Abbreviated Journal Sensor Actuat B-Chem  
  Volume 176 Issue Pages 110-117  
  Keywords (up) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Endocrine disruptors (EDCs) are environmental pollutants that, once incorporated into an organism, affect the hormonal balance of humans and various species. Its presence in environment is of great importance in water quality related questions. The proposed method describes the development of an accurate, sensitive and selective sensor for the detection of bisphenol-A (BPA) and its treatment by green technology. A fullerene (C60) fabricated electrochemical sensor was developed for the ultrasensitive detection of BPA. The homemade sensor was characterized by scanning electron microscopy, electrochemical impedance spectroscopy and chronocoulometry. The influence of measuring parameters such as pH and C60 loading on the analytical performance of the sensor was evaluated. Various kinetic parameters such as electron transfer number (n); charge transfer coefficient (α); electrode surface area (A) and diffusion coefficient (D) were also calculated. Under the optimal conditions, the oxidation peak current was linear over the concentration range of 74 nM to 0.23 μM with the detection limit (LOD) of 3.7 nM. The fabricated sensor was successfully applied to the determination of BPA in wastewater samples and it has promising analytical applications for the direct determination of BPA at trace level.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000319867500017 Publication Date 2012-09-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-4005 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.401 Times cited 79 Open Access  
  Notes ; The authors are highly thankful for the mobility grant (Non-Europe Postdoc Fellowship) for one of the author (Jahangir Ahmad Rather) supported by the Belgian Federal Science Policy (Belspo) co-funded by the Marie Curie Actions from the European Commission. ; Approved Most recent IF: 5.401; 2013 IF: 3.840  
  Call Number UA @ admin @ c:irua:101055 Serial 5630  
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