Records |
Author |
Thiruvottriyur Shanmugam, S.; Trashin, S.; De Wael, K. |
Title |
Singlet oxygen-based photoelectrochemical detection of DNA |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Biosensors and bioelectronics |
Abbreviated Journal |
|
Volume |
195 |
Issue |
|
Pages |
113652 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
The current work, designed for the photoelectrochemical detection of DNA, evaluates light-responsive DNA probes carrying molecular photosensitizers generating singlet oxygen (1O2). We take advantage of their chromophore’s ability to produce 1O2 upon photoexcitation and subsequent photocurrent response. Type I, fluorescent and type II photosensitizers were studied using diode lasers at 406 nm blue, 532 nm green and 659 nm red lasers in the presensce and absence of a redox reporter, hydroquinone (HQ). Only type II photosensitizers (producing 1O2) resulted in a noticeable photocurrent in 1–4 nA range upon illumination, in particular, dissolved DNA probes labeled with chlorin e6 and erythrosine were found to give a well-detectable photocurrent response in the presence of HQ. Whereas, Type I photosensitizers and fluorescent chromophores generate negligible photocurrents (<0.15 nA). The analytical performance of the sensing system was evaluated using a magnetic beads-based DNA assay on disposable electrode platforms, with a focus to enhance the sensitivity and robustness of the technique in detecting complementary DNA targets. Amplified photocurrent responses in the range of 70–100 nA were obtained and detection limits of 17 pM and 10 pM were achieved using magnetic beads-captured chlorin e6 and erythrosine labeled DNA probes respectively. The presented novel photoelectrochemical detection can further be optimized and employed in applications for which enzymatic amplification such as polymerase chain reaction (PCR) is not applicable owing to their limitations and as an effective alternative to colorimetric detection when rapid detection of specific nucleic acid targets is required. |
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Wos |
000705223300003 |
Publication Date |
2021-09-23 |
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 |
0956-5663 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:181796 |
Serial |
8930 |
Permanent link to this record |
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Author |
Pankratov, D.; Hidalgo Martinez, S.; Karman, C.; Gerzhik, A.; Gomila, G.; Trashin, S.; Boschker, H.T.S.; Geelhoed, J.S.; Mayer, D.; De Wael, K.; Meysman, F.J.R. |
Title |
The organo-metal-like nature of long-range conduction in cable bacteria |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
|
Volume |
157 |
Issue |
|
Pages |
108675-10 |
Keywords |
A1 Journal article |
Abstract |
Cable bacteria are filamentous, multicellular microorganisms that display an exceptional form of biological electron transport across centimeter-scale distances. Currents are guided through a network of nickel-containing protein fibers within the cell envelope. Still, the mechanism of long-range conduction remains unresolved. Here, we characterize the conductance of the fiber network under dry and wet, physiologically relevant, conditions. Our data reveal that the fiber conductivity is high (median value: 27 S cm−1; range: 2 to 564 S cm−1), does not show any redox signature, has a low thermal activation energy (Ea = 69 ± 23 meV), and is not affected by humidity or the presence of ions. These features set the nickel-based conduction mechanism in cable bacteria apart from other known forms of biological electron transport. As such, conduction resembles that of an organic semi-metal with a high charge carrier density. Our observation that biochemistry can synthesize an organo-metal-like structure opens the way for novel bio-based electronic technologies. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2024-02-25 |
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 |
|
ISSN |
1567-5394 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 5; 2024 IF: 3.346 |
Call Number |
UA @ admin @ c:irua:205117 |
Serial |
9215 |
Permanent link to this record |
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Author |
Campos, R.; Thiruvottriyur Shanmugam, S.; Daems, E.; Ribeiro, R.; De Wael, K. |
Title |
Development of an electrochemiluminescent oligonucleotide-based assay for the quantification of prostate cancer associated miR-141-3p in human serum |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
|
Volume |
153 |
Issue |
|
Pages |
108495-108496 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
MicroRNAs (miRNAs) are small oligonucleotides (18–25 bases), biologically relevant for epigenetic regulation of key processes, particularly in association with cancer. Research effort has therefore been directed towards the monitoring and detection of miRNAs to progress (early) cancer diagnoses. Traditional detection strategies for miRNAs are expensive, with a lengthy time-to-result. In this study we develop an oligonucleotide-based assay using electrochemistry for the specific, selective and sensitive detection of a circulating miRNA (miR-141) associated with prostate cancer. In the assay, the excitation and readout of the signal are independent: an electrochemical stimulation followed by an optical readout. A ‘sandwich’ approach is incorporated, consisting of a biotinylated capture probe immobilised on streptavidin-functionalised surfaces and a detection probe labelled with digoxigenin. We show that the assay allows the detection of miR-141 in human serum, even in the presence of other miRNAs, with a LOD of 0.25 pM. The developed electrochemiluminescent assay has, therefore, the potential for efficient universal oligonucleotide target detection via the redesign of capture and detection probes. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
001031760700001 |
Publication Date |
2023-06-30 |
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 |
|
ISSN |
1567-5394 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
5 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 01.01.2024 |
Notes |
|
Approved |
Most recent IF: 5; 2023 IF: 3.346 |
Call Number |
UA @ admin @ c:irua:197615 |
Serial |
8849 |
Permanent link to this record |
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Author |
Moro, G.; Campos, R.; Daems, E.; Moretto, L.M.; De Wael, K. |
Title |
Haem-mediated albumin biosensing : towards voltammetric detection of PFOA |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
|
Volume |
152 |
Issue |
|
Pages |
108428-7 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
The haem group is a promising redox probe for the design of albumin-based voltammetric sensors. Among the endogenous ligands carried by human serum albumin (hSA), haem is characterised by a reversible redox behaviour and its binding kinetics strongly depend on hSA’s conformation, which, in turn, depends on the presence of other ligands. In this work, the potential applicability of haem, especially hemin, as a redox probe was first tested in a proof-of-concept study using perfluorooctanoic acid (PFOA) as model analyte. PFOA is known to bind hSA by occupying Sudlow’s I site (FA7) which is spatially related to the haem-binding site (FA1). The latter undergoes a conformational change, which is expected to affect hemin’s binding kinetics. To verify this hypothesis, hemin:albumin complexes in the presence/absence of PFOA were first screened by UV–Vis spectroscopy. Once the complex formation was verified, haem was further characterised via electrochemical methods to estimate its electron transfer kinetics. The hemin:albumin:PFOA system was studied in solution, with the aim of describing the multiple equilibria at stake and designing an electrochemical assay for PFOA monitoring. This latter could be integrated with protein-based bioremediation approaches for the treatment of per- and polyfluoroalkyl substances polluted waters. Overall, our preliminary results show how hemin can be applied as a redox probe in albumin-based voltammetric sensing strategies. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000971630400001 |
Publication Date |
2023-03-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1567-5394 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
5 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 5; 2023 IF: 3.346 |
Call Number |
UA @ admin @ c:irua:195069 |
Serial |
8876 |
Permanent link to this record |
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Author |
Borhani, A.H.; Berghmans, H.; Trashin, S.; De Wael, K.; Fago, A.; Moens, L.; Habibi-Rezaei, M.; Dewilde, S. |
Title |
Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Biochimica et biophysica acta : proteins and proteomics |
Abbreviated Journal |
Bba-Proteins Proteom |
Volume |
1854 |
Issue |
10a |
Pages |
1307-1316 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichiacoli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of − 0.13 V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06 V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000362307500008 |
Publication Date |
2015-05-22 |
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 |
1570-9639 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
2.773 |
Times cited |
|
Open Access |
|
Notes |
; This work was supported by the general grant for visiting scholar of the Ministry of Science, Research and Technology of I. R. Iran and by the University of Antwerp. ; |
Approved |
Most recent IF: 2.773; 2015 IF: 2.747 |
Call Number |
UA @ admin @ c:irua:125909 |
Serial |
5683 |
Permanent link to this record |
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Author |
Castanheiro, A.; Hofman, J.; Nuyts, G.; Joosen, S.; Spassov, S.; Blust, R.; Lenaerts, S.; De Wael, K.; Samson, R. |
Title |
Leaf accumulation of atmospheric dust : biomagnetic, morphological and elemental evaluation using SEM, ED-XRF and HR-ICP-MS |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Atmospheric Environment |
Abbreviated Journal |
Atmos Environ |
Volume |
221 |
Issue |
221 |
Pages |
117082 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Atmospheric dust deposition on plants enables the collection of site-specific particulate matter (PM). Knowing the morphology and composition of PM aids in disclosing their emitting sources as well as the associated human health risk. Therefore, this study aimed for a leaf-level holistic analysis of dust accumulation on plant leaves. Plant species (ivy and strawberry) with distinct leaf macro- and micro-morphology were exposed during 3 months at a moderate road traffic site in Antwerp, Belgium. Leaves collected every three weeks were analyzed for their magnetic signature, morphology and elemental content, by a combination of techniques (biomagnetic analyses, ED-XRF, HR-ICP-MS, SEM). Dust accumulation on the leaves was observed both visually (SEM) and magnetically, while the metal enrichment was limited (only evident for Cr) and more variable over time. Temporal dynamics during the second half of the exposure period, due to precipitation events and reduction of atmospheric pollution input, were evidenced in our results (elements/magnetically/SEM). Ivy accumulated more dust than strawberry leaves and seemed less susceptible to wash-off, even though strawberry leaves contain trichomes and a rugged micromorphology, leaf traits considered to be important for capturing PM. The magnetic enrichment (in small-grained, SD/PSD magnetite particles), on the other hand, was not species-specific, indicating a common contributing source. Variations in pollution contributions, meteorological phenomena, leaf traits, particle deposition (and encapsulation) versus micronutrients depletion, are discussed in light of the conducted monitoring campaign. Although not completely elucidative, the complex, multifactorial process of leaf dust accumulation can better be understood through a combination of techniques. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000503097100001 |
Publication Date |
2019-11-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
1352-2310 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5 |
Times cited |
|
Open Access |
|
Notes |
; The authors thank the Flemish Environment Agency (VMM) for their collaboration and air quality and meteorological data, and Karen Wuyts for the discussion about plant leaf characteristics. A.C. gratefully acknowledges the Research Foundation Flanders (FWO) for her PhD fellowship (1S21418N). J.H. received a FWO postdoctoral fellowship grant (1214816N). ; |
Approved |
Most recent IF: 5; 2020 IF: 3.629 |
Call Number |
UA @ admin @ c:irua:165458 |
Serial |
5691 |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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 |
|
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 |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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 |
|
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 |
Van Hal, M.; Campos, R.; Lenaerts, S.; De Wael, K.; Verbruggen, S.W. |
Title |
Gas phase photofuel cell consisting of WO₃- and TiO₂-photoanodes and an air-exposed cathode for simultaneous air purification and electricity generation |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Applied Catalysis B-Environmental |
Abbreviated Journal |
Appl Catal B-Environ |
Volume |
292 |
Issue |
|
Pages |
120204 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Research has shown the potential of photofuel cells (PFCs) for waste water treatment, enabling the (partial) recovery of the energy released from the degraded compounds as electricity. Literature on PFCs targeting air pollution on the other hand is extremely scarce. In this work an autonomously operating air purification device targeting sustainable electricity generation is presented. Knowledge on gas phase operation of PFCs was gathered by combining photocatalytic and photoelectrochemical measurements, both for TiO2 and WO3-based photocatalysts. While TiO2-based photocatalysts performed better in direct photocatalytic experiments, they were outperformed by WO3-based photoanodes in all-gas-phase PFC operation. Not only do WO3-based photocatalysts generate the highest steady state photocurrent, they also achieved the highest fuel-to-electricity conversion (>65 %). The discrepancies between gas phase photocatalytic and photoelectrochemical processes highlight the difference in driving material properties. This study serves as a proof-of-concept towards development of an autonomous, low-cost and widely applicable waste gas-to-electricity PFC device. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000663216500001 |
Publication Date |
2021-04-06 |
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 |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.446 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 9.446 |
Call Number |
UA @ admin @ c:irua:177075 |
Serial |
7989 |
Permanent link to this record |
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Author |
Neven, L.; Barich, H.; Sleegers, N.; Cánovas, R.; Debruyne, G.; De Wael, K. |
Title |
Development of a combi-electrosensor for the detection of phenol by combining photoelectrochemistry and square wave voltammetry |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Analytica chimica acta |
Abbreviated Journal |
|
Volume |
1206 |
Issue |
|
Pages |
339732 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
The high toxicity, endocrine-disrupting effects and low (bio)degradability commonly attributed to phenolic compounds have promoted their recognition as priority toxic pollutants. For this reason, the monitoring of these compounds in industrial, domestic and agricultural streams is crucial to prevent and decrease their toxicity in our daily life. To confront this relevant environmental issue, we propose the use of a combi-electrosensor which combines singlet oxygen (1O2)-based photoelectrochemistry (PEC) with square wave voltammetry (SWV). The high sensitivity of the PEC sensor (being a faster alternative for traditional COD measurements) ensures the detection of nmol L−1 levels of phenolic compounds while the SWV measurements (being faster than the color test kits) allow the differentiation between phenolic compounds. Herein, we report on the development of such a combi-electrosensor for the sensitive and selective detection of phenol (PHOH) in the presence of related phenolic compounds such as hydroquinone (HQ), bisphenol A (BPA), resorcinol (RC) and catechol (CC). The PEC sensor was able to determine the concentration of PHOH in spiked river samples containing only PHOH with a recovery between 96% and 111%. The SWV measurements elucidated the presence of PHOH, HQ and CC in the spiked samples containing multiple phenol compounds. Finally, the practicality of the combi-electrosensor set-up with a dual SPE containing two working electrodes and shared reference and counter electrodes was demonstrated. As a result, the combination of the two techniques is a powerful and valuable tool in the analysis of phenolic samples, since each technique improves the general performance by overcoming the inherent drawbacks that they display independently. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000793070200016 |
Publication Date |
2022-03-16 |
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 |
0003-2670; 1873-4324 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:187499 |
Serial |
8848 |
Permanent link to this record |
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Author |
Castanheiro, A.; Wuyts, K.; Hofman, J.; Nuyts, G.; De Wael, K.; Samson, R. |
Title |
Morphological and elemental characterization of leaf-deposited particulate matter from different source types : a microscopic investigation |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Environmental Science And Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
Volume |
28 |
Issue |
20 |
Pages |
25716-25732 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Particulate matter (PM) deposition on urban green enables the collection of particulate pollution from a diversity of contexts, and insight into the physico-chemical profiles of PM is key for identifying main polluting sources. This study reports on the morphological and elemental characterization of PM2-10 deposited on ivy leaves from five different environments (forest, rural, roadside, train, industry) in the region of Antwerp, Belgium. Ca. 40,000 leaf-deposited particles were thoroughly investigated by particle-based analysis using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX) and their physico-chemical characteristics were explored for PM source apportionment purposes. The size distribution of all deposited particles was biased towards small-sized PM, with 32% of the particles smaller than 2.5 mu m (PM2.5) and median diameters of 2.80-3.09 mu m. The source type influenced both the particles' size and morphology (aspect ratio and shape), with roadside particles being overall the smallest in size and the most spherical. While forest and rural elemental profiles were associated with natural PM, the industry particles revealed the highest anthropogenic metal input. PM2-10 profiles for roadside and train sites were rather comparable and only distinguishable when evaluating the fine (2-2.5 mu m) and coarse (2.5-10 mu m) PM fractions separately, which enabled the identification of a larger contribution of combustion-derived particles (small, circular, Fe-enriched) at the roadside compared to the train. Random forest prediction model classified the source type correctly for 61-85% of the leaf-deposited PM. The still modest classification accuracy denotes the influence of regional background PM and demands for additional fingerprinting techniques to facilitate source apportionment. Nonetheless, the obtained results demonstrate the utility of leaf particle-based analysis to fingerprint and pinpoint source-specific PM, particularly when considering both the composition and size of leaf-deposited particles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000609067300006 |
Publication Date |
2021-01-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.741 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.741 |
Call Number |
UA @ admin @ c:irua:176082 |
Serial |
8282 |
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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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000443329100034 |
Publication Date |
2018-07-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.741 |
Times cited |
6 |
Open Access |
|
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 |
't Hart, L.; Storme, P.; Anaf, W.; Nuyts, G.; Vanmeert, F.; Dorriné, W.; Janssens, K.; De Wael, K.; Schalm, O. |
Title |
Monitoring the impact of the indoor air quality on silver cultural heritage objects using passive and continuous corrosion rate assessments |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
Volume |
122 |
Issue |
10 |
Pages |
923-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
There is a long tradition in evaluating industrial atmospheres by measuring the corrosion rate of exposed metal coupons. The heritage community also uses this method, but the interpretation of the corrosion rate often lacks clarity due to the low corrosivity in indoor museum environments. This investigation explores the possibilities and drawbacks of different silver corrosion rate assessments. The corrosion rate is determined by three approaches: (1) chemical characterization of metal coupons using analytical techniques such as electrochemical measurements, SEM-EDX, XRD, and µ-Raman spectroscopy, (2) continuous corrosion monitoring methods based on electrical resistivity loss of a corroding nm-sized metal wire and weight gain of a corroding silver coated quartz crystal, and (3) characterization of the visual degradation of the metal coupons. This study confirms that subtle differences in corrosivity between locations inside a museum can be determined on condition that the same corrosion rate assessment is used. However, the impact of the coupon orientation with respect to the prevailing direction of air circulation can be substantially larger than the impact of the coupon location. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000384753800053 |
Publication Date |
2016-09-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0947-8396 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.455 |
Times cited |
3 |
Open Access |
|
Notes |
; This research has been sponsored by the Belgian Federal Public Planning Service Science Policy (BELSPO) under Project Number BR/132/A6/AIRCHECQ. In this project an innovative monitoring kit is developed that continuously and simultaneously measures both environmental parameters and material behaviour, enabling the study of the cause-effect relationships. The Quanta 250 FEG microscope at the University of Antwerp was funded by the Hercules foundation of the Flemish Government. ; |
Approved |
Most recent IF: 1.455 |
Call Number |
UA @ admin @ c:irua:135511 |
Serial |
5733 |
Permanent link to this record |
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Author |
de Jong, M.; Van Echelpoel, R.; Langley, A.R.; Eliaerts, J.; van den Berg, J.; De Wilde, M.; Somers, N.; Samyn, N.; De Wael, K. |
Title |
Real-time electrochemical screening of cocaine in lab and field settings with automatic result generation |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Drug testing and analysis |
Abbreviated Journal |
|
Volume |
14 |
Issue |
8 |
Pages |
1471-1481 |
Keywords |
A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
This work presents the results of a novel application for the fast on-site screening of cocaine and its main cutting agents in suspicious and confiscated samples. The methodology behind the novel application consists of portable electrochemical detection coupled with a peak-recognition algorithm for automated result output generation, validated both in laboratory and field settings. Currently used field tests, predominantly colorimetric tests, are lacking accuracy, often giving false positive or negative results. This presses the need for alternative approaches to field testing. By combining portable electrochemical approaches with peak-recognition algorithms, an accuracy of 98.4% concerning the detection of cocaine was achieved on a set of 374 powder samples. In addition, the approach was tested on multiple 'smuggled', colored cocaine powders and cocaine mixtures in solid and liquid states, typically in matrices such as charcoal, syrup and clothing. Despite these attempts to hide cocaine, our approach succeeded in detecting cocaine during on-site screening scenarios. This feature presents an advantage over colorimetric and optical detection techniques, which can fail with colored sample matrices. This enhanced accuracy on smuggled samples will lead to increased efficiency in confiscation procedures in the field, thus significantly reducing societal economic and safety concerns and highlighting the potential for electrochemical approaches in on-the-spot identification of drugs of abuse. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000790965700001 |
Publication Date |
2022-04-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1942-7603; 1942-7611 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:187767 |
Serial |
8921 |
Permanent link to this record |
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Author |
Schram, J.; Parrilla, M.; Sleegers, N.; Van Durme, F.; van den Berg, J.; van Nuijs, A.L.N.; De Wael, K. |
Title |
Electrochemical profiling and liquid chromatography–mass spectrometry characterization of synthetic cathinones : from methodology to detection in forensic samples |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Drug Testing And Analysis |
Abbreviated Journal |
Drug Test Anal |
Volume |
13 |
Issue |
7 |
Pages |
1282-1294 |
Keywords |
A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
The emergence of new psychoactive drugs in the market demands rapid and accurate tools for the on‐site classification of illegal and legal compounds with similar structures. Herein, a novel method for the classification of synthetic cathinones (SC) is presented based on their electrochemical profile. First, the electrochemical profile of five common SC (i.e., mephedrone, ethcathinone, methylone, butylone and 4‐chloro‐alpha‐pyrrolidinovalerophenone) is collected to build calibration curves using square wave voltammetry on graphite screen‐printed electrodes (SPE). Second, the elucidation of the oxidation pathways, obtained by liquid chromatography‐high resolution mass spectrometry, allows the pairing of the oxidation products to the SC electrochemical profile, providing a selective and robust classification. Additionally, the effect of common adulterants and illicit drugs on the electrochemical profile of the SC is explored. Interestingly, a cathodic pretreatment of the SPE allows the selective detection of each SC in presence of electroactive adulterants. Finally, the electrochemical approach is validated with gas‐chromatography‐mass spectrometry by analyzing 26 confiscated samples from seizures and illegal webshops. Overall, the electrochemical method exhibits a successful classification of SC including structural derivatives, a crucial attribute in an ever‐diversifying drug market. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000624902500001 |
Publication Date |
2021-02-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1942-7603; 1942-7611 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.469 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.469 |
Call Number |
UA @ admin @ c:irua:175583 |
Serial |
7863 |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000435270300016 |
Publication Date |
2018-02-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1942-7603; 1942-7611 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.469 |
Times cited |
1 |
Open Access |
|
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 |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000413685200001 |
Publication Date |
2016-12-17 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1942-7603; 1942-7611 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.469 |
Times cited |
9 |
Open Access |
|
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 |
Borah, R.; Ninakanti, R.; Nuyts, G.; Peeters, H.; Pedrazo-Tardajos, A.; Nuti, S.; Vande Velde, C.; De Wael, K.; Lenaerts, S.; Bals, S.; Verbruggen, S. |
Title |
Selectivity in ligand functionalization of photocatalytic metal oxide nanoparticles for phase transfer and self‐assembly applications |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Chemistry-A European Journal |
Abbreviated Journal |
Chem-Eur J |
Volume |
|
Issue |
|
Pages |
chem.202100029-15 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
Abstract |
Functionalization of photocatalytic metal oxide nanoparticles of TiO 2 , ZnO, WO 3 and CuO with amine‐terminated (oleylamine) and thiol‐terminated (1‐dodecanethiol) alkyl chained ligands was studied under ambient conditions. A high selectivity was observed in the binding specificity of a ligand towards nanoparticles of these different oxides. It was observed that oleylamine binds stably to only TiO 2 and WO 3 , while 1‐dodecanethiol binds stably only to ZnO and CuO. Similarly, polar to non‐polar solvent phase transfer of TiO 2 and WO 3 nanoparticles could be achieved by using oleylamine, but not by 1‐dodecanethiol, while the contrary holds for ZnO and CuO. The surface chemistry of ligand functionalized nanoparticles was probed by ATR‐FTIR spectroscopy, that enabled to elucidate the occupation of the ligands at the active sites. The photo‐stability of the ligands on the nanoparticle surface was determined by the photocatalytic self‐cleaning properties of the material. While TiO 2 and WO 3 degrade the ligands within 24 hours under both UV and visible light, ligands on ZnO and CuO remain unaffected. The gathered insights are also highly relevant from an application point of view. As an example, since the ligand functionalized nanoparticles are hydrophobic in nature, they can thus be self‐assembled at the air‐water interface, for obtaining nanoparticle films with demonstrated photocatalytic as well as anti‐fogging properties. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000652651400001 |
Publication Date |
2021-04-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0947-6539 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.317 |
Times cited |
15 |
Open Access |
OpenAccess |
Notes |
R.B. and S.W.V. acknowledge financial support from the University of Antwerp Special Research Fund (BOF) for a DOCPRO4 doctoral scholarship. S.B. and A.P.-T. acknowledge financial support from the European Commission under the Horizon 2020 Program by means of the grant agreement no. 731019 EUSMI and the ERC Consolidator grant no. 815128 REALNANO.; sygmaSB |
Approved |
Most recent IF: 5.317 |
Call Number |
UA @ admin @ c:irua:177495 |
Serial |
6787 |
Permanent link to this record |
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Author |
Khan, S.U.; Matshitse, R.; Borah, R.; Nemakal, M.; Moiseeva, E.O.; Dubinina, T.V.; Nyokong, T.; Verbruggen, S.W.; De Wael, K. |
Title |
Coupling of phthalocyanines with plasmonic gold nanoparticles by click chemistry for an enhanced singlet oxygen based photoelectrochemical sensing |
Type |
A1 Journal article |
Year |
2024 |
Publication |
ChemElectroChem |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
1-11 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
Coupling photosensitizers (PSs) with plasmonic nanoparticles increases the photocatalytic activity of PSs as the localized surface plasmon resonance (LSPR) of plasmonic nanoparticles leads to extreme concentration of light in their vicinity known as the near-field enhancement effect. To realize this in a colloidal phase, efficient conjugation of the PS molecules with the plasmonic nanoparticle surface is critical. In this work, we demonstrate the coupling of phthalocyanine (Pc) molecules with gold nanoparticles (AuNPs) in the colloidal phase via click chemistry. This conjugated Pc-AuNPs colloidal system is shown to enhance the photocatalytic singlet oxygen (1O2) production over non-conjugated Pcs and hence improve the photoelectrochemical detection of phenols. The plasmonic enhancement of the 1O2 generation by Pcs was clearly elucidated by complementary experimental and computational classical electromagnetic models. The dependence of plasmonic enhancement on the spectral position of the excitation laser wavelength and the absorbance of the Pc molecules with respect to the wavelength specific near-field enhancement is clearly demonstrated. A high similar to 8 times enhancement is obtained with green laser (532 nm) at the LSPR due to the maximum near-field enhancement at the resonance wavelength. Zinc phthalocyanine is covalently linked to plasmonic AuNPs via click chemistry to investigate the synergistic effect that boosts the overall activity toward the detection of HQ under visible light illumination. The 1O2 quantum yield of ZnPc improved significantly after conjugating with AuNPs, resulting in enhanced photoelectrochemical activity. image |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001214481000001 |
Publication Date |
2024-05-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-0216 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
4 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4; 2024 IF: 4.136 |
Call Number |
UA @ admin @ c:irua:205962 |
Serial |
9142 |
Permanent link to this record |
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Author |
Neven, L.; Barich, H.; Pelmuş, M.; Gorun, S.M.; De Wael, K. |
Title |
The role of singlet oxygen, superoxide, hydroxide, and hydrogen peroxide in the photoelectrochemical response of phenols at a supported highly fluorinated zinc phthalocyanine |
Type |
A1 Journal article |
Year |
2022 |
Publication |
ChemElectroChem |
Abbreviated Journal |
|
Volume |
9 |
Issue |
6 |
Pages |
e202200108-10 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Photoelectrochemical (PEC) sensing of phenolic compounds using singlet oxygen (1O2)-generating photocatalysts has emerged as a powerful detection tool. However, it is currently not known how experimental parameters, such as pH and applied potential, influence the generation of reactive oxygen species (ROS) and their photocurrents. In this article, the PEC response was studied over the 6 to 10 pH range using a rotating (ring) disk (R(R)DE) set-up in combination with quenchers, to identify the ROS formed upon illumination of a supported photosensitizer, F64PcZn. The photocurrents magnitude depended on the applied potential and the pH of the buffer solution. The anodic responses were caused by the oxidation of O2.−, generated due to the quenching of 1O2 with −OH and the reaction of 3O2 with [F64Pc(3-)Zn]. The cathodic responses were assigned to the reduction of 1O2 and O2.−, yielding H2O2. These insights may benefit 1O2 – based PEC sensing applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000773947300003 |
Publication Date |
2022-02-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-0216 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:187524 |
Serial |
8926 |
Permanent link to this record |
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Author |
Thiruvottriyur Shanmugam, S.; Van Echelpoel, R.; Boeye, G.; Eliaerts, J.; Samanipour, M.; Ching, H.Y.V.; Florea, A.; Van Doorslaer, S.; Van Durme, F.; Samyn, N.; Parrilla, M.; De Wael, K. |
Title |
Towards developing a screening strategy for ecstasy : revealing the electrochemical profile |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Chemelectrochem |
Abbreviated Journal |
Chemelectrochem |
Volume |
8 |
Issue |
24 |
Pages |
4826-4834 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
This article describes the development of an electrochemical screening strategy for 3,4-methylenedioxymethamphetamine (MDMA), the regular psychoactive compound in ecstasy (XTC) pills. We have investigated the specific electrochemical profile of MDMA and its electro-oxidation mechanisms at disposable graphite screen-printed electrodes. We have proved that the formation of a radical cation and subsequent reactions are indeed responsible for the electrode surface passivation, as evidenced by using electron paramagnetic resonance spectroscopy and electrochemistry. Thereafter, pure cutting agents and MDMA as well as simulated binary mixtures of compounds with MDMA were subjected to square wave voltammetry at pH 7 to understand the characteristic electrochemical profile. An additional measurement at pH 12 was able to resolve false positives and negatives occurring at pH 7. Finally, validation of the screening strategy was done by measuring a set of ecstasy street samples. Overall, our proposed electrochemical screening strategy has been demonstrated for the rapid, sensitive, and selective detection of MDMA, resolving most of the false positives and negatives given by the traditional Marquis color tests, thus exhibiting remarkable promises for the on-site screening of MDMA. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000735883700020 |
Publication Date |
2021-12-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-0216 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.136 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 4.136 |
Call Number |
UA @ admin @ c:irua:184371 |
Serial |
8680 |
Permanent link to this record |
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Author |
Trashin, S.; De Jong, M.; Meynen, V.; Dewilde, S.; De Wael, K. |
Title |
Attaching redox proteins onto electrode surfaces by bis-silane |
Type |
A1 Journal article |
Year |
2016 |
Publication |
ChemElectroChem |
Abbreviated Journal |
Chemelectrochem |
Volume |
3 |
Issue |
7 |
Pages |
1035-1038 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Immobilization of redox proteins on electrode surfaces is of special interest for mechanistic studies and applications because of a well-controlled redox state of protein molecules by a polarized electrode and fast electron transfer kinetics, free from diffusion limitation. Here, bis-organosilane (1,2-bis(trimethoxysilyl)ethane) was applied as a fresh solution in a pH 7 phosphate buffer without use of any organic solvent, sol-gel or mesoporous bulk matrix. A short aging period of 30 minutes before deposition on the electrodes was optimal for the immobilization of proteins. Three redox proteins (cytochrome c, neuroglobin and GLB-12) were confined to the gold surface of electrodes with high coverages and stability, indicating that the suggested technique is simple, efficient and generic in nature. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000380043500001 |
Publication Date |
2016-03-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-0216 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.136 |
Times cited |
4 |
Open Access |
|
Notes |
; The authors thank the Fund for Scientific Research-Flanders (FWO) (Grant G.0687.13) and the GOA-BOF UA 2013-2016 (project ID 28312) for funding. ; |
Approved |
Most recent IF: 4.136 |
Call Number |
UA @ admin @ c:irua:132628 |
Serial |
5485 |
Permanent link to this record |
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Author |
de Jong, M.; Sleegers, N.; Schram, J.; Daems, D.; Florea, A.; De Wael, K. |
Title |
A Benzocaine‐Induced Local Near‐Surface pH Effect: Influence on the Accuracy of Voltammetric Cocaine Detection |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Analysis & Sensing |
Abbreviated Journal |
Anal. Sens. |
Volume |
|
Issue |
|
Pages |
anse.202000012 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
This work reports on a local induced near-surface pH effect (pHS), due to the presence of one analyte, leading to an influence or even suppression of redox signals of a second analyte present in solution. This concept and its impact on voltammetric sensing is illustrated by focusing on the detection of cocaine in the presence of the common adulterant benzocaine. An in-depth study on the occurring interference mechanism and why it occurs for benzocaine specifically and not for other adulterants was performed through the use of multiple electrochemical strategies. It was concluded that the potential shift and loss of intensity of the squarewave voltammetric cocaine signal in the presence of benzocaine was caused by a local pHS effect. A cathodic pretreatment strategy was developed to nonetheless allow accurate cocaine detection. The gathered insights are useful to explain unidentified phenomena involving compounds with properties similar to benzocaine in voltammetric electroanalysis. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2020-10-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2629-2742 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
The authors acknowledge financial support from IOF-SBO/POC (UAntwerp), the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N and Grant 1SB 8120N, and VLAIO IM [HBC.2019.2181]. |
Approved |
Most recent IF: NA |
Call Number |
AXES @ axes @c:irua:173031 |
Serial |
6427 |
Permanent link to this record |
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Author |
Beltran, V.; Marchetti, A.; Nuyts, G.; Leeuwestein, M.; Sandt, C.; Borondics, F.; De Wael, K. |
Title |
Nanoscale analysis of historical paintings by means of O‐PTIR spectroscopy : the identification of the organic particles in L’Arlésienne (portrait of Madame Ginoux) by Van Gogh |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Angewandte Chemie-International Edition |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
60 |
Issue |
42 |
Pages |
22753-22760 |
Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Optical-photothermal infrared (O-PTIR) spectroscopy is a recently developed technique that provides spectra comparable to traditional transmission FTIR spectroscopy with nanometric spatial resolution. Hence, O-PTIR is a promising candidate for the analysis of historical paintings, as well as other cultural heritage objects, but its potential has not yet been evaluated. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000694015700001 |
Publication Date |
2021-06-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 11.994 |
Call Number |
UA @ admin @ c:irua:179989 |
Serial |
8291 |
Permanent link to this record |
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Author |
Lybaert, J.; Trashin, S.; Maes, B.U.W.; De Wael, K.; Abbaspour Tehrani, K. |
Title |
Cooperative electrocatalytic and chemoselective alcohol oxidation by Shvo's catalyst |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Advanced synthesis and catalysis |
Abbreviated Journal |
Adv Synth Catal |
Volume |
359 |
Issue |
6 |
Pages |
919-925 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY) |
Abstract |
A new electrocatalytic conversion of alcohols to ketones and aldehydes was developed based on an electrochemical study of Shvos complex. The oxidation of secondary alcohols was efficiently performed under mild conditions using a catalytic amount of Shvos catalyst, in combination with a sub-stoichiometric amount of 2,6-dimethoxy-1,4- benzoquinone in N,N-dimethylformamide at 80 8C. The hydroquinone thus formed is continuously reoxidized with the aid of an electrochemical device. Excellent yields for different ketones, aromatic as well as aliphatic and a,b-unsaturated ketones, are obtained. In addition, chemoselectivity towards oxidation of the secondary alcohol is achieved when converting vicinal diols such as 1,2-octanediol and 1,2-decanediol. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000397584000003 |
Publication Date |
2017-01-26 |
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 |
|
ISSN |
1615-4150; 1615-4169 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.646 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was financially supported by the University of Antwerp (BOF), the Research Foundation – Flanders (FWO) and the Hercules Foundation. ; |
Approved |
Most recent IF: 5.646 |
Call Number |
UA @ admin @ c:irua:139795 |
Serial |
5559 |
Permanent link to this record |
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Author |
Parrilla, M.; De Wael, K. |
Title |
Wearable self‐powered electrochemical devices for continuous health management |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
31 |
Issue |
50 |
Pages |
2107042 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
The wearable revolution is already present in society through numerous gadgets. However, the contest remains in fully deployable wearable (bio)chemical sensing. Its use is constrained by the energy consumption which is provided by miniaturized batteries, limiting the autonomy of the device. Hence, the combination of materials and engineering efforts to develop sustainable energy management is paramount in the next generation of wearable self-powered electrochemical devices (WeSPEDs). In this direction, this review highlights for the first time the incorporation of innovative energy harvesting technologies with top-notch wearable self-powered sensors and low-powered electrochemical sensors toward battery-free and self-sustainable devices for health and wellbeing management. First, current elements such as wearable designs, electrochemical sensors, energy harvesters and storage, and user interfaces that conform WeSPEDs are depicted. Importantly, the bottlenecks in the development of WeSPEDs from an analytical perspective, product side, and power needs are carefully addressed. Subsequently, energy harvesting opportunities to power wearable electrochemical sensors are discussed. Finally, key findings that will enable the next generation of wearable devices are proposed. Overall, this review aims to bring new strategies for an energy-balanced deployment of WeSPEDs for successful monitoring of (bio)chemical parameters of the body toward personalized, predictive, and importantly, preventive healthcare. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000694642500001 |
Publication Date |
2021-09-09 |
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 |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:181306 |
Serial |
8750 |
Permanent link to this record |
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Author |
Teymourian, H.; Parrilla, M.; Sempionatto, J.R.; Montiel, N.F.; Barfidokht, A.; Van Echelpoel, R.; De Wael, K.; Wang, J. |
Title |
Wearable Electrochemical Sensors for the Monitoring and Screening of Drugs |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Sensors |
Abbreviated Journal |
Acs Sensors |
Volume |
5 |
Issue |
9 |
Pages |
2679-2700 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Wearable electrochemical sensors capable of noninvasive monitoring of chemical markers represent a rapidly emerging digital-health technology. Recent advances toward wearable continuous glucose monitoring (CGM) systems have ignited tremendous interest in expanding such sensor technology to other important fields. This article reviews for the first time wearable electrochemical sensors for monitoring therapeutic drugs and drugs of abuse. This rapidly emerging class of drug-sensing wearable devices addresses the growing demand for personalized medicine, toward improved therapeutic outcomes while minimizing the side effects of drugs and the related medical expenses. Continuous, noninvasive monitoring of therapeutic drugs within bodily fluids empowers clinicians and patients to correlate the pharmacokinetic properties with optimal outcomes by realizing patient-specific dose regulation and tracking dynamic changes in pharmacokinetics behavior while assuring the medication adherence of patients. Furthermore, wearable electrochemical drug monitoring devices can also serve as powerful screening tools in the hands of law enforcement agents to combat drug trafficking and support on-site forensic investigations. The review covers various wearable form factors developed for noninvasive monitoring of therapeutic drugs in different body fluids and toward on-site screening of drugs of abuse. The future prospects of such wearable drug monitoring devices are presented with the ultimate goals of introducing accurate real-time drug monitoring protocols and autonomous closed-loop platforms toward precise dose regulation and optimal therapeutic outcomes. Finally, current unmet challenges and existing gaps are discussed for motivating future technological innovations regarding personalized therapy. The current pace of developments and the tremendous market opportunities for such wearable drug monitoring platforms are expected to drive intense future research and
commercialization efforts. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000573560800003 |
Publication Date |
2020-09-25 |
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 |
|
ISSN |
2379-3694 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.9 |
Times cited |
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Open Access |
|
Notes |
Horizon 2020 Framework Programme, 833787 ; Center of Wearable Sensors, University of California San Diego; |
Approved |
Most recent IF: 8.9; 2020 IF: NA |
Call Number |
AXES @ axes @c:irua:170894 |
Serial |
6436 |
Permanent link to this record |
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Author |
Schram, J.; Parrilla, M.; Sleegers, N.; Samyn, N.; Bijvoets, S.M.; Heerschop, M.W.J.; van Nuijs, A.L.N.; De Wael, K. |
Title |
Identifying Electrochemical Fingerprints of Ketamine with Voltammetry and Liquid Chromatography–Mass Spectrometry for Its Detection in Seized Samples |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
92 |
Issue |
19 |
Pages |
13485-13492 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
Herein, a straightforward electrochemical approach for the determination of ketamine in street samples and seizures is presented by employing screen-printed electrodes (SPE). Square wave voltammetry (SWV) is used to study the electrochemical behavior of the illicit drug, thus profiling the different oxidation states of the substance at different pHs. Besides, the oxidation pathway of ketamine on SPE is investigated for the first time with liquid chromatography–high-resolution mass spectrometry. Under the optimized conditions, the calibration curve of ketamine at buffer solution (pH 12) exhibits a sensitivity of 8.2 μA μM–1, a linear relationship between 50 and 2500 μM with excellent reproducibility (RSD = 2.2%, at 500 μM, n = 7), and a limit of detection (LOD) of 11.7 μM. Subsequently, binary mixtures of ketamine with adulterants and illicit drugs are analyzed with SWV to investigate the electrochemical fingerprint. Moreover, the profile overlapping between different substances is addressed by the introduction of an electrode pretreatment and the integration of a tailor-made script for data treatment. Finally, the approach is tested on street samples from forensic seizures. Overall, this system allows for the on-site identification of ketamine by law enforcement agents in an easy-to-use and rapid manner on cargos and seizures, thereby disrupting the distribution channel and avoiding the illicit drug reaching the end-user. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000580426800091 |
Publication Date |
2020-10-06 |
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 |
|
ISSN |
0003-2700 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
Notes |
Universiteit Antwerpen; H2020 Societal Challenges, 833787 ; Fonds Wetenschappelijk Onderzoek, 1S3765817N 1SB8120N ; |
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
Call Number |
AXES @ axes @c:irua:170523 |
Serial |
6435 |
Permanent link to this record |
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Author |
Rather, J.A.; Pilehvar, S.; De Wael, K. |
Title |
Polycyclodextrin and carbon nanotubes as composite for tyrosinase immobilization and its superior electrocatalytic activity towards butylparaben an endocrine disruptor |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of nanoscience and nanotechnology |
Abbreviated Journal |
|
Volume |
15 |
Issue |
5 |
Pages |
3365-3372 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
We developed a protocol for the immobilization of tyrosinase (Tyr) on the composite of polycyclodextrin polymer (CDP) and carbon nanotubes for the detection of an endocrine disruptor, i.e., butylparaben (BP). The formation of the CDP polymer was characterized by UV-Vis spectrophotometry. The conducting film of cross-linked CDP and carbon nanotubes, displays excellent matrix capabilities for Tyr immobilization. The host-guest chemical reaction ability of CD and the ππ stacking interaction assure the bioactivity of Tyr towards butylparaben. The developed biosensor was characterized electrochemically by electrochemical impedance spectroscopy. The enzyme-substrate kinetic parameters such as the apparent Michaelis-Menten constant (K M app) was measured under saturated substrate concentration. The determination of butylparaben was carried out by using square wave voltammetry over the concentration range of 2.1 to 35.4 μM with a detection limit of 0.1 μM. The fabricated biosensor was successfully applied in real-life cosmetic samples with good recovery ranging from 98.5 to 102.8%. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000347435200007 |
Publication Date |
2014-10-01 |
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 |
1533-4899 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
3 |
Open Access |
|
Notes |
; The authors are highly thankful for the mobility grant (Non-Europe Postdoc Fellowship) for one of the author (Jahangir Ahmad Rather) supported by the Belgian Federal Science Policy (Belspo) co-funded by the Marie Curie Actions from the European Commission. Sanaz Pilehvar is funded by BOF-DOCPRO UA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:119550 |
Serial |
5776 |
Permanent link to this record |
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Author |
Eliaerts, J.; Meert, N.; Dardenne, P.; Baeten, V.; Pierna, J.-A.F.; Van Durme, F.; De Wael, K.; Samyn, N. |
Title |
Comparison of spectroscopic techniques combined with chemometrics for cocaine powder analysis |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Analytical Toxicology |
Abbreviated Journal |
J Anal Toxicol |
Volume |
44 |
Issue |
8 |
Pages |
851-860 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Spectroscopic techniques combined with chemometrics are a promising tool for analysis of seized drug powders. In this study, the performance of three spectroscopic techniques [Mid-InfraRed (MIR), Raman and Near-InfraRed (NIR)] was compared. In total, 364 seized powders were analyzed and consisted of 276 cocaine powders (with concentrations ranging from 4 to 99 w%) and 88 powders without cocaine. A classification model (using Support Vector Machines [SVM] discriminant analysis) and a quantification model (using SVM regression) were constructed with each spectral dataset in order to discriminate cocaine powders from other powders and quantify cocaine in powders classified as cocaine positive. The performances of the models were compared with gas chromatography coupled with mass spectrometry (GC-MS) and gas chromatography with flame-ionization detection (GC-FID). Different evaluation criteria were used: number of false negatives (FNs), number of false positives (FPs), accuracy, root mean square error of cross-validation (RMSECV) and determination coefficients (R-2). Ten colored powders were excluded from the classification data set due to fluorescence background observed in Raman spectra. For the classification, the best accuracy (99.7%) was obtained with MIR spectra. With Raman and NIR spectra, the accuracy was 99.5% and 98.9%, respectively. For the quantification, the best results were obtained with NIR spectra. The cocaine content was determined with a RMSECV of 3.79% and a R-2 of 0.97. The performance of MIR and Raman to predict cocaine concentrations was lower than NIR, with RMSECV of 6.76% and 6.79%, respectively and both with a R-2 of 0.90. The three spectroscopic techniques can be applied for both classification and quantification of cocaine, but some differences in performance were detected. The best classification was obtained with MIR spectra. For quantification, however, the RMSECV of MIR and Raman was twice as high in comparison with NIR. Spectroscopic techniques combined with chemometrics can reduce the workload for confirmation analysis (e.g., chromatography based) and therefore save time and resources. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000606735000011 |
Publication Date |
2020-08-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0146-4760; 1945-2403 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.5 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.5; 2020 IF: 2.409 |
Call Number |
UA @ admin @ c:irua:175117 |
Serial |
7697 |
Permanent link to this record |