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Author Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M.
Title Capillary Condensation of Water in Graphene Nanocapillaries Type A1 Journal Article
Year 2024 Publication Nano Letters Abbreviated Journal Nano Lett.
Volume 24 Issue 18 Pages 5625-5630
Keywords (down) A1 Journal Article; CMT
Abstract Recent experiments have revealed that the macroscopic Kelvin equation remains surprisingly accurate even for nanoscale capillaries. This phenomenon was so far explained by the oscillatory behavior of the solid−liquid interfacial free energy. We here demonstrate thermodynamic and capillarity inconsistencies with this explanation. After revising the Kelvin equation, we ascribe its validity at nanoscale confinement to the effect of disjoining pressure.

To substantiate our hypothesis, we employed molecular dynamics simulations to evaluate interfacial heat transfer and wetting properties. Our assessments unveil a breakdown in a previously established proportionality between the work of adhesion and the Kapitza conductance at capillary heights below 1.3 nm, where the dominance of the work of adhesion shifts primarily from energy to entropy. Alternatively, the peak density of the initial water layer can effectively probe the work of adhesion. Unlike under bulk conditions, high confinement renders the work of adhesion entropically unfavorable.
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Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links
Impact Factor 10.8 Times cited Open Access
Notes This work was supported by Research Foundation-Flanders (FWO, project No. G099219N). The computational resources used in this work were provided by the HPC core facility CalcUA of the University of Antwerp, and the Flemish Supercomputer Center (VSC), funded by FWO and the Flemish Government. Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ lucian @ Serial 9123
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Author Meng, S.; Wu, L.; Liu, M.; Cui, Z.; Chen, Q.; Li, S.; Yan, J.; Wang, L.; Wang, X.; Qian, J.; Guo, H.; Niu, J.; Bogaerts, A.; Yi, Y.
Title Plasma‐driven<scp>CO2</scp>hydrogenation to<scp>CH3OH</scp>over<scp>Fe2O3</scp>/<scp>γ‐Al2O3</scp>catalyst Type A1 Journal Article
Year 2023 Publication AIChE Journal Abbreviated Journal AIChE Journal
Volume 69 Issue 10 Pages e18154
Keywords (down) A1 Journal Article; chemisorbed oxygen, CO2 hydrogenation, iron-based catalyst, methanol production, plasma catalysis; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract We report a plasma‐assisted CO<sub>2</sub>hydrogenation to CH<sub>3</sub>OH over Fe<sub>2</sub>O<sub>3</sub>/γ‐Al<sub>2</sub>O<sub>3</sub>catalysts, achieving 12% CO<sub>2</sub>conversion and 58% CH<sub>3</sub>OH selectivity at a temperature of nearly 80°C atm pressure. We investigated the effect of various supports and loadings of the Fe‐based catalysts, as well as optimized reaction conditions. We characterized catalysts by X‐ray powder diffraction (XRD), hydrogen temperature programmed reduction (H<sub>2</sub>‐TPR), CO<sub>2</sub>and CO temperature programmed desorption (CO<sub>2</sub>/CO‐TPD), high‐resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), x‐ray photoelectron spectroscopy (XPS), Mössbauer, and Fourier transform infrared<bold>(</bold>FTIR). The XPS results show that the enhanced CO<sub>2</sub>conversion and CH<sub>3</sub>OH selectivity are attributed to the chemisorbed oxygen species on Fe<sub>2</sub>O<sub>3</sub>/γ‐Al<sub>2</sub>O<sub>3</sub>. Furthermore, the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) and TPD results illustrate that the catalysts with stronger CO<sub>2</sub>adsorption capacity exhibit a higher reaction performance.<italic>In situ</italic>DRIFTS gain insight into the specific reaction pathways in the CO<sub>2</sub>/H<sub>2</sub>plasma. This study reveals the role of chemisorbed oxygen species as a key intermediate, and inspires to design highly efficient catalysts and expand the catalytic systems for CO<sub>2</sub>hydrogenation to CH<sub>3</sub>OH.
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Publisher Place of Publication Editor
Language Wos 001022420000001 Publication Date 2023-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-1541 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited Open Access Not_Open_Access
Notes Fundamental Research Funds for the Central Universities, DUT18JC42 ; National Natural Science Foundation of China, 21908016 21978032 ; Approved Most recent IF: 3.7; 2023 IF: 2.836
Call Number PLASMANT @ plasmant @c:irua:197829 Serial 8959
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Author Le Compte, M.; Cardenas De La Hoz, E.; Peeters, S.; Rodrigues Fortes, F.; Hermans, C.; Domen, A.; Smits, E.; Lardon, F.; Vandamme, T.; Lin, A.; Vanlanduit, S.; Roeyen, G.; van Laere, S.; Prenen, H.; Peeters, M.; Deben, C.
Title Single-organoid analysis reveals clinically relevant treatment-resistant and invasive subclones in pancreatic cancer Type A1 Journal article
Year 2023 Publication npj Precision Oncology Abbreviated Journal
Volume 7 Issue 1 Pages 128-14
Keywords (down) A1 Journal article; Center for Oncological Research (CORE); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC)
Abstract Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases, characterized by a treatment-resistant and invasive nature. In line with these inherent aggressive characteristics, only a subset of patients shows a clinical response to the standard of care therapies, thereby highlighting the need for a more personalized treatment approach. In this study, we comprehensively unraveled the intra-patient response heterogeneity and intrinsic aggressive nature of PDAC on bulk and single-organoid resolution. We leveraged a fully characterized PDAC organoid panel ( N  = 8) and matched our artificial intelligence-driven, live-cell organoid image analysis with retrospective clinical patient response. In line with the clinical outcomes, we identified patient-specific sensitivities to the standard of care therapies (gemcitabine-paclitaxel and FOLFIRINOX) using a growth rate-based and normalized drug response metric. Moreover, the single-organoid analysis was able to detect resistant as well as invasive PDAC organoid clones, which was orchestrates on a patient, therapy, drug, concentration and time-specific level. Furthermore, our in vitro organoid analysis indicated a correlation with the matched patient progression-free survival (PFS) compared to the current, conventional drug response readouts. This work not only provides valuable insights on the response complexity in PDAC, but it also highlights the potential applications (extendable to other tumor types) and clinical translatability of our approach in drug discovery and the emerging era of personalized medicine.
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Publisher Place of Publication Editor
Language Wos 001118015800001 Publication Date 2023-12-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-768x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:201455 Serial 9091
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Author Verbruggen, L.; Verheggen, L.; Vanhoutte, G.; Loly, C.; Lybaert, W.; Borbath, I.; Vergauwe, P.; Hendrickx, K.; Debeuckelaere, C.; de Haar-Holleman, A.; Van Laethem, J.-L.; Peeters, M.
Title A real-world analysis on the efficacy and tolerability of liposomal irinotecan plus 5-fluorouracil and folinic acid in metastatic pancreatic ductal adenocarcinoma in Belgium Type A1 Journal article
Year 2023 Publication Therapeutic advances in medical oncology Abbreviated Journal
Volume 15 Issue Pages 1-13
Keywords (down) A1 Journal article; Center for Oncological Research (CORE)
Abstract Background: Currently, nanoliposomal irinotecan (nal-IRI) + 5-fluorouracil/folinic acid (5-FU/ LV) is the only approved second-line treatment for patients suffering from metastatic pancreatic ductal adenocarcinoma (mPDAC). However, also other chemotherapeutic regimens are used in this setting and due to the lack of clear real-world data on the efficacy of the different regimens, there is no consensus on the optimal treatment sequence for mPDAC patients. Objectives: To provide information on the safe and efficacious use of nal-IRI + 5-FU/LV in clinical practice in Belgium, which is needed for healthcare professionals to estimate the risk-benefit ratio of the intervention. Methods: Medical data of adult patients with mPDAC who were treated with nal-IRI + 5-FU/ LV in one of the participating Belgian hospitals were retrospectively collected. Kaplan-Meier analysis was performed to obtain survival curves to estimate the median overall survival (OS) and progression-free survival (PFS). All other results were presented descriptively. Results: A total of 56 patients [median age at diagnosis: 69 years (range 43 years), 57.1% male] were included. Patients received a median of 5 (range 49 cycles) nal-IRI + 5-FU/LV cycles, extended over 10 weeks (range 130.8 weeks). The median start dose for nal-IRI was 70 mg/ m(2) (range 49.24 mg/m(2)) and chemotherapy dose reduction and delay occurred in, respectively, 42.8% and 37.5% of the patients. The median OS was 6.8 months (95% CI: 5.6-8.4 months) with a 6-month survival rate of 57.4% and a 1-year survival rate of 27.8% in the overall study population. The median OS for patients treated with nal-IRI as second-line therapy or as laterline treatment was, respectively, 6.8 months (95% CI: 5.9-7.0 months) and 5.6 months (95% CI: 4.2-no upper limit). In the overall study population, a median PFS of 3.1 months (95% CI: 2.4-4.6 months) and a disease control rate of 48.3%, comprising 30.4% stable disease, 16.1% partial and 1.8% complete response, was observed. The median PFS for patients treated with nal-IRI as second-line therapy was 3.9 months (95% CI: 2.8-4.8 months) while this was 2.4 months (95% CI: 1.9-9.1 months) for those that received nal-IRI in a later-line treatment. In terms of safety, gastrointestinal problems occurred most (64.3% of the patients) and from all reported treatment emergent adverse events, 39.2% were grade 3 or 4. Conclusion: Nal-IRI + 5-FU/LV is a valuable, effective, and safe sequential treatment option following gemcitabine-based therapy in patients with mPDAC.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001051446400001 Publication Date 2023-08-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1758-8340; 1758-8359 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.9 Times cited Open Access
Notes Approved Most recent IF: 4.9; 2023 IF: 6.294
Call Number UA @ admin @ c:irua:199296 Serial 9183
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Author Van Holsbeke, C.S.; Verhulst, S.L.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Verdonck, P.R.; van Doorn, J.W.D.; Nadjmi, N.; de Backer, W.A.
Title Change in upper airway geometry between upright and supine position during tidal nasal breathing Type A1 Journal article
Year 2014 Publication Journal Of Aerosol Medicine And Pulmonary Drug Delivery Abbreviated Journal J Aerosol Med Pulm D
Volume 27 Issue 1 Pages 51-57
Keywords (down) A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)
Abstract
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Publisher Place of Publication Editor
Language Wos 000331144500007 Publication Date 2013-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1941-2711;1941-2703; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.528 Times cited 16 Open Access
Notes ; ; Approved Most recent IF: 2.528; 2014 IF: 2.798
Call Number UA @ lucian @ c:irua:115759 Serial 308
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Author Vos, W.; de Backer, J.; Poli, G.; De Volder, A.; Ghys, L.; Van Holsbeke, C.; Vinchurkar, S.; De Backer, L.; de Backer, W.
Title Novel functional imaging of changes in small airways of patients treated with extrafine beclomethasone/formoterol Type A1 Journal article
Year 2013 Publication Respiration Abbreviated Journal Respiration
Volume 86 Issue 5 Pages 393-401
Keywords (down) A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Background: Inhaled formulations using extrafine particles of long-acting beta(2)-agonists and corticosteroids were developed to optimize asthma treatment. Findings that these combinations reach and treat smaller airways more effectively are predominantly based on general non-specific outcomes with little information on regional characteristics. Objectives: This study aims to assess long-term effects of extrafine beclomethasone/formoterol on small airways of asthmatic patients using novel functional imaging methods. Methods: Twenty-four stable asthma patients were subdivided into three groups (steroid naive, n = 7; partially controlled, n = 6; well controlled, n = 11). Current treatment was switched to a fixed combination of extrafine beclomethasone/formoterol (Foster (R); Chiesi Pharmaceuticals, Parma, Italy). Patients underwent lung function evaluation and thorax high-resolution computerized tomography (HRCT) scan. Local airway resistance was obtained from computational fluid dynamics (CFD). Results: After 6 months, the entire population showed improvement in pre-bronchodilation imaging parameters, including small airway volume (p = 0.0007), resistance (p = 0.011), and asthma control score (p = 0.016). Changes in small airway volume correlated with changes in asthma control score (p = 0.004). Forced expiratory volume in 1 s (p = 0.044) and exhaled nitric oxide (p = 0.040) also improved. Functional imaging provided more detail and clinical relevance compared to lung function tests, especially in the well-controlled group where only functional imaging parameters showed significant improvement, while the correlation with asthma control score remained. Conclusions: Extrafine beclomethasone/formoterol results in a significant reduction of small airway obstruction, detectable by functional imaging (HRCT/CFD). Changes in imaging parameters correlated significantly with clinically relevant improvements. This indicates that functional imaging is a useful tool for sensitive assessment of changes in the respiratory system after asthma treatment. Copyright (C) 2013 S. Karger AG, Basel
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Corporate Author Thesis
Publisher Place of Publication Basel Editor
Language Wos 000329046200006 Publication Date 2013-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1423-0356;0025-7931; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.772 Times cited 30 Open Access
Notes ; ; Approved Most recent IF: 2.772; 2013 IF: 2.924
Call Number UA @ lucian @ c:irua:113762 Serial 2376
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Author De Backer, L.A.; Vos, W.; de Backer, J.; Van Holsbeke, C.; Vinchurkar, S.; de Backer, W.
Title The acute effect of budesonide/formoterol in COPD : a multi-slice computed tomography and lung function study Type A1 Journal article
Year 2012 Publication European Respiratory Journal Abbreviated Journal Eur Respir J
Volume 40 Issue 2 Pages 298-305
Keywords (down) A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract The Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification of chronic obstructive pulmonary disease (COPD) does not always match with other clinical disease descriptors such as exacerbation frequency and quality of life, indicating that forced expiratory volume in 1 s (FEV1) is not a perfect descriptor of the disease. The aim of this study was to find out whether changes in airway geometry after inhalation of the most commonly used inhalation therapy in severe COPD can more adequately be described with an image-based approach than with spirometry. 10 COPD GOLD stage III patients were assessed in a double-blind crossover study. Airway volumes were analysed using segmentation of multi-slice computed tomography (MSCT) images; airway resistance was determined using computational fluid dynamics (CFD). Distal airway volume significantly increased (p=0.011) in patients 4 h after receiving a budesonide/formoterol combination from 9.6+/-4.67 cm(3) to 10.14+/-4.81 cm(3). Also CFD-determined airway resistance significantly decreased (p=0.047) from 0.051+/-0.021 kPa.s.L-1 to 0.043+/- 0.019 kPa.s.L-1. None of the lung function parameters showed a significant change. Only functional residual capacity (FRC) showed a trend to decline (p=0.056). Only the image-based parameters were able to predict the visit at which the combination product was administered. This study showed that imaging is a sensitive, complementary tool to describe changes in airway structure.
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Corporate Author Thesis
Publisher Place of Publication Copenhagen Editor
Language Wos 000307291700006 Publication Date 2011-12-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0903-1936;1399-3003; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.569 Times cited 37 Open Access
Notes ; ; Approved Most recent IF: 10.569; 2012 IF: 6.355
Call Number UA @ lucian @ c:irua:101113 Serial 3568
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Author de Backer, J.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Parizel, P.M.; de Backer, W.
Title Effect of high-dose N-acetylcysteine on airway geometry, inflammation, and oxidative stress in COPD patients Type A1 Journal article
Year 2013 Publication International Journal Of Chronic Obstructive Pulmonary Disease Abbreviated Journal Int J Chronic Obstr
Volume 8 Issue Pages 569-579
Keywords (down) A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Background: Previous studies have demonstrated the potential beneficial effect of N-acetylcysteine (NAC) in chronic obstructive pulmonary disease (COPD). However, the required dose and responder phenotype remain unclear. The current study investigated the effect of high-dose NAC on airway geometry, inflammation, and oxidative stress in COPD patients. Novel functional respiratory imaging methods combining multislice computed tomography images and computer-based flow simulations were used with high sensitivity for detecting changes induced by the therapy. Methods: Twelve patients with Global Initiative for Chronic Obstructive Lung Disease stage II COPD were randomized to receive NAC 1800 mg or placebo daily for 3 months and were then crossed over to the alternative treatment for a further 3 months. Results: Significant correlations were found between image-based resistance values and glutathione levels after treatment with NAC (P = 0.011) and glutathione peroxidase at baseline (P = 0.036). Image-based resistance values appeared to be a good predictor for glutathione peroxidase levels after NAC (P = 0.02), changes in glutathione peroxidase levels (P = 0.035), and reduction in lobar functional residual capacity levels (P = 0.00084). In the limited set of responders to NAC therapy, the changes in airway resistance were in the same order as changes induced by budesonide/formoterol. Conclusion: A combination of glutathione, glutathione peroxidase, and imaging parameters could potentially be used to phenotype COPD patients who would benefit from addition of NAC to their current therapy. The findings of this small pilot study need to be confirmed in a larger pivotal trial.
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Publisher Place of Publication Editor
Language Wos 000327537300001 Publication Date 2013-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1178-2005; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.157 Times cited 21 Open Access
Notes ; JDB is a founder/shareholder of FluidDA NV, Kontich, Belgium. WV, SV, and CVH are employed by FluidDA NV, and WDB is the director of FluidDA NV. PMP and RC have no conflicts of interest to report. The study was supported by Zambon SpA, Bresso, Italy. ; Approved Most recent IF: 3.157; 2013 IF: NA
Call Number UA @ lucian @ c:irua:112799 Serial 813
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Author van Dyck, K.; Robberecht, H.; van Cauwenbergh, R.; Deelstra, H.; Arnaud, J.; Willemyns, L.; Benijts, F.; Centeno, J.A.; Taylor, H.; Soares, M.E.; Bastos, M.L.; Ferreira, M.A.; d'Haese, P.C.; Lamberts, L.V.; Hoenig, M.; Knapp, G.; Lugowski, S.J.; Moens, L.; Riondato, J.; Van Grieken, R.; Claes, M.; Verheyen, R.; Clement, L.; Uytterhoeven, M.
Title Spectrometric determination of silicon in food and biological samples: an interlaboratory trial Type A1 Journal article
Year 2000 Publication Journal of analytical atomic spectrometry Abbreviated Journal
Volume 15 Issue 6 Pages 735-741
Keywords (down) A1 Journal article; Behavioural Ecology & Ecophysiology; Pathophysiology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Accuracy and precision of silicon determination in biological matrices (serum, urine, water, beer and spinach) by spectrometric techniques (when necessary after acid destruction) were assessed by means of a collaborative interlaboratory trial. The trial was set up in accordance with ISO 5725-2 (1994). The relative overall repeatability standard deviation was acceptable. It varied between 4% for spinach powder (mean content: 176 mg kg(-1)) and 11% for serum (mean content: 5.33 mg L-1). On the other hand, the relative overall between-laboratory standard deviation was found to vary from a satisfactorily 15% for spinach after destruction (mean content: 3.32 mg L-1) to an unacceptable 107% for spinach powder (mean content: 176 mg kg(-1)). The overall conclusion of the trial was that silicon determination in biological matrices can properly be performed by spectrometric techniques. However, when sample pretreatment (i.e., acid destruction) is needed prior to silicon determination problems still remain.
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Publisher Place of Publication Editor
Language Wos 000087419300025 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:27841 Serial 8574
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Author De Jong, M.; Sleegers, N.; Florea, A.; Van Loon, J.; van Nuijs, A.L.N.; Samyn, N.; De Wael, K.
Title Unraveling the mechanisms behind the complete suppression of cocaine electrochemical signals by chlorpromazine, promethazine, procaine, and dextromethorphan Type A1 Journal article
Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 91 Issue 24 Pages 15453-15460
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre; Product development
Abstract The present work investigates the challenges accompanied by the electrochemical cocaine detection in physiological conditions (pH 7) in the presence of chlorpromazine, promethazine, procaine, and dextromethorphan, frequently used cutting agents in cocaine street samples. The problem translates into the absence of the cocaine oxidation signal (signal suppression) when in a mixture with one of these compounds, leading to false negative results. Although a solution to this problem was provided through earlier experiments of our group, the mechanisms behind the suppression are now fundamentally investigated via electrochemical and liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) strategies. The latter was used to confirm the passivation of the electrodes due to their interaction with promethazine and chlorpromazine. Electron transfer mechanisms were further identified via linear sweep voltammetry. Next, adsorption experiments were performed on the graphite screen printed electrodes both with and without potential assistance in order to confirm if the suppression of the cocaine signals is due to passivation induced by the cutting agents or their oxidized products. The proposed strategies allowed us to identify the mechanisms of cocaine suppression for each cutting agent mentioned. Suppression due to procaine and dextromethorphan is caused by fouling of the electrode surface by their oxidized forms, while for chlorpromazine and promethazine the suppression of the cocaine signal is related to the strong adsorption of these (nonoxidized) cutting agents onto the graphite electrode surface. These findings provide fundamental insights in possible suppression and other interfering mechanisms using electrochemistry in general not only in the drug detection sector.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000503910600018 Publication Date 2019-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited Open Access
Notes ; The authors acknowledge financial support from IOF-SBO/POC (UAntwerp) and the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:165727 Serial 5887
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Author Bottari, F.; Moro, G.; Sleegers, N.; Florea, A.; Cowen, T.; Piletsky, S.; van Nuijs, A.L.N.; De Wael, K.
Title Electropolymerized o-phenylenediamine on graphite promoting the electrochemical detection of nafcillin Type A1 Journal article
Year 2019 Publication Electroanalysis Abbreviated Journal Electroanal
Volume 32 Issue 32 Pages 135-141
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract By combining molecular modelling and electrochemistry we envision the creation of modified electrodes tailored for a more sensitive and selective detection of a single analyte. In this study we report on a graphite screen printed electrode modified with electropolymerized o-phenylenediamine, selected by rational design, which promotes the detection of nafcillin (NAF), an antibiotic. Parameters such as monomer concentration, pH and number of electropolymerization cycles were optimized to obtain the highest current signal for the target upon amperometric detection. NAF identification was based on the redox process at +1.1 V (vs pseudo Ag), ascribed to the oxidation of the C-7 side chain. With the optimized modification protocol, a two-fold increase in nafcillin signal could be obtained: the calibration plot in 0.1 M Britton-Robinson buffer pH 4 showed a limit of detection of 80 nM with improved sensitivity and reproducibility (RSD<5 %) compared to the detection at non-modified electrodes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000482596300001 Publication Date 2019-08-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1040-0397 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.851 Times cited 1 Open Access
Notes ; FB and GM devised the study and performed the experiments, FB wrote the original draft of the paper and analysed the data, NS and AvN performed the MS experiments, AF helped with the optimization of the protocol and correction of the first draft, TC and SP performed the rational monomer design, KdW supervised the work and corrected the final draft. All authors gave their suggestions and corrections to the final version of the paper. This work was financially supported by the University of Antwerp (BOF) and the Research Foundation Flanders (FWO). ; Approved Most recent IF: 2.851
Call Number UA @ admin @ c:irua:162870 Serial 5601
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Author De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K.
Title Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine Type A1 Journal article
Year 2018 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 90 Issue 8 Pages 5290-5297
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430512200049 Publication Date 2018-02-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 8 Open Access
Notes ; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:149528 Serial 5693
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Author Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Govindan, M.; Covaci, A.; Van Grieken, R.
Title Spatial monitoring of organohalogen compounds in surface water and sediments of a rural-urban river basin in Tanzania Type A1 Journal article
Year 2013 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 447 Issue Pages 186-197
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract The presence of persistent organic pollutants in Tanzanian environment is not well monitored despite the existing pollution potential from a number of sources. In this study, we investigated for the first time, the concentration profiles of different organohalogen compounds such as organochlorine pesticide residues (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in environmental samples (water and sediments) from the Pangani river basin (PRB). The PRB is one of the largest drainage basins in Tanzania, with its watershed exposed to multiple input sources of trace organic contaminants. Surface water and sediments were sampled from 12 representative stations of diverse characteristics and land-use practices, in three distinct seasons, and extracted by liquidliquid and Soxhlet extraction methods, respectively. Water samples were analyzed by GC-ECD for OCPs only, while sediment samples were analyzed for OCPs, PCBs and PBDEs by GC/MS. Seven compounds, dominated by HCH isomers (5104460 pg/L) and DDT analogs (1601460 pg/L),were detected in the water samples. These concentrations are far below the WHO guidelines for drinking water quality. A total of 42 compounds (8 OCPs, 28 PCB congeners and 6 PBDE congeners) were detected in the sediment samples. Their respective total concentration ranges were 24510,230; 35711,000 and 382175 pg/g dry weight. The spatial distribution patterns and Hierarchical Cluster Analysis reflected the impact of historical agricultural usage in sugarcane plantations (OCPs), and urbanization (PCBs and PBDEs). Risk assessment using sediment quality guidelines indicated no ecotoxicological risks. The results we have found provide preliminary data on levels of the organic contaminants in Pangani river basin as a new insight on the environmental quality of the area.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000317538100022 Publication Date 2013-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.9 Times cited 42 Open Access
Notes ; This research project was funded by the International Foundation for Science (IFS, Project Number W/4945-1). The authors wish to acknowledge the contribution of the Pangani Basin Water Office (PBWO) in Moshi, Tanzania; especially Ms. Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns, and Salim Lyimo in mapping of the study area. The contributions of Mr. Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterization; and Mr. Emmanuel Gwae, of the Government Chemists Laboratory Agency (GCLA) Dar es Salaam, Tanzania, for instrumental analysis of the water samples, are highly appreciated. Harieth Hellar-Kihampa acknowledges financial support from the Belgian Technical Agency (BTC). Govindan Malarvannan and Adrian Covaci acknowledge financial support from the University of Antwerp. ; Approved Most recent IF: 4.9; 2013 IF: 3.163
Call Number UA @ admin @ c:irua:105260 Serial 5836
Permanent link to this record
 

 
Author Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K.
Title Electrochemistry of intact versus degraded cephalosporin antibiotics facilitated by LC–MS analysis Type A1 Journal article
Year 2021 Publication Analytical Chemistry Abbreviated Journal Anal Chem
Volume 93 Issue 4 Pages 2394-2402
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract The electrochemical detection of cephalosporins is a promising approach for the monitoring of cephalosporin levels in process waters. However, this class of antibiotics, like penicillins, is composed of chemically active molecules and susceptible to hydrolysis and aminolysis of the four membered β-lactam ring present. In order to develop a smart monitoring strategy for cephalosporins, the influence of degradation (hydrolysis and aminolysis) on the electrochemical fingerprint has to be taken into account. Therefore, an investigation was carried out to understand the changes of the voltammetric fingerprints upon acidic and alkaline degradation. Changes in fingerprints were correlated to the degradation pathways through the combination of square wave voltammetry and liquid chromatography quadrupole time-of-flight analysis. The characteristic electrochemical signals of the β-lactam ring disappeared upon hydrolysis. Additional oxidation signals that appeared after degradation were elucidated and linked to different degradation products, and therefore, enrich the voltammetric fingerprints with information of the state of the cephalosporins. The applicability of the electrochemical monitoring system was explored by the analysis of the intact and degraded industrial process waters containing the key intermediate 7-aminodeacetoxycephalosporanic acid (7-ADCA). Clearly, the intact process samples exhibited the expected core signals of 7-ADCA and could be quantified, while the degraded samples only showed the newly formed degradation products.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000618089100063 Publication Date 2021-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:176206 Serial 7864
Permanent link to this record
 

 
Author Dirtu, A.C.; Ravindra, K.; Roosens, L.; Van Grieken, R.; Neels, H.; Blust, R.; Covaci, A.
Title Fast analysis of decabrominated diphenyl ether using low-pressure gas chromatography.electron-capture negative ionization mass spectrometry Type A1 Journal article
Year 2008 Publication Journal of chromatography : A Abbreviated Journal
Volume 1186 Issue Pages 295-301
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000254884700024 Publication Date 2007-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9673 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:67546 Serial 7957
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Author Schram, J.; Thiruvottriyur Shanmugam, S.; Sleegers, N.; Florea, A.; Samyn, N.; van Nuijs, A.L.N.; De Wael, K.
Title Local conversion of redox inactive molecules into redox active ones : a formaldehyde based strategy for the electrochemical detection of illicit drugs containing primary and secondary amines Type A1 Journal article
Year 2021 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 367 Issue Pages 137515
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract Electrochemical techniques have evidenced to be highly suitable for the development of portable, rapid and accurate screening methods for the detection of illicit drugs in seized samples. However, the redox inactivity of primary amines, one of the most common functional groups of illicit drugs, masks voltammetric detection in aqueous environment at carbon electrodes and, therefore, leads to false negative results if only these primary amines are present in the structures. This work explores the feasibility of a derivatisation approach that introduces formaldehyde in the measuring conditions in order to achieve methylation, via an Eschweiler-Clarke mechanism, of illicit drugs containing primary and secondary amines, using amphetamine (AMP) and methamphetamine (MET) as model molecules. As a result the electrochemical fingerprint is enriched and thereby the detectability enhanced. A combination of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOFMS) and square-wave voltammetric (SWV) measurements is employed to identify reaction products and link them to the observed redox peaks. Although an alkaline environment (pH 12.0) proved to increase the reaction yield, a richer electrochemical fingerprint (EF) is obtained in neutral conditions (pH 7.0). Similarly, the addition of formate improved the reaction conversion but reduced the EF by eliminating a redox peak that is attributed to side products formed in the absence of formate. To illustrate the applicability, the derivatisation strategy is applied to several prominent illicit drugs containing primary and secondary amines to demonstrate its EF enriching capabilities. Finally, real street samples from forensic seizures are analysed. Overall, this strategy unlocks the detectability of the hitherto undetectable AMP and other drugs only containing primary amines, while strongly facilitating the identification of MET and analogues. These findings are not limited to illicit drugs, the insights can ultimately be applied to other target molecules containing similar functional groups. (C) 2020 Published by Elsevier Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000607620700010 Publication Date 2020-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:176083 Serial 8177
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Author Dirtu, A.C.; Buczyńska, A.J.; Godoi, A.F.L.; Favoreto, R.; Bencs, L.; Potgieter-Vermaak, S.S.; Godoi, R.H.M.; Van Grieken, R.; Van Vaeck, L.
Title Methods, fluxes and sources of gas phase alkyl nitrates in the coastal air Type A1 Journal article
Year 2014 Publication Environmental monitoring and assessment Abbreviated Journal
Volume 186 Issue 10 Pages 6445-6457
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract The daily and seasonal atmospheric concentrations, deposition fluxes and emission sources of a few C3C9 gaseous alkyl nitrates (ANs) at the Belgian coast (De Haan) on the Southern North Sea were determined. An adapted sampler design for low- and high-volume air-sampling, optimized sample extraction and clean-up, as well as identification and quantification of ANs in air samples by means of gas chromatography mass spectrometry, are reported. The total concentrations of ANs ranged from 0.03 to 85 pptv and consisted primarily of the nitro-butane and nitro-pentane isomers. Air mass backward trajectories were calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to determine the influence of main air masses on AN levels in the air. The shorter chain ANs have been the most abundant in the Atlantic/Channel/UK air masses, while longer chain ANs prevailed in continental air. The overall mean N fluxes of the ANs were slightly higher for summer than those for winter-spring, although their contributions to the total nitrogen flux were low. High correlations between AN and HNO2 levels were observed during winter/spring. During summer, the shorter chain ANs correlated well with precipitation. Source apportionment by means of principal component analysis indicated that most of the gas phase ANs could be attributed to traffic/combustion, secondary photochemical formation and biomass burning, although marine sources may also have been present and a contributing factor.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000341497800035 Publication Date 2014-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1420-2026; 1573-2967 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:118906 Serial 8224
Permanent link to this record
 

 
Author van der Linden, V.; Bultinck, E.; de Ruytter, J.; Schalm, O.; Janssens, K.; Devos, W.; Tiri, W.
Title Compositional analysis of 17-18th century archaeological glass fragments, excavated in Mechelen, Belgium: comparison with data from neighboring cities in the Low Countries Type A1 Journal article
Year 2005 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal Nucl Instrum Meth B
Volume 239 Issue 1/2 Pages 100-106
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000233514700013 Publication Date 2005-08-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-583X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.109 Times cited 15 Open Access
Notes Approved Most recent IF: 1.109; 2005 IF: 1.181
Call Number UA @ lucian @ c:irua:56068 Serial 444
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Author Zhang, T.; Schilling, W.; Khan, S.U.; Ching, H.Y.V.; Lu, C.; Chen, J.; Jaworski, A.; Barcaro, G.; Monti, S.; De Wael, K.; Slabon, A.; Das, S.
Title Atomic-level understanding for the enhanced generation of hydrogen peroxide by the introduction of an aryl amino group in polymeric carbon nitrides Type A1 Journal article
Year 2021 Publication Acs Catalysis Abbreviated Journal Acs Catal
Volume 11 Issue 22 Pages 14087-14101
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Heterogeneous catalysts are often & ldquo;black boxes & rdquo; due to the insufficient understanding of the detailed mechanisms at the catalytic sites. An atomic-level elucidation of the processes taking place in those regions is, thus, mandatory to produce robust and selective heterogeneous catalysts. We have improved the description of the whole reactive scenario for polymeric carbon nitrides (PCN) by combining atomic-level characterizations with magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy, classical reactive molecular dynamics (RMD) simulations, and quantum chemistry (QC) calculations. We disclose the structure & minus;property relationships of an ad hoc modified PCN by inserting an aryl amino group that turned out to be very efficient for the production of H2O2. The main advancement of this work is the development of a difluoromethylene-substituted aryl amino PCN to generate H2O2 at a rate of 2.0 mM & middot;h & minus;1 under the irradiation of household blue LEDs and the identification of possible active catalytic sites with the aid of 15N and 19F MAS solid-state NMR without using any expensive labeling reagent. RMD simulations and QC calculations confirm and further extend the experimental descriptions by revealing the role and locations of the identified functionalities, namely, NH linkers, & minus;NH2 terminal groups, and difluoromethylene units, reactants, and products. <comment>Superscript/Subscript Available</comment
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000758012900020 Publication Date 2021-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2155-5435 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.614 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 10.614
Call Number UA @ admin @ c:irua:187276 Serial 7534
Permanent link to this record
 

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

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

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

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

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

 
Author Vermeyen, T.; Brence, J.; Van Echelpoel, R.; Aerts, R.; Acke, G.; Bultinck, P.; Herrebout, W.
Title Exploring machine learning methods for absolute configuration determination with vibrational circular dichroism Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 35 Pages 19781-19789
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Molecular Spectroscopy (MolSpec)
Abstract The added value of supervised Machine Learning (ML) methods to determine the Absolute Configuration (AC) of compounds from their Vibrational Circular Dichroism (VCD) spectra was explored. Among all ML methods considered, Random Forest (RF) and Feedforward Neural Network (FNN) yield the best performance for identification of the AC. At its best, FNN allows near-perfect AC determination, with accuracy of prediction up to 0.995, while RF combines good predictive accuracy (up to 0.940) with the ability to identify the spectral areas important for the identification of the AC. No loss in performance of either model is observed as long as the spectral sampling interval used does not exceed the spectral bandwidth. Increasing the sampling interval proves to be the best method to lower the dimensionality of the input data, thereby decreasing the computational cost associated with the training of the models.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000691366500001 Publication Date 2021-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.123
Call Number UA @ admin @ c:irua:180290 Serial 7951
Permanent link to this record
 

 
Author van Meel, K.; Horemans, B.; Krata, A.; Bencs, L.; Buczyńska, A.J.; Dirtu, A.C.; Worobiec, A.; Van Grieken, R.
Title Elemental concentrations in aerosols at the Belgian coast versus seasons and air mass trajectories Type A1 Journal article
Year 2010 Publication Environmental chemistry letters Abbreviated Journal
Volume 8 Issue 2 Pages 157-163
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP); Toxicological Centre
Abstract Marine aerosols have extensively been monitored in the framework of a research project to investigate the inorganic and organic nutrient fluxes of the atmospheric nitrogen input into the North Sea. As a part of this project bulk analysis was also performed by energy dispersive X-ray fluorescence (EDXRF) on a total of 366 samples in order to provide detailed elemental composition. Samples have been clustered per campaign and differences were related to backward trajectories. Elements as Cl, Si, and S appeared to be the best tracers for coastal aerosols. Therefore they have been chosen to represent each campaign and to map the seasonal variations. It is clear that Cl is an excellent tracer for oceanic trajectories, while a less clear correlation between the soil dust components and the air mass trajectories is found.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000277786900007 Publication Date 2009-02-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1610-3653 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:82494 Serial 7893
Permanent link to this record
 

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

 
Author Krupińska, B.; Worobiec, A.; Rotondo, G.G.; Novaković, V.; Kontozova, V.; Ro, C.-U.; Van Grieken, R.; De Wael, K.
Title Assessment of the air quality (NO2, SO2, O3 and particulate matter) in the Plantin-Moretus Museum/Print Room in Antwerp, Belgium, in different seasons of the year Type A1 Journal article
Year 2012 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 102 Issue 1 Pages 49-53
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract The Plantin-Moretus Museum/Print Room in Antwerp, Belgium, gathers one of the most precious collections of typographical material and old printed books in the world. Rich decorations of this former printing-house and the history of the building itself underline its uniqueness. The cultural heritage (CH) objects collected in the museum, in particular books and manuscripts are vulnerable to the atmospheric pollution and can be irreversibly damaged. To assess the air quality inside the museum, four consecutive sampling campaigns were performed in each season of the year. The gas monitoring of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) was carried out outside the building, in galleries and in showcases by means of using diffusive samplers. The particulate matter (PM) was collected in bulk form and as single particles and then analysed with use of energy dispersive X-ray fluorescence (EDXRF) and electron probe micro-analyser (EPMA), respectively. The museum complex turned out to show good protection against gaseous pollutants, especially SO2 and O3. The concentrations of these pollutants were significantly reduced inside the building in comparison to the outdoor ones. Similar protective character of the museum complex was established in case of the coarse fraction of PM; however with some limitations. Single particle analysis showed that the relative abundance of carbon-rich particles inside the museum was greater than outside. Moreover, these particles contributed more to the fine fraction of PM than to the coarse fraction. Therefore, for better preservation of cultural heritage, special attention should be paid to the small particles and their distribution within the museum.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000301559100007 Publication Date 2011-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 25 Open Access
Notes ; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ; Approved Most recent IF: 3.034; 2012 IF: 2.879
Call Number UA @ admin @ c:irua:94466 Serial 5483
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Author Worobiec, A.; Potgieter-Vermaak, S.S.; Berghmans, P.; Winkler, H.; Burger, R.; Van Grieken, R.
Title Air particulate emissions in developing countries : a case study in South Africa Type A1 Journal article
Year 2011 Publication Analytical letters Abbreviated Journal
Volume 44 Issue 11 Pages 1907-1924
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Atmospheric aerosols were collected during the winter in Bethlehem, South Africa. The particulate mass concentrations, ambient carbon mass concentrations, and chemical composition of various particulate fractions showed that the area is highly polluted. The fine particle mass concentrations peaked at 1000 µg/m3 for PM2.5. Ambient carbon mass concentrations ranged from 20 to 40 µg/m3. Single particle analysis confirmed that the fine particle fraction was dominated by organic particles. The topographical conditions, causing a low inversion, together with the high amounts of emissions from biomass burning, result in unacceptable levels of air pollution and pose a considerable health threat to the population.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000294602300006 Publication Date 2011-08-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2719 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:91079 Serial 7429
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Author Horemans, B.; Worobiec, A.; Buczyńska, A.; van Meel, K.; Van Grieken, R.
Title Airborne particulate matter and BTEX in office environments Type A1 Journal article
Year 2008 Publication Journal of environmental monitoring Abbreviated Journal
Volume 10 Issue 7 Pages 867-876
Keywords (down) A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000257425300010 Publication Date 2008-06-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1464-0325; 1464-0333 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:69425 Serial 7434
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