Records |
Author |
Alvarez-Martin, A.; Trashin, S.; Cuykx, M.; Covaci, A.; De Wael, K.; Janssens, K. |
Title |
Photodegradation mechanisms and kinetics of Eosin-Y in oxic and anoxic conditions |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Dyes and pigments |
Abbreviated Journal |
Dyes Pigments |
Volume |
145 |
Issue |
|
Pages |
376-384 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
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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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000405972900046 |
Publication Date |
2017-06-16 |
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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 |
Impact Factor |
3.473 |
Times cited |
18 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.473 |
Call Number |
UA @ admin @ c:irua:144385 |
Serial |
5770 |
Permanent link to this record |
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Author |
Lybaert, J.; Tehrani, K.A.; De Wael, K. |
Title |
Mediated electrolysis of vicinal diols by neocuproine palladium catalysts |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
Volume |
247 |
Issue |
|
Pages |
685-691 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY) |
Abstract |
Synthetic electrochemistry agrees well with the principles of sustainable chemistry, therefore it is considered as a more environmentally friendly approach than some current synthetic methods Here, we present a new strategy for the chemoselective oxidation of vicinal diols, viz. the integration of neocuproine palladium catalysts and electrosynthesis. Benzoquinones are used as an effective mediator as the reduced species (hydroquinones) can be easily reoxidized at relative low potentials at an electrode surface. NeocuproinePd(OAc)2 efficiently works as a catalyst in an electrolysis reaction for vicinal diols at room temperature. This is a remarkable observation given the fact that aerobic oxidation reactions of alcohols typically need a more complex catalyst, i.e. [neocuproinePdOAc]2[OTf]2. In this article we describe the optimization of the electrolysis conditions for the neocuproinePd(OAc)2 catalyst to selectively oxidize diols. The suggested approach leads to conversion of alcohols with high yields and provides an interesting alternative to perform oxidation reactions under mild conditions by the aid of electrochemistry. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000408582300072 |
Publication Date |
2017-07-08 |
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 |
Impact Factor |
4.798 |
Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.798 |
Call Number |
UA @ admin @ c:irua:144118 |
Serial |
5706 |
Permanent link to this record |
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Author |
Bottari, F.; De Wael, K. |
Title |
Electrodeposition of gold nanoparticles on boron doped diamond electrodes for the enhanced reduction of small organic molecules |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. |
Abbreviated Journal |
J Electroanal Chem |
Volume |
801 |
Issue |
|
Pages |
521-526 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The performance of gold nanoparticles electrodeposited on boron doped diamond (BDD) electrodes was investigated in respect to the reduction of chloramphenicol (CAP), an antibiotic of the phenicols family. The chosen deposition protocol, three nucleation-growing pulses, shows a remarkable surface coverage, with an even distribution of average-sized gold particles (~ 50 nm), and it was proven capable of generating a three-fold increase in the CAP reduction current. A calibration plot for CAP detection was obtained in the micromolar range (535 μM) with good correlation coefficient (0.9959) and an improved sensitivity of 0.053 μA μM− 1 mm− 2 compared to the electrochemistry of CAP at a bare BDD electrode. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000411847500065 |
Publication Date |
2017-08-02 |
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 |
1572-6657 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.012 |
Times cited |
4 |
Open Access |
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Notes |
; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation Flanders (FWO) (project G037415N). ; |
Approved |
Most recent IF: 3.012 |
Call Number |
UA @ admin @ c:irua:146372 |
Serial |
5600 |
Permanent link to this record |
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Author |
Eliaerts, J.; Dardenne, P.; Meert, N.; Van Durme, F.; Samyn, N.; Janssens, K.; De Wael, K. |
Title |
Rapid classification and quantification of cocaine in seized powders with ATR-FTIR and chemometrics |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Drug testing and analysis |
Abbreviated Journal |
Drug Test Anal |
Volume |
9 |
Issue |
10 |
Pages |
1480-1489 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Traditionally, fast screening for the presence of cocaine in unknown powders is performed by means of colour tests. The major drawbacks of these tests are subjective colour evaluation depending on the operator (50 shades of blue) and a lack of selectivity. An alternative fast screening technique is Fourier Transform InfraRed (FTIR) spectrometry. This technique provides spectra that are difficult to interpret without specialized expertise and showing a lack of sensitivity for the detection of cocaine in mixtures. To overcome these limitations, a portable FTIR spectrometer using Attenuated Total Reflectance (ATR) sampling was combined with a multivariate technique, called Support Vector Machines (SVM). Representative street drug powders (n = 482), seized during the period January 2013 to July 2015, and reference powders (n = 33) were used to build and validate a classification model (n = 515) and a quantification model (n = 378). Both models were compared with the conventional chromatographic techniques. The SVM classification model showed a high sensitivity, specificity and efficiency (99%). The SVM quantification model determined cocaine content with a root mean squared error of prediction (RMSEP) of 6% calculated over a wide working range from 4 to 99 w%. In conclusion, the developed models resulted in a clear output (cocaine detected or cocaine not detected) and a reliable estimation of the cocaine content in a wide variety of mixtures. The ATR-FTIR technique combined with SVM is a straightforward, user-friendly and fast approach for routine classification and quantification of cocaine in seized powders. |
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000413685200001 |
Publication Date |
2016-12-17 |
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 |
Impact Factor |
3.469 |
Times cited |
9 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.469 |
Call Number |
UA @ admin @ c:irua:139483 |
Serial |
5799 |
Permanent link to this record |
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Author |
Marchetti, A.; Pilehvar, S.; 't Hart, L.; Leyva Pernia, D.; Voet, O.; Anaf, W.; Nuyts, G.; Otten, E.; Demeyer, S.; Schalm, O.; De Wael, K. |
Title |
Indoor environmental quality index for conservation environments : the importance of including particulate matter |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Building and environment |
Abbreviated Journal |
Build Environ |
Volume |
126 |
Issue |
|
Pages |
132-146 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Systems and software Modelling (AnSyMo); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
It is commonly known that the conservation state of works of arts exhibited inside museums is strongly influenced by the indoor environmental quality (IEQ). Heritage institutions traditionally record and evaluate their IEQ by monitoring temperature, relative humidity, and -more rarely-light. However, smart use of technology enables monitoring other parameters that give a more complete insight in environmental air aggressiveness. One of this parameters is particulate matter (PM) and especially its concentration, size distribution and chemical composition. In this work, we present a selection of data sets which were obtained in a measuring campaign performed in the War Heritage Institute in Brussels, Belgium. A continuous monitoring of PM concentration with a light scattering based particle counter was performed. In addition the daily mass concentration and size distribution of airborne PM was monitored by means of Harvard impactors. The chemical composition of sampled PM was inferred from the results of XRF and IC analysis. The insights from these datasets are combined with the results of traditional environmental monitoring (temperature, relative humidity and light intensity), and assessed against the recommended guidelines for conservation environments. By using an integrated approach based on the calculation of an IEQ-index, we present a straightforward methodology to evaluate and visualize the IEQ including also continuous PM monitoring. It is clear from the results of this study how including PM in IEQ analysis allows to identify potential risks for museum collections that remain invisible when only traditional parameters are considered. |
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000417010000012 |
Publication Date |
2017-09-20 |
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 |
0360-1323 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.053 |
Times cited |
10 |
Open Access |
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Notes |
; The study was funded by UAntwerp, Belspo Brain BR/132/A6 and BR/154/A6. ; |
Approved |
Most recent IF: 4.053 |
Call Number |
UA @ admin @ c:irua:146371 |
Serial |
5661 |
Permanent link to this record |
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Author |
Pauwels, D.; Geboes, B.; Hereijgers, J.; Choukroun, D.; De Wael, K.; Breugelmans, T. |
Title |
The application of an electrochemical microflow reactor for the electrosynthetic aldol reaction of acetone to diacetone alcohol |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemical engineering research and design |
Abbreviated Journal |
Chem Eng Res Des |
Volume |
128 |
Issue |
|
Pages |
205-213 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
The design and application of an electrochemical micro-flow reactor for the aldol reaction of acetone to diacetone alcohol (DAA) is reported. The modular reactor could be readily disassembled and reassembled to change the electrodes, incorporate a membrane and remove possible obstructions. The productivity and efficiency was quantified. Using a platinum deposit as electrocatalyst or an inert glassy carbon electrode as working electrode, the maximum obtainable equilibrium concentration of ±15 m% was reached after a single pass up to a flow rate of 8 ml min−1, yielding 0.57 g min−1 DAA (3.46 mmol cm−3 min−1) at an efficiency of 0.33 g C−1 on platinum and 0.50 g min−1 (3.04 mmol cm−3 min−1) at 1.20 g C−1 on glassy carbon. Note that no optimisation studies have been made in the present paper. |
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000424736500018 |
Publication Date |
2017-10-20 |
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 |
0263-8762 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.538 |
Times cited |
2 |
Open Access |
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Notes |
; The authors would like to thank Bert De Mot for assisting with the measurements. Jonas Hereijgers greatly acknowledges the Research Foundation – Flanders (FWO) for support through a Post-Doctoral grant (12Q8817N). ; |
Approved |
Most recent IF: 2.538 |
Call Number |
UA @ admin @ c:irua:146943 |
Serial |
5871 |
Permanent link to this record |
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Author |
Hrdlickova Kuckova, S.; Hamidi-Asl, E.; Sofer, Z.; Marvan, P.; De Wael, K.; Sanyova, J.; Janssens, K. |
Title |
A simplified protocol for usage of new immuno-SERS probes for detection of casein, collagens and ovalbumin in cross-sections of artworks |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Analytical methods |
Abbreviated Journal |
Anal Methods-Uk |
Volume |
10 |
Issue |
9 |
Pages |
1054-1062 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Although it is now relatively straightforward to identify protein binders in works of art, their proper localization within the corresponding layer still represents a significant analytical challenge. Until now, the identification of proteins has mainly been performed by peptide mass fingerprinting using mass spectrometric methods and their localization in polished paint cross-sections have been realized by optical microscopy via the use of fluorescent stain Sypro Ruby (SR). In this work we propose a simplified protocol for immuno-surface enhanced Raman scattering (immuno-SERS) using gold nanoparticles attached to biphenyl-4,4-dithiol (BPDT) as the SERS-nanotag. These nanoparticles are easily obtainable in the lab and have been used to label multilayered mock up samples prepared as cross-sections to estimate the detection limits of the suggested method. The layers contain egg, casein, and different animal glues binders (prepared in various ratios with linseed oil or a carbohydrate component) mixed with the pigments azurite, vermilion and chalk. The sensitivity of staining agent SR is compared to that of the immuno-SERS protocol for the first time. |
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000426696100017 |
Publication Date |
2018-02-02 |
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 |
1759-9660 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.9 |
Times cited |
3 |
Open Access |
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Notes |
; The authors wish to acknowledge the Fund for Scientific Research-Flanders (FWO-Vlaanderen) for the support to act as a Postdoctoral Fellow – Pegasus of the Research Foundation – Flanders, and the grant from Specific University research (MSMT No. 20/2017) from the Czech Republic. This work was supported by the project Advanced Functional Nanorobots (reg. No. CZ.02.1.01/0.0/0.0/15_003/ 0000444 financed by the EFRR). Zdenek Sofer and Petr Marvan were supported by specific university research (MSMT No. 20-SVV/2018). ; |
Approved |
Most recent IF: 1.9 |
Call Number |
UA @ admin @ c:irua:148803 |
Serial |
5831 |
Permanent link to this record |
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Author |
Vermeulen, M.; Janssens, K.; Sanyova, J.; Rahemi, V.; McGlinchey, C.; De Wael, K. |
Title |
Assessing the stability of arsenic sulfide pigments and influence of the binding media on their degradation by means of spectroscopic and electrochemical techniques |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
Volume |
138 |
Issue |
138 |
Pages |
82-91 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In this paper, we used the semiconducting and lightfastness properties of synthetic and mineral arsenic sulfide pigments to study their stability by means of electrochemical and microfadometric techniques. A combination of these techniques shows that in the early stage of the degradation process, amorphous arsenic sulfides are more stable than both crystalline forms, while upon longer exposure time, amorphous pigments will fade more than both mineral pigments, making it less suitable. While the stability study was carried out on unbound pigments, the influence of the organic binder on the relative degradation of the arsenic sulfide pigments was investigated through a multi-analytical approach on pigment/binder mock-up paint samples. For this purpose, the formation of arsenic trioxide was assessed by micro Fourier transform infrared (μ-FTIR) spectroscopy while the influence of the binder on the formation of sulfates was studied by means of synchrotron radiation X-ray near edge structure (μ-XANES). Both techniques elucidate a higher stability of all pigments in gum arabic while the use of egg yolk as binder leads to the most degradation, most likely due to its sulfur-rich composition. In the context of the degradation of arsenic sulfide pigments, other binders such as animal glue, egg white or linseed oil show an intermediate impact. |
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000428103000010 |
Publication Date |
2018-01-06 |
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 |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.034 |
Times cited |
4 |
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” (grant number SD/RI/04A). We gratefully acknowledge Megane Willems (Institut Paul-Lambin) for her help with mu-FFIR analyses and realization of the mock-up paint samples. We acknowledge the Paul Scherrer Institut, Villigen, Switzerland for provision of synchrotron radiation beamtime at beamline Phoenix of the SLS. ; |
Approved |
Most recent IF: 3.034 |
Call Number |
UA @ admin @ c:irua:150149 |
Serial |
5482 |
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. |
Title |
Identifying intermediates in the reductive intramolecular cyclisation of allyl 2-bromobenzyl ether by an improved electron paramagnetic resonance spectroelectrochemical electrode design combined with density functional theory calculations |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
Volume |
271 |
Issue |
271 |
Pages |
10-18 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
The electrochemical activation of C-X bonds requires very negative electrode potentials. Lowering the overpotentials and increasing the catalytic activity requires intensive electrocatalytic research. A profound understanding of the reaction mechanism and the influence of the electrocatalyst allows optimal tuning of the electrocatalyst. This can be achieved by combining electrochemical techniques with electron paramagnetic resonance (EPR) spectroscopy. Although this was introduced in the mid-twentieth century, the application of this combined approach in electrocatalytic research is underexploited. Several reasons can be listed, such as the limited availability of EPR instrumentation and electrochemical devices for such in situ experiments. In this work, a simple and inexpensive construction adapted for in situ EPR electrocatalytic research is proposed. The proof of concept is provided by studying a model reaction, namely the reductive cyclisation of allyl 2-bromobenzyl ether which has interesting industrial applications. |
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000430369800002 |
Publication Date |
2018-03-20 |
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 |
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 |
Call Number |
UA @ admin @ c:irua:150463 |
Serial |
5652 |
Permanent link to this record |
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Author |
De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K. |
Title |
Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
90 |
Issue |
8 |
Pages |
5290-5297 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes. |
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000430512200049 |
Publication Date |
2018-02-23 |
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 |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
8 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:149528 |
Serial |
5693 |
Permanent link to this record |
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Author |
De Jong, M.; Florea, A.; Eliaerts, J.; Van Durme, F.; Samyn, N.; De Wael, K. |
Title |
Tackling poor specificity of cocaine color tests by electrochemical strategies |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
90 |
Issue |
11 |
Pages |
6811-6819 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
This paper presents electrochemical strategies for the fast screening of cocaine and most common cutting agents found in seized drug samples. First, a study on the performance of Scott color tests on cocaine and a wide range of cutting agents is described. The cutting agents causing false positive or false negative results when in mixture with cocaine are identified. To overcome the lack of specificity of color tests, we further propose a fast screening strategy by means of square wave voltammetry on disposable graphite screen printed electrodes, which reveals the unique fingerprint of cocaine and cutting agents. By employing a forward and backward scan and by a dual pH strategy, we enrich the electrochemical fingerprint and enable the simultaneous detection of cocaine and cutting agents. The effectiveness of the developed strategies was tested for the detection of cocaine in seized cocaine samples and compared with the color tests. Moreover, we prove the usefulness of square wave voltammetry for predicting possible interfering agents in color tests, based on the reduction peak of cobalt thiocyanate. The developed electrochemical strategies allow for a quick screening of seized cocaine samples resulting in a selective identification of drugs and cutting agents. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000434893200066 |
Publication Date |
2018-05-09 |
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 |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by Grants BR/314 /PI/APTADRU and IOF-SBO. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:151316 |
Serial |
5867 |
Permanent link to this record |
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Author |
Florea, A.; Cowen, T.; Piletsky, S.; De Wael, K. |
Title |
Polymer platforms for selective detection of cocaine in street samples adulterated with levamisole |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
Talanta |
Volume |
186 |
Issue |
186 |
Pages |
362-367 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Accurate drug detection is of utmost importance for fighting against drug abuse. With a high number of cutting agents and adulterants being added to cut or mask drugs in street powders the number of false results is increasing. We demonstrate for the first time the usefulness of employing polymers readily synthesized by electrodeposition to selectively detect cocaine in the presence of the commonly used adulterant levamisole. The polymers were selected by computational modelling to exhibit high binding affinity towards cocaine and deposited directly on the surface of graphene-modified electrodes via electropolymerization. The resulting platforms allowed a distinct electrochemical signal for cocaine, which is otherwise suppressed by levamisole. Square wave voltammetry was used to quantify cocaine alone and in the presence of levamisole. The usefulness of the platforms was demonstrated in the screening of real street samples. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000435048800049 |
Publication Date |
2018-04-25 |
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 |
0039-9140; 1873-3573 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.162 |
Times cited |
9 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement no. 753223 Narcoreader. This work was also supported by IOF-SBO (UAntwerp). The authors thank Gert Nuyts for the help with SEM analyses. ; |
Approved |
Most recent IF: 4.162 |
Call Number |
UA @ admin @ c:irua:151250 |
Serial |
5777 |
Permanent link to this record |
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Author |
Eliaerts, J.; Meert, N.; Van Durme, F.; Samyn, N.; De Wael, K.; Dardenne, P. |
Title |
Practical tool for sampling and fast analysis of large cocaine seizures |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Drug testing and analysis |
Abbreviated Journal |
Drug Test Anal |
Volume |
10 |
Issue |
6 |
Pages |
1039-1042 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000435270300016 |
Publication Date |
2018-02-03 |
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 |
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 |
Call Number |
UA @ admin @ c:irua:148760 |
Serial |
5781 |
Permanent link to this record |
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Author |
Sathiyamoorthy, S.; Girijakumari, G.; Kannan, P.; Venugopal, K.; Thiruvottriyur Shanmugam, S.; Veluswamy, P.; De Wael, K.; Ikeda, H. |
Title |
Tailoring the functional properties of polyurethane foam with dispersions of carbon nanofiber for power generator applications |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
Volume |
449 |
Issue |
449 |
Pages |
507-513 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
To produce effective thermoelectric nanocomposites, carbon nanofibers (CNF) incorporated polyurethane (PU) foams with nanocomposites are prepared via in-situ polymerization method to create a synergy that would produce a high thermopower. The formation mechanism of foams, the reaction kinetics, and the physical properties such as density and water absorption studied before and after CNF incorporation. The microscopy images showed a uniform dispersion of CNF in the PU matrix of the prepared foams. Spectroscopic studies such as X-ray photoelectron and laser Raman spectroscopy suggested the existence of a tight intermolecular binding interaction between the carbon nanofibers and the PU matrix in the prepared composite foams. It found that the thermopower is directly dependent on the concentration of carbon nanofiber since, with rising concentration of 1%3%, the coefficient values increased from 1.2 μV/K to 11.9 μV/K respectively, a value higher than that of earlier report. This unique nanocomposite offers a new opportunity to recycle waste heat in portable/wearable electronics and other applications, which will broaden the development of low weight and mechanical flexibility. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000438025400064 |
Publication Date |
2018-02-06 |
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 |
0169-4332 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.387 |
Times cited |
4 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.387 |
Call Number |
UA @ admin @ c:irua:151287 |
Serial |
5868 |
Permanent link to this record |
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Author |
Bottari, F.; Blust, R.; De Wael, K. |
Title |
Bio(inspired) strategies for the electro-sensing of β-lactam antibiotics |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
|
Volume |
10 |
Issue |
10 |
Pages |
143-148 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The dire previsions of the WHO on the so-called “post-antibiotic era” and the continuous and global rise of anti-microbial resistance, spurs our research community to find better ways to fight these threats. In light of this severe threat to human health many attempts have been made to develop efficient methods to detect antibiotic residues in different streams. The use of electrochemistry seems an inviting approach for on-site and fast monitoring. In this critical review, recent developments in the field of (bio) electro-sensing of 19-lactam antibiotics will be presented, with a focus on aptamers and molecularly imprinted polymers, the two main promises of a new generation of biosensors, yet to be fulfilled. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000442800000022 |
Publication Date |
2018-05-24 |
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 |
2451-9103; 2451-9111 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
15 |
Open Access |
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Notes |
; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation – Flanders (FWO). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:153744 |
Serial |
5488 |
Permanent link to this record |
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Author |
Kardel, F.; Wuyts, K.; De Wael, K.; Samson, R. |
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 |
Volume |
25 |
Issue |
26 |
Pages |
25994-26004 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000443329100034 |
Publication Date |
2018-07-02 |
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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.741 |
Times cited |
6 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.741 |
Call Number |
UA @ admin @ c:irua:153669 |
Serial |
5489 |
Permanent link to this record |
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Author |
Wuyts, K.; Hofman, J.; van Wittenberghe, S.; Nuyts, G.; De Wael, K.; Samson, R. |
Title |
A new opportunity for biomagnetic monitoring of particulate pollution in an urban environment using tree branches |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Atmospheric environment : an international journal |
Abbreviated Journal |
Atmos Environ |
Volume |
190 |
Issue |
190 |
Pages |
177-187 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Environmental magnetism, and the magnetic leaf signal in particular, is amply investigated and applied as proxy for atmospheric particulate matter pollution. In this study, we investigated the magnetic signal of annual segments of tree branches, and the composition of particles deposited hereon. Branches are, contrary to leaves of deciduous trees, available during leaf-off seasons and exposed to air pollution year-round. We examined the intra- and inter-tree variation in saturation isothermal remanent magnetization (SIRM) of branch internodes of London plane (Platanus x aeerifolia Willd.) trees in an urban environment. The branch SIRM, normalized by surface area, ranged from 18 to 650 x 10(-6) angstrom; the median amounted to 106 x 10(-6) angstrom. Most of the branch magnetic signal was attributed to the epidermis or bark, and the presence of metal-containing particles on the branch surfaces was confirmed by SEM-EDX. The location of the trees and the height, the depth in the crown and the age of the branches significantly influenced the branch SIRM. The median branch SIRM was up to 135% higher near a busy ring road than in quiet environments (city park and quiet street canyon), and was linked to the presence of Fe-rich particles with co-occurrence of trace metals such as Cr, Cu, Zn and Mn on the branch surface. Within the tree crowns, the branch SIRM generally decreased with increasing height, and was 22% higher in the interior than at the periphery of the crowns. Within the branches, the SIRM increased with each year of exposure, but did not relate to year-to-year variation in particle concentrations due to branch surface changes (epidermis shedding). Our results provide indications that branches can be a valuable alternative for biomagnetic monitoring of particulate pollution, but intra-tree variability in branch SIRM can be substantial due to the branch's location in the tree and branch age. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000444659400017 |
Publication Date |
2018-07-11 |
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 |
1352-2310 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.629 |
Times cited |
3 |
Open Access |
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Notes |
; We would like to thank the city council services of the city of Antwerp for their logistical support. We are grateful to Ana Castanheiro and Leen Van Ham for laboratory and SEM assistance. JH is supported as postdoctoral fellow of the Research Foundation Flanders (FWO; 12I4816N) and SVW is supported by a Marie Sklodowska-Curie Individual Fellowship under the grant agreement no 701815 FLUOPHOT. ; |
Approved |
Most recent IF: 3.629 |
Call Number |
UA @ admin @ c:irua:153607 |
Serial |
5454 |
Permanent link to this record |
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Author |
Tarakanov, P.A.; Tarakanova, E.N.; Dorovatovskii, P.V.; Zubavichus, Y.V.; Khrustalev, V.N.; Trashin, S.A.; De Wael, K.; Neganova, M.E.; Mischenko, D.V.; Sessler, J.L.; Stuzhin, P.A.; Pushkarev, V.E.; Tomilova, L.G. |
Title |
Optical readout of controlled monomer-dimer self-assembly |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
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Volume |
47 |
Issue |
40 |
Pages |
14169-14173 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
5,7-Substituted 1,4-diazepinoporphyrazine magnesium(II) complexes were synthesized via Mg(II)-alkoxide templated macrocyclization. A single crystal growth synchrotron diffraction analysis permitted what is to our knowledge the first structural characterization of a 1,4-diazepinoporphyrazine. It exists as a dimer in the solid state. In silico calculations supported by solution phase spectral studies involving a series of representative derivatives, provided insights into the factors governing dimerization of 1,4-diazepinoporphyrazines. The present 1,4-diazepinoporphyrazines serve as useful probes for understanding the determinants that guide dimermonomer equilibria and the self-assembly of phthalocyanine derivatives. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000447708900005 |
Publication Date |
2018-04-10 |
Series Editor |
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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 |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
4 |
Open Access |
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Notes |
; We thank Dr Alexander V. Chernyak for recording the NMR spectra. Synthetic and optical spectroscopic studies in this work were supported by the RSF (Grant 17-73-10413). NMR studies were supported by the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grant MD-2991.2017.3). SR-XRD studies were supported by the RUDN University Program “5-100”. We also acknowledge support of electrochemical, in vitro and in vivo studies by the State Assignment (Theme 45.5 Creation of compounds with given physicochemical properties) and the facilities provided by the Center of Collective Use of IPAC RAS (Chernogolovka, Russia). Single-crystal X-ray measurements have been performed at the unique scientific facility Kurchatov Synchrotron Radiation Source supported by the Ministry of Education and Science of the Russian Federation (project code RFMEFI61917X0007). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:151294 |
Serial |
5755 |
Permanent link to this record |
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Author |
Castanheiro, A.; Joos, P.; Wuyts, K.; De Wael, K.; Samson, R. |
Title |
Leaf-deposited semi-volatile organic compounds (SVOCs) : an exploratory study using GCxGC-TOFMS on leaf washing solutions |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Chemosphere |
Abbreviated Journal |
Chemosphere |
Volume |
214 |
Issue |
214 |
Pages |
103-110 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Airborne particulate matter (PM) includes semi-volatile organic compounds (SVOCs), which can be deposited on vegetation matrices such as plant leaves. In alternative to air-point measurements or artificial passive substrates, leaf monitoring offers a cost-effective, time-integrating means of assessing local air quality. In this study, leaf washing solutions from ivy (Hedera hibernica) leaves exposed during one-month at different land use classes were explored via comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS). The composition of leaf-deposited SVOCs, corrected for those of unexposed leaves, was compared against routinely monitored pollutants concentrations (PM10, PM2.5, O3, NO2, SO2) measured at co-located air monitoring stations. The first study on leaf-deposited SVOCs retrieved from washing solutions, herein reported, delivered a total of 911 detected compounds. While no significant land use (rural, urban, industrial, traffic, mixed) effects were observed, increasing exposure time (from one to 28 days) resulted in a higher number and diversity of SVOCs, suggesting cumulative time-integration to be more relevant than local source variations between sites. After one day, leaf-deposited SVOCs were mainly due to alcohols, N-containing compounds, carboxylic acids, esters and lactones, while ketones, diketones and hydrocarbons compounds gained relevance after one week, and phenol compounds after one month. As leaf-deposited SVOCs became overall more oxidized throughout exposure time, SVOCs transformation or degradation at the leaf surface is suggested to be an important phenomenon. This study confirmed the applicability of GCxGC-TOFMS to analyze SVOCs from leaf washing solutions, further research should include validation of the methodology and comparison with atmospheric organic pollutants. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000449891300013 |
Publication Date |
2018-09-13 |
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Abbreviated Series Title |
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Edition |
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ISSN |
0045-6535; 1879-1298 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.208 |
Times cited |
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Open Access |
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Notes |
; The authors thank the Flemish Environment Agency (VMM) for their collaboration and air quality data; Sam Dekkers and Jonathan Van Waeyenbergh for their help with sample collection. The study was performed using a study set-up funded by the Special Research Fund of the University of Antwerp (KPBOF 2014, no. FFB 140090 'Tree leaf surface properties as dynamic drivers of particulate matter-leaf interaction and phyllosphere microbial communities'). A.C. acknowledges the Research Foundation Flanders (FWO) for her SB PhD fellowship. ; |
Approved |
Most recent IF: 4.208 |
Call Number |
UA @ admin @ c:irua:153509 |
Serial |
5692 |
Permanent link to this record |
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Author |
Florea, A.; De Jong, M.; De Wael, K. |
Title |
Electrochemical strategies for the detection of forensic drugs |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
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Volume |
11 |
Issue |
11 |
Pages |
34-40 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Illicit drugs consumption and trafficking is spread worldwide and remains an increasing challenge for local authorities. Forensic drugs and their metabolites are released into wastewaters due to human excretion after illegal consumption of drugs and occasionally due to disposal of clandestine laboratory wastes into sewage systems, being recently classified as the latest group of emerging pollutants. Hence, it is essential to have efficient and accurate methods to detect these type of compounds in seized street samples, biological fluids and wastewaters in order to reduce and prevent trafficking and consumption and negative effects on aquatic systems. Electrochemical strategies offer a fast, portable, low-cost and accurate alternative to chromatographic and spectrometric methods, for the analysis of forensic drugs and metabolites in different matrices. Recent electrochemical strategies applied to the detection of illicit drugs in wastewaters, biological fluids and street samples are presented in this review, together with the impact of drug consumption on the environment. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000453710900007 |
Publication Date |
2018-07-21 |
Series Editor |
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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 |
2451-9103; 2451-9111 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
7 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge financial support from BELSPO, IOF-SBO and UAntwerp. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:152366 |
Serial |
5597 |
Permanent link to this record |
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Author |
Rahemi, V.; Trashin, S.; Hafideddine, Z.; Meynen, V.; Van Doorslaer, S.; De Wael, K. |
Title |
Enzymatic sensor for phenols based on titanium dioxide generating surface confined ROS after treatment with H2O2 |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
Volume |
283 |
Issue |
283 |
Pages |
343-348 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Titanium dioxide (TiO2) is a popular material as host matrix for enzymes. We now evidence that TiO2 can accumulate and retain reactive oxygen species after treatment by hydrogen peroxide (H2O2) and support redox cycling of a phenolic analyte between horseradish peroxidase (HRP) and an electrode. The proposed detection scheme is identical to that of second generation biosensors, but the measuring solution requires no dissolved H2O2. This significantly simplifies the analysis and overcomes issues related to H2O2 being present (or generated) in the solution. The modified electrodes showed rapid stabilization of the baseline, a low noise level, fast realization of a steady-state current response, and, in addition, improved sensitivity and limit of detection compared to the conventional approach, i.e. in the presence of H2O2 in the measuring solution. Hydroquinone, 4-aminophenol, and other phenolic compounds were successfully detected at sub-μM concentrations. Particularly, a linear response in the concentration range between 0.025 and 2 μM and LOD of 24 nM was demonstrated for 4-aminophenol. The proposed sensor design goes beyond the traditional concept with three sensors generations offering a new possibility for the development of enzymatic sensors based on peroxidases and the formation of ROS on titania after treatment with H2O2. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000455854000043 |
Publication Date |
2018-12-10 |
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 |
|
ISSN |
0925-4005 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.401 |
Times cited |
1 |
Open Access |
|
Notes |
; The authors thank the University of Antwerp for GOA funding and the Scientific Research-Flanders (FWO) (grant 12T4219N). V. Rahemi is financially supported through a postdoctoral fellowship of the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 5.401 |
Call Number |
UA @ admin @ c:irua:155665 |
Serial |
5605 |
Permanent link to this record |
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Author |
Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. |
Title |
Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
91 |
Issue |
3 |
Pages |
2035-2041 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
Electrochemistry and exploiting electrochemical fingerprints is a potent approach to address newly emerging surveillance needs, for instance for antibiotics. However, a comprehensive insight in the electrochemical oxidation behaviour and mechanism is re-quired for this sensing strategy. To address the lack in knowledge of the voltammetric behaviour of the cephalosporins antibiotics, a selection of cephalosporin antibiotics and two main intermediates were subjected to an electrochemical study of their redox behaviour by means of pulsed voltammetric techniques and small-scale electrolysis combined with HPLC-MS/MS analyses. Sur-prisingly, the detected oxidation products did not fit the earlier suggested oxidation of the sulfur group to the corresponding sul-foxide. The influence of different side chains, both at the three and the seven position of the β-lactam core structure on the elec-trochemical fingerprint were investigated. Additional oxidation signals at lower potentials were elucidated and linked to different side chains. These signals were further exploited to allow simultaneous detection of different cephalosporins in one voltammetric sweep. These fundamental insights can become the building blocks for an new on-site screening method. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000458220300055 |
Publication Date |
2019-01-03 |
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 |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
6 |
Open Access |
|
Notes |
; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:156046 |
Serial |
5497 |
Permanent link to this record |
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Author |
Kosov, A.D.; Dubrinina, T.V.; Borisova, N.E.; Ivanov, A.V.; Drozdov, K.A.; Trashin, S.A.; De Wael, K.; Kotova, M.S.; Tomilova, L.G. |
Title |
Novel phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements : optimized synthetic protocols and physicochemical properties |
Type |
A1 Journal article |
Year |
2019 |
Publication |
New journal of chemistry |
Abbreviated Journal |
New J Chem |
Volume |
43 |
Issue |
7 |
Pages |
3153-3161 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Novel synthetic protocols based on both template and multi-step methods were developed for phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements (Y, Eu, Gd, Dy, Er and Lu). p-Hydroquinone was employed as a reaction medium and as a reducing agent in the process of porphyrazine macrocycle formation. Both thermal and microwave irradiation techniques were successfully applied for activation of the template macrocyclization process. An alternative multi-step approach involving the initial stage of free-base ligand formation was realized for the lutetium compound. The target complexes were identified by high-resolution mass spectrometry, infrared spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Electrochemical behavior in solution and UV-vis absorbance in solutions and films were studied as well. Shifts in the position of the Q band and oxidationreduction potentials in comparison with corresponding phthalocyanine analogues were noticed. Using the IR absorption spectra recorded in the temperature range of 170300 K, the position of the Fermi level of −4.7 ± 0.1 eV and a characteristic energy diagram were obtained for the erbium complex. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000459944500035 |
Publication Date |
2019-01-23 |
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 |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.269 |
Times cited |
1 |
Open Access |
|
Notes |
; We are grateful for main financial support from the Russian Foundation for Basic Research (Grant No. 16-33-60005 and 18-33-00519). Investigation of optical properties was supported by the Russian Science Foundation (Grant 17-13-01197). Electrochemical investigations were supported by ERA.Net RUS Plus Plasmon Electrolight and FWO funding (RFBR No. 18-53-76006 ERA). We also thank the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grants MK-3115.2018.3) and partial support from the framework of the State Assignment of 2019 (Theme 45.5 Creation of compounds with given physicochemical properties). Investigation of electrophysical properties was supported by the RFBR (Grant 16-07-00961). K. A. Drozdov and M. S. Kotova thank Prof. L. I. Ryabova for productive discussion of the electrophysical data. ; |
Approved |
Most recent IF: 3.269 |
Call Number |
UA @ admin @ c:irua:156555 |
Serial |
5750 |
Permanent link to this record |
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Author |
Gaetani, C.; Gheno, G.; Borroni, M.; De Wael, K.; Moretto, L.M.; Ugo, P. |
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 |
Volume |
312 |
Issue |
312 |
Pages |
72-79 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000468595500008 |
Publication Date |
2019-04-29 |
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 |
|
ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.798 |
Times cited |
2 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 4.798 |
Call Number |
UA @ admin @ c:irua:159573 |
Serial |
5743 |
Permanent link to this record |
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Author |
Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K. |
Title |
Electrochemical strategies for adulterated heroin samples |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
91 |
Issue |
12 |
Pages |
7920-7928 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Electrochemical strategies to selectively detect heroin in street samples without the use of complicated electrode modifications were developed for the first time. For this purpose, heroin, mixing agents (adulterants, cutting agent, and impurities), and their binary mixtures were subjected to square wave voltammetry measurements at bare graphite electrodes at pH 7.0 and pH 12.0, in order to elucidate the unique electrochemical fingerprint of heroin and mixing agents as well as possible interferences or reciprocal influences. Adjusting the pH from pH 7.0 to pH 12.0 allowed a more accurate detection of heroin in the presence of most common mixing agents. Furthermore, the benefit of introducing a preconditioning step prior to running square wave voltammetry on the electrochemical fingerprint enrichment was explored. Mixtures of heroin with other drugs (cocaine, 3,4-methylenedioxymethamphetamine, and morphine) were also tested to explore the possibility of their discrimination and simultaneous detection. The feasibility of the proposed electrochemical strategies was tested on realistic heroin street samples from forensic cases, showing promising results for fast, on-site detection tools of drugs of abuse. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000472682000056 |
Publication Date |
2019-05-30 |
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 |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
2 |
Open Access |
|
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge IOF (UAntwerp) and Belspo for financial support. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:160061 |
Serial |
5596 |
Permanent link to this record |
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Author |
Florea, A.; Cowen, T.; Piletsky, S.; De Wael, K. |
Title |
Electrochemical analysis of cocaine in real samples based on electrodeposited biomimetic affinity ligands |
Type |
A1 Journal article |
Year |
2019 |
Publication |
The analyst |
Abbreviated Journal |
Analyst |
Volume |
144 |
Issue |
15 |
Pages |
4639-4646 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A selective electrochemical sensor for direct detection of cocaine was developed based on molecularly imprinted polymers electropolymerized onto graphene-modified electrodes. Palladium nanoparticles were integrated in the sensing layer for the benefit of enhancing the communication between imprinted sites and electrode and improving their homogenous distribution. The molecularly imprinted polymer was synthesized by cyclic voltammetry using p-aminobenzoic acid as high affinity monomer selected by computational modeling, and cocaine as template molecule. Experimental parameters related to the electrochemical deposition of palladium nanoparticles, pH, composition of electropolymerization mixture, extraction and rebinding condition were studied and optimized. Under optimized conditions the oxidation peak current varied linearly with cocaine concentration in the range of 100-500 µM, with a detection limit of 50 µM (RSD 0.71%, n=3). The molecularly imprinted sensor was able to detect cocaine in saliva and river water with good recoveries after sample pretreatment and was successfully applied for screening real street samples for cocaine. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000476812000021 |
Publication Date |
2019-06-10 |
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 |
0003-2654 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.885 |
Times cited |
3 |
Open Access |
|
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. ; |
Approved |
Most recent IF: 3.885 |
Call Number |
UA @ admin @ c:irua:160062 |
Serial |
5586 |
Permanent link to this record |
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Author |
Moro, G.; Bottari, F.; Sleegers, N.; Florea, A.; Cowen, T.; Moretto, L.M.; Piletsky, S.; De Wael, K. |
Title |
Conductive imprinted polymers for the direct electrochemical detection of beta-lactam antibiotics: The case of cefquinome |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
Volume |
297 |
Issue |
297 |
Pages |
126786 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A biomimetic sensor for cefquinome (CFQ) was designed at multi-walled carbon nanotubes modified graphite screen-printed electrodes (MWCNTs-G-SPEs) as a proof-of-concept for the creation of a sensors array for beta-lactam antibiotics detection in milk. The sensitive and selective detection of antibiotic residues in food and environment is a fundamental step in the elaboration of prevention strategies to fight the insurgence of antimicrobial resistance (AMR) as recommended by authorities around the world (EU, WHO, FDA). The detection strategy is based on the characteristic electrochemical fingerprint of the target antibiotic cefquinome. A conducive electropolymerized molecularly imprinted polymer (MIP) coupled with MWCNTs was found to be the optimal electrode modifier, able to provide an increased selectivity and sensitivity for CFQ detection. The design of CFQ-MIP was facilitated by the rational selection of the monomer, 4-aminobenzoic acid (4-ABA). The electropolymerization process of 4-ABA have not been fully elucidated yet; for this reason a thorough study and optimization of electropolymerization conditions was performed to obtain a conducive and stable poly(4-ABA) film. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and cyclic voltammetry (CV). CFQ-MIP were synthesized at MWCNT-G-SPEs by electropolyrnerization in pH approximate to 1 (0.1 M sulphuric acid) with a monomer:template ratio of 5:1. Two different analytical protocols were tested (single and double step detection) to minimize unspecific adsorptions and improve the sensitivity. Under optimal conditions, the lowest CFQ concentration detectable by square wave voltammetry (SWV) at the modified sensor was 50 nM in 0.1 M phosphate buffer pH 2. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000478562700020 |
Publication Date |
2019-07-08 |
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 |
|
ISSN |
0925-4005 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.401 |
Times cited |
4 |
Open Access |
|
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223. This work was also supported by FWO. ; |
Approved |
Most recent IF: 5.401 |
Call Number |
UA @ admin @ c:irua:161777 |
Serial |
5549 |
Permanent link to this record |
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Author |
Neven, L.; Thiruvottriyur Shanmugam, S.; Rahemi, V.; Trashin, S.; Sleegers, N.; Carrion, E.N.; Gorun, S.M.; De Wael, K. |
Title |
Optimized photoelectrochemical detection of essential drugs bearing phenolic groups |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
91 |
Issue |
15 |
Pages |
9962-9969 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The World Health Organization (WHO) model “List of Essential Medicines” includes among indispensable medicines antibacterials and pain and migraine relievers. Monitoring their concentration in the environment, while challenging, is important in the context of antibiotic resistance as well as their production of highly toxic compounds via hydrolysis. Traditional detection methods such as high-performance liquid chromatography (HPLC) or LC combined with tandem mass spectrometry or UV-vis spectroscopy are time-consuming, have a high cost, require skilled operators and are difficult to adapt for field operations. In contrast, (electrochemical) sensors have elicited interest because of their rapid response, high selectivity, and sensitivity as well as potential for on-site detection. Previously, we reported a novel sensor system based on a type II photosensitizer, which combines the advantages of enzymatic sensors (high sensitivity) and photoelectrochemical sensors (easy baseline subtraction). Under red-light illumination, the photosensitizer produces singlet oxygen which oxidizes phenolic compounds present in the sample. The subsequent reduction of the oxidized phenolic compounds at the electrode surface gives rise to a quantifiable photocurrent and leads to the generation of a redox cycle. Herein we report the optimization in terms of pH and applied potential of the photoelectrochemical detection of the hydrolysis product of paracetamol, i.e., 4-aminophenol (4-AP), and two antibacterials, namely, cefadroxil (CFD, beta-lactam antibiotic) and doxycycline (DXC, tetracycline antibiotic). The optimized conditions resulted in a detection limit of 0.2 mu mol L-1 for DXC, but in a 10 times higher sensitivity, 20 nmol L-1, for CFD. An even higher sensitivity, 7 nmol L-1, was noted for 4-AP. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000480499200086 |
Publication Date |
2019-06-25 |
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 |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
2 |
Open Access |
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Notes |
; FWO and UA-BOF are acknowledged for financial support. The Center for Functional Materials of Seton Hall University is thanked for support (S.M.G. and E.N.C.). Joren Van Loon is thanked for the graphical abstract. This research was supported by the medium scale research infrastructure funding Hercules funding (SEM). ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:161831 |
Serial |
5763 |
Permanent link to this record |
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Author |
Bottari, F.; Moro, G.; Sleegers, N.; Florea, A.; Cowen, T.; Piletsky, S.; van Nuijs, A.L.N.; De Wael, K. |
Title |
Electropolymerized o-phenylenediamine on graphite promoting the electrochemical detection of nafcillin |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Electroanalysis |
Abbreviated Journal |
Electroanal |
Volume |
32 |
Issue |
32 |
Pages |
135-141 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
By combining molecular modelling and electrochemistry we envision the creation of modified electrodes tailored for a more sensitive and selective detection of a single analyte. In this study we report on a graphite screen printed electrode modified with electropolymerized o-phenylenediamine, selected by rational design, which promotes the detection of nafcillin (NAF), an antibiotic. Parameters such as monomer concentration, pH and number of electropolymerization cycles were optimized to obtain the highest current signal for the target upon amperometric detection. NAF identification was based on the redox process at +1.1 V (vs pseudo Ag), ascribed to the oxidation of the C-7 side chain. With the optimized modification protocol, a two-fold increase in nafcillin signal could be obtained: the calibration plot in 0.1 M Britton-Robinson buffer pH 4 showed a limit of detection of 80 nM with improved sensitivity and reproducibility (RSD<5 %) compared to the detection at non-modified electrodes. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000482596300001 |
Publication Date |
2019-08-26 |
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 |
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 |
Call Number |
UA @ admin @ c:irua:162870 |
Serial |
5601 |
Permanent link to this record |
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Author |
Meysman, F.J.R.; Cornelissen, R.; Trashin, S.; Bonne, R.; Hidalgo-Martinez, S.; van der Veen, J.; Blom, C.J.; Karman, C.; Hou, J.-L.; Eachambadi, R.T.; Geelhoed, J.S.; De Wael, K.; Beaumont, H.J.E.; Cleuren, B.; Valcke, R.; van der Zant, H.S.J.; Boschker, H.T.S.; Manca, J.V. |
Title |
A highly conductive fibre network enables centimetre-scale electron transport in multicellular cable bacteria |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
10 |
Issue |
10 |
Pages |
4120 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Biological electron transport is classically thought to occur over nanometre distances, yet recent studies suggest that electrical currents can run along centimetre-long cable bacteria. The phenomenon remains elusive, however, as currents have not been directly measured, nor have the conductive structures been identified. Here we demonstrate that cable bacteria conduct electrons over centimetre distances via highly conductive fibres embedded in the cell envelope. Direct electrode measurements reveal nanoampere currents in intact filaments up to 10.1 mm long (>2000 adjacent cells). A network of parallel periplasmic fibres displays a high conductivity (up to 79 S cm(-1)), explaining currents measured through intact filaments. Conductance rapidly declines upon exposure to air, but remains stable under vacuum, demonstrating that charge transfer is electronic rather than ionic. Our finding of a biological structure that efficiently guides electrical currents over long distances greatly expands the paradigm of biological charge transport and could enable new bio-electronic applications. |
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Wos ![sorted by Wos field, ascending order (up)](img/sort_asc.gif) |
000485216900006 |
Publication Date |
2019-09-11 |
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 |
2041-1723 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
10 |
Open Access |
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Notes |
; This research was financially supported by the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) through ERC Grant 306933 (F.J.R.M.), the Research Foundation Flanders (FWO project grant G031416N), and the Netherlands Organisation for Scientific Research (VICI grant 016.VICI.170.072 to F.J.R.M.). H.J.E.B., C.J.B. and H.S.J.Z. were supported by the Netherlands Organisation for Scientific Research (NWO/OCW), as part of the Frontiers of Nanoscience program. R.B. is supported by an 'aspirant' grant from Research Foundation Flanders (FWO). We thank Laurine Burdorf (UAntwerpen) for help with Thiothrix cultivation, Marlies Nijemeisland (Faculty of Aerospace, TU Delft) for assistance with Raman microscopy, and Jan D'Haen (UHasselt) and Renaat Dasseville (UGent) for help with EM imaging. ; |
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:162795 |
Serial |
5451 |
Permanent link to this record |