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Ortiz-Aguayo, D.; De Wael, K.; del Valle, M. |
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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 |
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Year |
2021 |
Publication |
Journal Of Electroanalytical Chemistry |
Abbreviated Journal  |
J Electroanal Chem |
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Volume |
902 |
Issue |
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Pages |
115770 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
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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. |
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000714415500006 |
Publication Date |
2021-10-13 |
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Edition |
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ISSN |
1572-6657; 1873-2569 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.012 |
Times cited |
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Open Access |
OpenAccess |
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Approved |
Most recent IF: 3.012 |
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Call Number |
UA @ admin @ c:irua:184018 |
Serial |
8745 |
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Author |
Trashin, S.; De Jong, M.; Luyckx, E.; Dewilde, S.; De Wael, K. |
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Title |
Electrochemical evidence for neuroglobin activity on NO at physiological concentrations |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of biological chemistry |
Abbreviated Journal |
J Biol Chem |
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Volume |
291 |
Issue |
36 |
Pages |
18959-18966 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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. |
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Wos |
000383242300031 |
Publication Date |
2016-07-12 |
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Edition |
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ISSN |
0021-9258; 1083-351x |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.125 |
Times cited |
11 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:134340 |
Serial |
5590 |
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Author |
Eliaerts, J.; Meert, N.; Dardenne, P.; Baeten, V.; Pierna, J.-A.F.; Van Durme, F.; De Wael, K.; Samyn, N. |
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Title |
Comparison of spectroscopic techniques combined with chemometrics for cocaine powder analysis |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Analytical Toxicology |
Abbreviated Journal |
J Anal Toxicol |
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Volume |
44 |
Issue |
8 |
Pages |
851-860 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Spectroscopic techniques combined with chemometrics are a promising tool for analysis of seized drug powders. In this study, the performance of three spectroscopic techniques [Mid-InfraRed (MIR), Raman and Near-InfraRed (NIR)] was compared. In total, 364 seized powders were analyzed and consisted of 276 cocaine powders (with concentrations ranging from 4 to 99 w%) and 88 powders without cocaine. A classification model (using Support Vector Machines [SVM] discriminant analysis) and a quantification model (using SVM regression) were constructed with each spectral dataset in order to discriminate cocaine powders from other powders and quantify cocaine in powders classified as cocaine positive. The performances of the models were compared with gas chromatography coupled with mass spectrometry (GC-MS) and gas chromatography with flame-ionization detection (GC-FID). Different evaluation criteria were used: number of false negatives (FNs), number of false positives (FPs), accuracy, root mean square error of cross-validation (RMSECV) and determination coefficients (R-2). Ten colored powders were excluded from the classification data set due to fluorescence background observed in Raman spectra. For the classification, the best accuracy (99.7%) was obtained with MIR spectra. With Raman and NIR spectra, the accuracy was 99.5% and 98.9%, respectively. For the quantification, the best results were obtained with NIR spectra. The cocaine content was determined with a RMSECV of 3.79% and a R-2 of 0.97. The performance of MIR and Raman to predict cocaine concentrations was lower than NIR, with RMSECV of 6.76% and 6.79%, respectively and both with a R-2 of 0.90. The three spectroscopic techniques can be applied for both classification and quantification of cocaine, but some differences in performance were detected. The best classification was obtained with MIR spectra. For quantification, however, the RMSECV of MIR and Raman was twice as high in comparison with NIR. Spectroscopic techniques combined with chemometrics can reduce the workload for confirmation analysis (e.g., chromatography based) and therefore save time and resources. |
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Wos |
000606735000011 |
Publication Date |
2020-08-04 |
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ISSN |
0146-4760; 1945-2403 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.5; 2020 IF: 2.409 |
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Call Number |
UA @ admin @ c:irua:175117 |
Serial |
7697 |
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Author |
Vermeulen, M.; Sanyova, J.; Janssens, K.; Nuyts, G.; De Meyer, S.; De Wael, K. |
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Title |
The darkening of copper- or lead-based pigments explained by a structural modification of natural orpiment : a spectroscopic and electrochemical study |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
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Volume |
32 |
Issue |
7 |
Pages |
1331-1341 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A combined Raman and electrochemical study of natural orpiment (As2S3), an arsenic sulfide pigment, was used to assess the quick formation of oxidized species such as arsenic oxide (As2O3) upon exposing the pigment to 405 nm or 532 nm monochromatic light while simultaneously recording the Raman spectra of the exposed sample. During this process, a distortion of the main band at 355 cm−1, associated with the stretching of the AsS3/2 pyramids of natural orpiment, was observed as well as an increased intensity of the 359 cm−1 band, corresponding to covalent AsAs bonds in natural orpiment. The distortion was accompanied by an overall decrease of the global Raman signal for natural orpiment, which could be explained by a loss in the crystal structure. The same phenomena were recorded in reference natural orpiment model paint samples stored for a long time together with verdigris (Cu(OH)2·(CH3COO)2·5H2O) and minium (Pb3O4) paints, the latter two appearing darkened on their sides closest to the orpiment sample as well as in several historical samples containing natural orpiment mixed with various blue pigments. By SEM-EDX and XRPD analysis, respectively on loose material and cast thin-sections of model paint samples, the darkening was identified as dark sulfide species such as chalcocite (Cu2S) and galena (PbS), suggesting the release of volatile sulfide or related species by the natural orpiment paint. XANES analyses of paint samples presenting AsAs bond increase indicated the presence of sulfur species most likely identified as organosulfur compounds formed upon the AsAs bond formation and explained the darkening of the Cu- and Pb-based pigments. To the best of our knowledge, this article reports for the first time the light-induced formation of AsAs bonds in natural orpiment used as an artists' pigment and objectively demonstrates the incompatibility between orpiment and (arsenic) sulfide-sensitive pigments. |
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Wos |
000404998500007 |
Publication Date |
2017-05-31 |
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Edition |
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ISSN |
0267-9477 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.379 |
Times cited |
10 |
Open Access |
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Notes |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). We gratefully acknowledge Julie Arslanoglu (Conservation and Scientific Research Department at the Metropolitan Museum of Art, New York, USA) for providing us the orpiment, verdigris and minium mock-up samples. We gratefully acknowledge the Paul Scherrer Institut, Villigen, Switzerland and the German Electron Synchrotron (DESY) for provision of synchrotron radiation beamtimes at respectively beamlines of the SLS and Petra III. ; |
Approved |
Most recent IF: 3.379 |
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Call Number |
UA @ admin @ c:irua:144384 |
Serial |
5564 |
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Author |
Bottari, F.; Daems, E.; de Vries, A.-M.; Van Wielendaele, P.; Trashin, S.; Blust, R.; Sobott, F.; Madder, A.; Martins, J.C.; De Wael, K. |
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Title |
Do aptamers always bind? The need for a multifaceted analytical approach when demonstrating binding affinity between aptamer and low molecular weight compounds |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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Volume |
142 |
Issue |
46 |
Pages |
jacs.0c08691-19630 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Medical Biochemistry |
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Abstract |
In this manuscript, we compare different analytical methodologies to validate or disprove the binding capabilities of aptamer sequences. This was prompted by the lack of a universally accepted and robust quality control protocol for the characterization of aptamer performances coupled with the observation of independent yet inconsistent data sets in the literature. As an example, we chose three aptamers with a reported affinity in the nanomolar range for ampicillin, a β-lactam antibiotic, used as biorecognition elements in several detection strategies described in the literature. Application of a well-known colorimetric assay based on aggregation of gold nanoparticles (AuNPs) yielded conflicting results with respect to the original report. Therefore, ampicillin binding was evaluated in solution using isothermal titration calorimetry (ITC), native nano-electrospray ionization mass spectrometry (native nESI-MS), and 1H-nuclear magnetic resonance spectroscopy (1H NMR). By coupling the thermodynamic data obtained with ITC with the structural information on the binding event given by native nESI-MS and 1H NMR we could verify that none of the ampicillin aptamers show any specific binding with their intended target. The effect of AuNPs on the binding event was studied by both ITC and 1H NMR, again without providing positive evidence of ampicillin binding. To validate the performance of our analytical approach, we investigated two well-characterized aptamers for cocaine/quinine (MN4), chosen for its nanomolar range affinity, and l-argininamide (1OLD) to show the versatility of our approach. The results clearly indicate the need for a multifaceted analytical approach, to unequivocally establish the actual detection potential and performance of aptamers aimed at small organic molecules. |
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Wos |
000592911000024 |
Publication Date |
2020-11-09 |
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Edition |
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ISSN |
0002-7863 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 15; 2020 IF: 13.858 |
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Call Number |
UA @ admin @ c:irua:173136 |
Serial |
6488 |
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Author |
Hellar-Kihampa, H.; Potgieter-Vermaak, S.; De Wael, K.; Lugwisha, E.; van Espen, P.; Van Grieken, R. |
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Title |
Concentration profiles of metal contaminants in fluvial sediments of a rural-urban drainage basin in Tanzania |
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A1 Journal article |
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Year |
2014 |
Publication |
International journal of environmental analytical chemistry |
Abbreviated Journal |
Int J Environ An Ch |
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Volume |
94 |
Issue |
1 |
Pages |
77-98 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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. |
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Wos |
000329774500007 |
Publication Date |
2013-05-24 |
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Abbreviated Series Title |
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Edition |
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ISSN |
0306-7319 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.208 |
Times cited |
5 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:109234 |
Serial |
5547 |
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Author |
Pilehvar, S.; Dardenne, F.; Blust, R.; De Wael, K. |
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Title |
Electrochemical sensing of phenicol antibiotics at gold |
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A1 Journal article |
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Year |
2012 |
Publication |
International journal of electrochemical science |
Abbreviated Journal |
Int J Electrochem Sc |
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Volume |
7 |
Issue |
6 |
Pages |
5000-5011 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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. |
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ISSN |
1452-3981 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.469 |
Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 1.469; 2012 IF: NA |
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Call Number |
UA @ admin @ c:irua:98344 |
Serial |
5595 |
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Author |
De Wael, K.; Verstraete, A.; van Vlierberghe, S.; Dejonghe, W.; Dubruel, P.; Adriaens, A. |
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Title |
The electrochemistry of a gelatin modified gold electrode |
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A1 Journal article |
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Year |
2011 |
Publication |
International journal of electrochemical science |
Abbreviated Journal |
Int J Electrochem Sc |
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Volume |
6 |
Issue |
6 |
Pages |
1810-1819 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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. |
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ISSN |
1452-3981 |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
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Impact Factor |
1.469 |
Times cited |
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Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:89617 |
Serial |
5598 |
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Author |
Dragan, A.-M.; Truta, F.M.; Tertis, M.; Florea, A.; Schram, J.; Cernat, A.; Feier, B.; De Wael, K.; Cristea, C.; Oprean, R. |
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Title |
Electrochemical fingerprints of illicit drugs on graphene and multi-walled carbon nanotubes |
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A1 Journal article |
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Year |
2021 |
Publication |
Frontiers In Chemistry |
Abbreviated Journal |
Front Chem |
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Volume |
9 |
Issue |
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Pages |
641147 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Illicit drugs use and abuse remains an increasing challenge for worldwide authorities and, therefore, it is important to have accurate methods to detect them in seized samples, biological fluids and wastewaters. They are recently classified as the latest group of emerging pollutants as their consumption increased tremendously in recent years. Nanomaterials have gained much attention over the last decade in the development of sensors for a myriad of applications. The applicability of these nanomaterials, functionalized or not, significantly increases and it is therefore highly suitable for use in the detection of illicit drugs. We have assessed the suitability of various nanoplatforms, such as graphene (GPH), multi-walled carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) for the electrochemical detection of illicit drugs. GPH and MWCNTs were chosen as the most suitable platforms and cocaine, 3,4-methylendioxymethamfetamine (MDMA), 3-methylmethcathinone (MMC) and alpha-pyrrolidinovalerophenone (PVP) were tested. Due to the hydrophobicity of the nanomaterials-based platforms which led to low signals, two strategies were followed namely, pretreatment of the electrodes in sulfuric acid by cyclic voltammetry and addition of Tween 20 to the detection buffer. Both strategies led to an increase in the oxidation signal of illicit drugs. Binary mixtures of illicit drugs with common adulterants found in street samples were also investigated. The proposed strategies allowed the sensitive detection of illicit drugs in the presence of most adulterants. The suitability of the proposed sensors for the detection of illicit drugs in spiked wastewaters was finally assessed. |
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000634708900001 |
Publication Date |
2021-03-16 |
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ISSN |
2296-2646 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.994 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
|
Approved |
Most recent IF: 3.994 |
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| |
Call Number |
UA @ admin @ c:irua:177704 |
Serial |
7861 |
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| Permanent link to this record |
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| |
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Author |
Truta, F.; Florea, A.; Cernat, A.; Tertis, M.; Hosu, O.; De Wael, K.; Cristea, C. |
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| |
Title |
Tackling the problem of sensing commonly abused drugs through nanomaterials and (bio)recognition approaches |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Frontiers In Chemistry |
Abbreviated Journal |
Front Chem |
|
| |
Volume |
8 |
Issue |
|
Pages |
561638 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
We summarize herein the literature in the last decade, involving the use of nanomaterials and various (bio)recognition elements, such as antibodies, aptamers and molecularly imprinted polymers, for the development of sensitive and selective (bio)sensors for illicit drugs with a focus on electrochemical transduction systems. The use and abuse of illicit drugs remains an increasing challenge for worldwide authorities and, therefore, it is important to have accurate methods to detect them in seized samples, biological fluids and wastewaters. They are recently classified as the latest group of “emerging pollutants,” as their consumption has increased tremendously in recent years. Nanomaterials, antibodies, aptamers and molecularly imprinted polymers have gained much attention over the last decade in the development of (bio)sensors for a myriad of applications. The applicability of these (nano)materials, functionalized or not, has significantly increased, and are therefore highly suitable for use in the detection of drugs. Lately, such functionalized nanoscale materials have assisted in the detection of illicit drugs fingerprints, providing large surface area, functional groups and unique properties that facilitate sensitive and selective sensing. The review discusses the types of commonly abused drugs and their toxicological implications, classification of functionalized nanomaterials (graphene, carbon nanotubes), their fabrication, and their application on real samples in different fields of forensic science. Biosensors for drugs of abuse from the last decade's literature are then exemplified. It also offers insights into the prospects and challenges of bringing the functionalized nanobased technology to the end user in the laboratories or in-field. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000589960100001 |
Publication Date |
2020-11-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2296-2646 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.5 |
Times cited |
|
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 5.5; 2020 IF: 3.994 |
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| |
Call Number |
UA @ admin @ c:irua:174278 |
Serial |
8639 |
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| Permanent link to this record |
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| |
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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. |
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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 |
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| |
Volume |
46 |
Issue |
21 |
Pages |
12162-12169 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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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). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000310665000082 |
Publication Date |
2012-10-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
0013-936X;1520-5851; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.198 |
Times cited |
5 |
Open Access |
|
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| |
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 |
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| |
Call Number |
UA @ lucian @ c:irua:101411 |
Serial |
2557 |
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| Permanent link to this record |
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Author |
Kardel, F.; Wuyts, K.; De Wael, K.; Samson, R. |
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Title |
Biomonitoring of atmospheric particulate pollution via chemical composition and magnetic properties of roadside tree leaves |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Environmental Science and Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
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| |
Volume |
25 |
Issue |
26 |
Pages |
25994-26004 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Particulate matter (PM) is a main atmospheric pollution which threats human health and well-being. In this research, we chemically and magnetically analysed roadside tree leaves, collected from three tree species in two main roads (from two different cities) and a reference area, for 28 elements and the saturation isothermal remanent magnetisation. Comparison of unwashed and washed leaves revealed that deposited particles on the leaf surface contain various elements including Al, Ca, Fe, Mg, Mn, Na, Si, Ti, Ba, Co, Cr, Cu, Ni, Rb, V, Zn and Zr. Moreover, there was no significant difference between washed/unwashed leaves in Cl, K, P, S, As, Cd, Cs, Pb, Sn and Sr concentrations, which indicates tree leaves may not be a suitable biomonitor for these elements. Our results showed that site and tree species are important factors which affect atmospheric elements deposition. Among the three considered tree species, Chamaecyparis lawsoniana showed the highest potential for atmospheric particle accumulation. The PCA results revealed that Al, Fe, Ti, Co, Cr, Cu, Ni, Rb, Si, V, Zn and Zr indicated emissions from road traffic activities and soil dust; Ca, Mg and Na from sea salts and Mn and Sb from industrial activity. The biplot results showed that the site effect was much stronger than the species effect for all elements and saturation isothermal remanent magnetisation (SIRM) values. Moreover, elements from traffic, industrial activity and soil dust are significantly correlated with leaf SIRM indicating that leaf SIRM can be a suitable bioindicator of exposure to traffic-derived particles and soil dust, and not from sea salts. It is concluded that chemical composition and SIRM of urban tree leaves can serve as a good indicator of atmospheric PM pollution in Iran and anywhere else where the studied trees grow. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000443329100034 |
Publication Date |
2018-07-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.741 |
Times cited |
6 |
Open Access |
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| |
Notes |
; ; |
Approved |
Most recent IF: 2.741 |
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| |
Call Number |
UA @ admin @ c:irua:153669 |
Serial |
5489 |
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| Permanent link to this record |
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Author |
Anaf, W.; Horemans, B.; Madeira, T.I.; Carvalho, M.L.; De Wael, K.; Van Grieken, R. |
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| |
Title |
Effects of a constructional intervention on airborne and deposited particulate matter in the Portuguese National Tile Museum, Lisbon |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Environmental Science and Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
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| |
Volume |
20 |
Issue |
3 |
Pages |
1849-1857 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
In the 1970s, a large ambulatory of the National Tile Museum, Lisbon, was closed with glass panes on both ground and first floor. Although this design was meant to protect the museum collection from ambient air pollutants, small openings between the glass panes remain, creating a semi-enclosed corridor. The effects of the glass panes on the indoor air quality were evaluated in a comparative study by monitoring the airborne particle concentration and the extent of particle deposition at the enclosed corridor as well as inside the museum building. Comparison of the indoor/outdoor ratio of airborne particle concentration demonstrated a high natural ventilation rate in the enclosed corridor as well as inside the museum building. PM10 deposition velocities on vertical surfaces were estimated in the order of 3 × 10−4 m s−1 for both indoor locations. Also, the deposition rates of dark-coloured and black particles in specific were very similar at both indoor locations, causing visual degradation. The effectiveness of the glass panes in protecting the museum collection is discussed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000315442500061 |
Publication Date |
2012-07-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.741 |
Times cited |
15 |
Open Access |
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| |
Notes |
; ; |
Approved |
Most recent IF: 2.741; 2013 IF: 2.757 |
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| |
Call Number |
UA @ admin @ c:irua:100214 |
Serial |
5583 |
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| Permanent link to this record |
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Author |
Castanheiro, A.; Wuyts, K.; Hofman, J.; Nuyts, G.; De Wael, K.; Samson, R. |
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Title |
Morphological and elemental characterization of leaf-deposited particulate matter from different source types : a microscopic investigation |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Environmental Science And Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
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| |
Volume |
28 |
Issue |
20 |
Pages |
25716-25732 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Particulate matter (PM) deposition on urban green enables the collection of particulate pollution from a diversity of contexts, and insight into the physico-chemical profiles of PM is key for identifying main polluting sources. This study reports on the morphological and elemental characterization of PM2-10 deposited on ivy leaves from five different environments (forest, rural, roadside, train, industry) in the region of Antwerp, Belgium. Ca. 40,000 leaf-deposited particles were thoroughly investigated by particle-based analysis using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX) and their physico-chemical characteristics were explored for PM source apportionment purposes. The size distribution of all deposited particles was biased towards small-sized PM, with 32% of the particles smaller than 2.5 mu m (PM2.5) and median diameters of 2.80-3.09 mu m. The source type influenced both the particles' size and morphology (aspect ratio and shape), with roadside particles being overall the smallest in size and the most spherical. While forest and rural elemental profiles were associated with natural PM, the industry particles revealed the highest anthropogenic metal input. PM2-10 profiles for roadside and train sites were rather comparable and only distinguishable when evaluating the fine (2-2.5 mu m) and coarse (2.5-10 mu m) PM fractions separately, which enabled the identification of a larger contribution of combustion-derived particles (small, circular, Fe-enriched) at the roadside compared to the train. Random forest prediction model classified the source type correctly for 61-85% of the leaf-deposited PM. The still modest classification accuracy denotes the influence of regional background PM and demands for additional fingerprinting techniques to facilitate source apportionment. Nonetheless, the obtained results demonstrate the utility of leaf particle-based analysis to fingerprint and pinpoint source-specific PM, particularly when considering both the composition and size of leaf-deposited particles. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000609067300006 |
Publication Date |
2021-01-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.741 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
|
Approved |
Most recent IF: 2.741 |
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| |
Call Number |
UA @ admin @ c:irua:176082 |
Serial |
8282 |
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| Permanent link to this record |
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Author |
Lybaert, J.; Maes, B.U.W.; Tehrani, K.A.; De Wael, K. |
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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 |
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| |
Volume |
182 |
Issue |
|
Pages |
693-698 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY) |
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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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000365075800084 |
Publication Date |
2015-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.798 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.798; 2015 IF: 4.504 |
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| |
Call Number |
UA @ admin @ c:irua:127676 |
Serial |
5599 |
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| Permanent link to this record |
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Author |
Pauwels, D.; Ching, H.Y.V.; Samanipour, M.; Neukermans, S.; Hereijgers, J.; Van Doorslaer, S.; De Wael, K.; Breugelmans, T. |
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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 |
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| |
Volume |
271 |
Issue |
271 |
Pages |
10-18 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT) |
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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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000430369800002 |
Publication Date |
2018-03-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.798 |
Times cited |
2 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:150463 |
Serial |
5652 |
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| Permanent link to this record |
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Author |
Lybaert, J.; Tehrani, K.A.; De Wael, K. |
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Title |
Mediated electrolysis of vicinal diols by neocuproine palladium catalysts |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
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Volume |
247 |
Issue |
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Pages |
685-691 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY) |
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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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000408582300072 |
Publication Date |
2017-07-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.798 |
Times cited |
|
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.798 |
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Call Number |
UA @ admin @ c:irua:144118 |
Serial |
5706 |
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| Permanent link to this record |
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Author |
Gaetani, C.; Gheno, G.; Borroni, M.; De Wael, K.; Moretto, L.M.; Ugo, P. |
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Title |
Nanoelectrode ensemble immunosensing for the electrochemical identification of ovalbumin in works of art |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
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| |
Volume |
312 |
Issue |
312 |
Pages |
72-79 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
This research is aimed to the study and application of an electrochemical immunosensor for the detection of ovalbumin (OVA) from egg white (or albumen) used as a binder in some works of art, such as some historical photographic prints and tempera paintings. The immunosensor takes advantage of the interesting biodetection capabilities offered by nanoelectrode ensembles (NEEs). The NEEs used to this aim are prepared by template deposition of gold nanoelectrodes within the pores of track-etched polycarbonate (PC) membranes. The affinity of polycarbonate for proteins is exploited to capture OVA from the aqueous extract obtained by incubation in phosphate buffer of a small sample fragment (<1 mg). The captured protein is reacted selectively with anti-OVA antibody, labelled with glucose oxidase (GOx). In the case of positive response, the addition of the GOx substrate (i.e. glucose) and a suitable redox mediator (a ferrocenyl derivative) reflects in the up rise of an electrocatalytic oxidation current, which depends on the OVA amount captured on the NEE, this amount correlating with OVA concentration in the extract. After optimization, the sensor is successfully applied to identify OVA in photographic prints dating back to the late 19th century, as well as in ancient tempera paintings from the 15th and 18th centuries. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000468595500008 |
Publication Date |
2019-04-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.798 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.798 |
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| |
Call Number |
UA @ admin @ c:irua:159573 |
Serial |
5743 |
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| Permanent link to this record |
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Author |
Stefan, G.; Hosu, O.; De Wael, K.; Jesus Lobo-Castanon, M.; Cristea, C. |
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Title |
Aptamers in biomedicine : selection strategies and recent advances |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Electrochimica Acta |
Abbreviated Journal |
Electrochim Acta |
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| |
Volume |
376 |
Issue |
|
Pages |
137994 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Aptamers have come in the spotlight as bio-mimetic molecular recognition elements in the field of biomedicine due to various applications in diagnostics, drug delivery, therapeutics, and pharmaceutical analysis. Aptamers are composed of nucleic acid strands (DNA or RNA) that can specifically interact in a three-dimensional tailored design with the target molecule. The basic method to generate aptamers is Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Recent technological advances in aptamer selection allow for faster and cheaper production of a new generation of high-affinity aptamers compared to the traditional SELEX, which can last up to several months. Rigorous characterization performed by multiple research groups endorsed several well-defined aptamer sequences. Binding affinity, nature of the biomolecular interactions and structural characterization are of paramount importance for aptamer screening and development of applications. However, remarkable challenges still need to be dealt with before the aptamers can make great contributions to the biomedical field. Poor specificity and sensitivity, questionable clinical use, low drug loading, in vivo stability and toxicity are only some of the identified challenges. This review accounts for the 30th celebration of the SELEX technology underlining the most important aptamers' achievements in the biomedical field within mostly the past five years. Aptamers' advantages over antibodies are discussed. Because of potential clinical translational utility, insights of remarkable developments in aptamer-based methods for diagnosis and monitoring of disease biomarkers and pharmaceuticals are discussed focusing on the recent studies (2015-2020). The current challenges and promising opportunities for aptamers for therapeutic and theragnostic purposes are also presented. (C) 2021 Elsevier Ltd. All rights reserved. |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000634761900003 |
Publication Date |
2021-02-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.798 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
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Approved |
Most recent IF: 4.798 |
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| |
Call Number |
UA @ admin @ c:irua:177677 |
Serial |
7491 |
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| Permanent link to this record |
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Author |
Schram, J.; Thiruvottriyur Shanmugam, S.; Sleegers, N.; Florea, A.; Samyn, N.; van Nuijs, A.L.N.; De Wael, K. |
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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 |
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| |
Volume |
367 |
Issue |
|
Pages |
137515 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
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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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000607620700010 |
Publication Date |
2020-11-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.798 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 4.798 |
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| |
Call Number |
UA @ admin @ c:irua:176083 |
Serial |
8177 |
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| Permanent link to this record |
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Author |
Mendonça, C.D.; Khan, S.U.; Rahemi, V.; Verbruggen, S.W.; Machado, S.A.S.; De Wael, K. |
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Title |
Surface plasmon resonance-induced visible light photocatalytic TiO₂ modified with AuNPs for the quantification of hydroquinone |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Electrochimica Acta |
Abbreviated Journal |
Electrochim Acta |
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| |
Volume |
389 |
Issue |
|
Pages |
138734 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The impregnation of size-controlled gold nanoparticles (AuNPs) on an anatase TiO2 structure (AuNPs@TiO2) was studied for the photoelectrochemical detection of hydroquinone (HQ) under visible light illumination integrated into a flow injection analysis (FIA) setup. The crystalline form of TiO2 was preserved during synthesis and the homogeneous distribution of AuNPs over the TiO2 structure was confirmed. Its photoelectrocatalytic activity was improved due to the presence of AuNPs, preventing charge recombination in TiO2 and improving its light absorption ability by the surface plasmon resonance effect (SPR). The FIA system was used in order to significantly reduce the electrode fouling during electroanalysis through periodic washing steps of the electrode surface. During the amperometric detection process, reactive oxygen species (ROS), generated by visible light illumination of AuNPs@TiO2, participate in the oxidation process of HQ. The reduction of the oxidized form of HQ, i.e. benzoquinone (BQ) occurs by applying a negative potential and the measurable amperometric response will be proportional to the initial HQ concentration. The influencing parameters on the response of the amperometric photocurrent such as applied potential, flow rate and pH were investigated. The linear correlation between the amperometric response and the concentration of HQ was recorded (range 0.0125 – 1.0 µM) with a limit of detection (LOD) of 33.8 nM and sensitivity of 0.22 A M−1 cm−2. In this study, we illustrated for the first time that the impregnation of AuNPs in TiO2 allows the sensitive detection of phenolic substances under green laser illumination by using a photoelectrochemical flow system. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000687283100018 |
Publication Date |
2021-06-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.798 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
|
Approved |
Most recent IF: 4.798 |
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| |
Call Number |
UA @ admin @ c:irua:178908 |
Serial |
8626 |
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| Permanent link to this record |
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Author |
Pauwels, D.; Pilehvar, S.; Geboes, B.; Hubin, A.; De Wael, K.; Breugelmans, T. |
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Title |
A new multisine-based impedimetric aptasensing platform |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Electrochemistry communications |
Abbreviated Journal |
Electrochem Commun |
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| |
Volume |
71 |
Issue |
|
Pages |
23-27 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
In this work an aptamer-based biosensor is combined with a multisine electrochemical impedance spectroscopy sensing methodology into a novel and promising biosensing strategy. Employing a multisine instead of a traditional single sine measuring method allows the detection and quantification of parameters that provide information about the accuracy and reliability of the results, such as noise and distortions. This does not only lead to a shorter measurement time, but it also enables an easy and fast evaluation of the quality of the data and fitting, leading to more accurate results. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000383445000006 |
Publication Date |
2016-07-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1388-2481; 1873-1902 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.396 |
Times cited |
1 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.396 |
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Call Number |
UA @ admin @ c:irua:134765 |
Serial |
5746 |
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| Permanent link to this record |
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Author |
Mendonça, C.D.; Rahemi, V.; Hereijgers, J.; Breugelmans, T.; Machado, S.A.S.; De Wael, K. |
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Title |
Integration of a photoelectrochemical cell in a flow system for quantification of 4-aminophenol with titanium dioxide |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Electrochemistry Communications |
Abbreviated Journal |
Electrochem Commun |
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Volume |
117 |
Issue |
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Pages |
106767-5 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT) |
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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. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000552618700004 |
Publication Date |
2020-06-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1388-2481; 1873-1902 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.4 |
Times cited |
1 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:169924 |
Serial |
6547 |
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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. |
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Title |
Electropolymerized o-phenylenediamine on graphite promoting the electrochemical detection of nafcillin |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Electroanalysis |
Abbreviated Journal |
Electroanal |
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Volume |
32 |
Issue |
32 |
Pages |
135-141 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
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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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000482596300001 |
Publication Date |
2019-08-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1040-0397 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.851 |
Times cited |
1 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:162870 |
Serial |
5601 |
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| Permanent link to this record |
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Author |
Rather, J.A.; Debnath, P.; De Wael, K. |
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Title |
Fullerene-\beta-cyclodextrin conjugate based electrochemical sensing device for ultrasensitive detection of p-nitrophenol |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Electroanalysis |
Abbreviated Journal |
Electroanal |
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Volume |
25 |
Issue |
9 |
Pages |
2145-2150 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The article describes the use of a fullerene (C60)-β-cyclodextrin conjugate, synthesized via 1,3-dipolar cycloaddition, for the ultrasensitive electrochemical detection of p-nitrophenol. This conjugate was successfully immobilized on the surface of a glassy carbon electrode and the developed device showed high activity towards p-nitrophenol due to the synergetic effect of C60, the latter becoming highly conductive upon reduction. The determination of p-nitrophenol was performed by using square wave voltammetry over a concentration range from 2.8×10−9 mol L−1 to 4.2×10−7 mol L−1 and the detection limit was calculated to be 1.2×10−9 mol L−1. |
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Address |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000327590600017 |
Publication Date |
2013-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1040-0397 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.851 |
Times cited |
13 |
Open Access |
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Notes |
; Jahangir Ahmad Rather is highly thankful for mobility grant provided by the Belspo co-funded by Marie Curie Actions. ; |
Approved |
Most recent IF: 2.851; 2013 IF: 2.502 |
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Call Number |
UA @ admin @ c:irua:110033 |
Serial |
5629 |
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Author |
Pilehvar, S.; Jambrec, D.; Gebala, M.; Schuhmann, W.; De Wael, K. |
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Title |
Intercalation of proflavine in ssDNA aptamers : effect on binding of the specific target chloramphenicol |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Electroanalysis |
Abbreviated Journal |
Electroanal |
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Volume |
27 |
Issue |
8 |
Pages |
1836-1841 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The structural modification of ssDNA-based aptamers upon specific binding of its target molecule leads to changes of the charge-transfer resistance (Rct) of a negatively-charged free-diffusing redox probe. The aptamer adopts a structure due to self-hybridization which is stabilized using profalvine as intercalator. The pre-organized aptamer structure is used to detect chloramphenicol (CAP) requiring a substantial change of the aptamer structure indicated by a CAP concentration dependent increase in the Rct values. Pre-incubation of the aptamer-modified electrode with an intercalator allows for the modulation of the aptamer/target interaction and hence for a modulation of the CAP-dependent variation of the Rct values. |
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Corporate Author |
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Place of Publication |
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Wos |
000359737500006 |
Publication Date |
2015-06-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1040-0397 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.851 |
Times cited |
5 |
Open Access |
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Notes |
; D. J., M. G., W. S. are grateful for financial support to the Deutsch-Israelische Projektkooperation (DIP) in the framework of the project “Nanoengineered optoelectronics with biomaterials and bioinspired assemblies” funded by the Deutsche Forschungsgemeinschaft. S. P. and K. D. W. are thankful to UA for DOCPRO financial support. ; |
Approved |
Most recent IF: 2.851; 2015 IF: 2.138 |
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Call Number |
UA @ admin @ c:irua:126494 |
Serial |
5666 |
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Author |
Alvarez-Martin, A.; Trashin, S.; Cuykx, M.; Covaci, A.; De Wael, K.; Janssens, K. |
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Title |
Photodegradation mechanisms and kinetics of Eosin-Y in oxic and anoxic conditions |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Dyes and pigments |
Abbreviated Journal |
Dyes Pigments |
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Volume |
145 |
Issue |
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Pages |
376-384 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
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Abstract |
Lakes based on Eosin-Y are extensively used by 19th century artists. Unfortunately, the identification of these pigments in paintings is a difficult task because Eosin-Y degrades very fast under the influence of light. The characterization of the (photo)degradation products of Eosin-Y can be very useful for the identification of these pigments in historic works of art and related cultural heritage artifacts. Furthermore, knowledge on how different factors influence the discoloration process (e.g. different types of irradiation sources and presence/absence of oxygen) is a valuable tool for preventive conservation. To this aim we performed a study on the photodegradation of Eosin-Y in solution under different illumination and in both oxic and anoxic conditions. The photodegradation of Eosin-Y was monitored by UV-VIS spectrophotometry, LC-QTOFMS and electrochemistry techniques. Results indicated higher degradation rates, by a factor of 20 or higher, under illumination with wavelengths near to the main absorbance band of the red pigment. Two different degradation pathways are observed under the conditions studied. LC-QTOFMS and electrochemistry suggested that in the presence of oxygen the degradation mechanism is an oxidative process where the breakdown of the structure causes the total discoloration. Meanwhile under anoxic conditions, a debromination process takes place while the chromophore, and consequently the color of the molecule in solution, remains essentially intact. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000405972900046 |
Publication Date |
2017-06-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0143-7208 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.473 |
Times cited |
18 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.473 |
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Call Number |
UA @ admin @ c:irua:144385 |
Serial |
5770 |
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| Permanent link to this record |
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Author |
Anaf, W.; Schalm, O.; Janssens, K.; De Wael, K. |
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Title |
Understanding the (in)stability of semiconductor pigments by a thermodynamic approach |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Dyes and pigments |
Abbreviated Journal |
Dyes Pigments |
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Volume |
113 |
Issue |
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Pages |
409-415 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
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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. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000346543200052 |
Publication Date |
2014-09-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0143-7208 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.473 |
Times cited |
14 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:118875 |
Serial |
5885 |
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| Permanent link to this record |
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Author |
Beltran, V.; Marchetti, A.; De Meyer, S.; Nuyts, G.; De Wael, K. |
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Title |
Geranium lake pigments : the role of the synthesis on the structure and composition |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Dyes And Pigments |
Abbreviated Journal |
Dyes Pigments |
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Volume |
189 |
Issue |
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Pages |
109260 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Eosin Y has an extraordinary capacity to form complexes with metallic elements, that have applications in many different fields, from photovoltaics and photocatalysis to historical artists? pigments. To unravel the complexes reactivity, it is essential to have a precise knowledge of their structure and composition, as well as how these can be affected by the synthesis protocol, an often underestimated factor. This manuscript presents a thorough investigation of the structure and composition of eosin Y complexes based on Al and Pb, by FTIR, XRPD and Raman spectroscopy, with a particular focus on the effect of the synthesis conditions. Results clearly show the change of the coordination mode in Pb complexes depending on the protocol, while the structure of Al complexes remains stable. In both cases, the formation of by-products was observed. Additionally, a detailed band assignment of the FTIR and Raman spectra of eosin Y and Pb and Al complexes is described, providing interesting details such as the interaction between the metallic ion and the xanthene moiety (chromophore). This is extremely important for the analysis of historical paintings where eosin Y is bonded to metallic ions, as well as for other materials in dye-sensitized solar cells, wastewater treatment or photocatalysis. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000634733200001 |
Publication Date |
2021-03-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0143-7208 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.473 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.473 |
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Call Number |
UA @ admin @ c:irua:177676 |
Serial |
8002 |
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| Permanent link to this record |
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Author |
Eliaerts, J.; Meert, N.; Van Durme, F.; Samyn, N.; De Wael, K.; Dardenne, P. |
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Title |
Practical tool for sampling and fast analysis of large cocaine seizures |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Drug testing and analysis |
Abbreviated Journal |
Drug Test Anal |
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Volume |
10 |
Issue |
6 |
Pages |
1039-1042 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Large quantities of illicit drugs are frequently seized by law enforcement. In such cases, a representative number of samples needs to be quickly examined prior to destruction. No procedure has yet been set up which rapidly provides information regarding the homogeneity of the samples, the presence of controlled substances and the degree of purity. This study establishes a protocol for fast analysis of cocaine and its most common cutting agent, levamisole, in large seizures. The protocol is based on a hypergeometric sampling approach combined with FTIR spectrometry and Support Vector Machines (SVM) algorithms as analysis methods. To demonstrate the practical use of this approach, five large cocaine seizures (consisting between 45 and 85 units) were analysed simultaneously with GC-MS, GC-FID and a portable FTIR spectrometer using Attenuated Total Reflectance (ATR) sampling combined with SVM models. According to the hypergeometric sampling plan of the Drugs Working Group ENFSI guidelines, the required number of subsamples ranged between 19 and 23. Considering the identification analyses, the SVM models detected cocaine and levamisole in all subsamples of cases 1 to 5 (100% correct classification), which was confirmed by GC-MS analysis. Considering the quantification analyses, the SVM models were able to estimate the cocaine and levamisole content in each subsample, compared to GC-FID data. The developed strategy is easy, cost effective and provides immediate information about both the presence and concentration of cocaine and levamisole. By using this new strategy, the number of confirmation analyses with laborious and expensive chromatographic techniques could be significantly reduced. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000435270300016 |
Publication Date |
2018-02-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1942-7603; 1942-7611 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.469 |
Times cited |
1 |
Open Access |
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Notes |
; Belgian Science Policy Office (BELSPO), Grant/Award Number: WE/49/N14-O14 ; |
Approved |
Most recent IF: 3.469 |
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Call Number |
UA @ admin @ c:irua:148760 |
Serial |
5781 |
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| Permanent link to this record |
