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Author Dik, J.; Janssens, K.; van der Snickt, G.; van der Loeff, L.; Rickers, K.; Cotte, M.
  Title Visualization of a lost painting by Vincent van Gogh using synchrotron radiation based X-ray fluorescence elemental mapping Type A1 Journal article
  Year 2008 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume 80 Issue 16 Pages 6436-6442
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Vincent van Gogh (1853−1890), one of the founding fathers of modern painting, is best known for his vivid colors, his vibrant painting style, and his short but highly productive career. His productivity is even higher than generally realized, as many of his known paintings cover a previous composition. This is thought to be the case in one-third of his early period paintings. Van Gogh would often reuse the canvas of an abandoned painting and paint a new or modified composition on top. These hidden paintings offer a unique and intimate insight into the genesis of his works. Yet, current museum-based imaging tools are unable to properly visualize many of these hidden images. We present the first-time use of synchrotron radiation based X-ray fluorescence mapping, applied to visualize a womans head hidden under the work Patch of Grass by Van Gogh. We recorded decimeter-scale, X-ray fluorescence intensity maps, reflecting the distribution of specific elements in the paint layers. In doing so we succeeded in visualizing the hidden face with unprecedented detail. In particular, the distribution of Hg and Sb in the red and light tones, respectively, enabled an approximate color reconstruction of the flesh tones. This reconstruction proved to be the missing link for the comparison of the hidden face with Van Goghs known paintings. Our approach literally opens up new vistas in the nondestructive study of hidden paint layers, which applies to the oeuvre of Van Gogh in particular and to old master paintings in general.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000258448100039 Publication Date 2008-07-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.32 Times cited 178 Open Access
  Notes Approved Most recent IF: 6.32; 2008 IF: 5.712
  Call Number UA @ admin @ c:irua:74466 Serial 5906
Permanent link to this record
 

 
Author Neven, L.; Barich, H.; Ching, H.Y.V.; Khan, S.U.; Colomier, C.; Patel, H.H.; Gorun, S.M.; Verbruggen, S.; Van Doorslaer, S.; De Wael, K.
  Title Correlation between the fluorination degree of perfluorinated zinc phthalocyanines, their singlet oxygen generation ability, and their photoelectrochemical response for phenol sensing Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume 94 Issue 13 Pages 5221-5230
  Keywords A1 Journal article; Organic synthesis (ORSY); Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Electron-withdrawing perfluoroalkyl peripheral groups grafted on phthalocyanine (Pc) macrocycles improve their single-site isolation, solubility, and resistance to self-oxidation, all beneficial features for catalytic applications. A high degree of fluorination also enhances the reducibility of Pcs and could alter their singlet oxygen (1O2) photoproduction. The ethanol/toluene 20:80 vol % solvent mixture was found to dissolve perfluorinated FnPcZn complexes, n = 16, 52, and 64, and minimize the aggregation of the sterically unencumbered F16PcZn. The 1O2 production ability of FnPcZn complexes was examined using 9,10-dimethylanthracene (DMA) and 2,2,6,6-tetramethylpiperidine (TEMP) in combination with UV–vis and electron paramagnetic resonance (EPR) spectroscopy, respectively. While the photoreduction of F52PcZn and F64PcZn in the presence of redox-active TEMP lowered 1O2 production, DMA was a suitable 1O2 trap for ranking the complexes. The solution reactivity was complemented by solid-state studies via the construction of photoelectrochemical sensors based on TiO2-supported FnPcZn, FnPcZn|TiO2. Phenol photo-oxidation by 1O2, followed by its electrochemical reduction, defines a redox cycle, the 1O2 production having been found to depend on the value of n and structural features of the supported complexes. Consistent with solution studies, F52PcZn was found to be the most efficient 1O2 generator. The insights on reactivity testing and structural–activity relationships obtained may be useful for designing efficient and robust sensors and for other 1O2-related applications of FnPcZn.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000786254500002 Publication Date 2022-03-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 7.4
  Call Number UA @ admin @ c:irua:187522 Serial 7141
Permanent link to this record
 

 
Author Khan, S.U.; Trashin, S.; Beltran, V.; Korostei, Y.S.; Pelmus, M.; Gorun, S.M.; Dubinina, T., V.; Verbruggen, S.W.; De Wael, K.
  Title Photoelectrochemical behavior of phthalocyanine-sensitized TiO₂ in the presence of electron-shuttling mediators Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume 94 Issue 37 Pages 12723-12731
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Dye-sensitized TiO(2 )has found many applications for dye sensitized solar cells (DSSC), solar-to-chemical energy conversion, water/air purification systems, and (electro)chemical sensors. We report an electrochemical system for testing dye-sensitized materials that can be utilized in photoelectrochemical (PEC) sensors and energy conversion. Unlike related systems, the reported system does not require a direct electron transfer from semiconductors to electrodes. Rather, it relies on electron shuttling by redox mediators. A range of model photocatalytic materials were prepared using three different TiO2 materials (P25, P90, and PC500) and three sterically hindered phthalocyanines (Pcs) with electron-rich tert-butyl substituents (t-Bu4PcZn, t-Bu4PcAlCl, and t-Bu4PcH2). The materials were compared with previously developed TiO(2 )modified by electron-deficient, also sterically hindered fluorinated phthalocyanine F64PcZn, a singlet oxygen (O-1(2)) producer, as well as its metal-free derivative, F64PcH2. The PEC activity depended on the redox mediator, as well as the type of TiO2 and Pc. By comparing the responses of one-electron shuttles, such as K4Fe(CN)(4), and O-1(2)-reactive electron shuttles, such as phenol, it is possible to reveal the action mechanism of the supported photosensitizers, while the overall activity can be assessed using hydroquinone. t-Bu4PcAlCl showed significantly lower blank responses and higher specific responses toward chlorophenols compared to t-Bu4PcZn due to the electron-withdrawing effect of the Al3+ metal center. The combination of reactivity insights and the need for only microgram amounts of sensing materials renders the reported system advantageous for practical applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000855284300001 Publication Date 2022-09-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 7.4
  Call Number UA @ admin @ c:irua:190602 Serial 7190
Permanent link to this record
 

 
Author Markowicz, A.A.; Storms, H.M.; Van Grieken, R.E.
  Title Absorption correction in electron probe x-ray microanalysis of thin samples Type A1 Journal article
  Year 1986 Publication Analytical chemistry Abbreviated Journal
  Volume 58 Issue 7 Pages 1282-1285
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1986C594100007 Publication Date 2005-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:116524 Serial 7409
Permanent link to this record
 

 
Author Van Dyck, P.M.; Van Grieken, R.E.
  Title Absorption correction via scattered radiation in energy-dispersive X-ray fluorescence analysis for samples of variable composition and thickness Type A1 Journal article
  Year 1980 Publication Analytical chemistry Abbreviated Journal
  Volume 52 Issue 12 Pages 1859-1864
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1980KJ65700021 Publication Date 2005-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:116516 Serial 7410
Permanent link to this record
 

 
Author Blockhuys, F.; Claes, M.; Van Grieken, R.; Geise, H.J.
  Title Assessing the molecular weight of a conducting polymer by grazing emission XRF Type A1 Journal article
  Year 2000 Publication Analytical chemistry Abbreviated Journal
  Volume 72 Issue 14 Pages 3366-3368
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000088347100054 Publication Date 2002-07-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:27915 Serial 7497
Permanent link to this record
 

 
Author Markowicz, A.A.; Storms, H.M.; Van Grieken, R.E.
  Title Bremsstrahlung background in electron-probe X-ray-microanalysis of thin films Type A1 Journal article
  Year 1985 Publication Analytical chemistry Abbreviated Journal
  Volume 57 Issue 14 Pages 2885-2889
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1985AVD0100033 Publication Date 2005-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:113616 Serial 7567
Permanent link to this record
 

 
Author Van Grieken, R.E.; Bresseleers, C.M.; Vanderborght, B.M.
  Title Chelex-100 ion-exchange filter membranes for preconcentration in x-ray-fluorescence analysis of water Type A1 Journal article
  Year 1977 Publication Analytical chemistry Abbreviated Journal
  Volume 49 Issue 9 Pages 1326-1331
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1977DP25600011 Publication Date 2005-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:113632 Serial 7639
Permanent link to this record
 

 
Author Monico, L.; Cotte, M.; Vanmeert, F.; Amidani, L.; Janssens, K.; Nuyts, G.; Garrevoet, J.; Falkenberg, G.; Glatzel, P.; Romani, A.; Miliani, C.
  Title Damages induced by synchrotron radiation-based X-ray microanalysis in chrome yellow paints and related Cr-compounds : assessment, quantification, and mitigation strategies Type A1 Journal article
  Year 2020 Publication Analytical Chemistry Abbreviated Journal Anal Chem
  Volume 92 Issue 20 Pages 14164-14173
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Synchrotron radiation (SR)-based X-ray methods are powerful analytical tools for several purposes. They are widely used to probe the degradation mechanisms of inorganic artists' pigments in paintings, including chrome yellows (PbCr1-xSxO4; 0 <= x <= 0.8), a class of compounds often found in Van Gogh masterpieces. However, the high intensity and brightness of SR beams raise important issues regarding the potential damage inflicted on the analyzed samples. A thorough knowledge of the SR X-ray sensitivity of each class of pigment in the painting matrix is therefore required to find analytical strategies that seek to minimize the damage for preserving the integrity of the analyzed samples and to avoid data misinterpretation. Here, we employ a combination of Cr K-edge X-ray absorption near-edge structure spectroscopy, Cr-K-beta X-ray emission spectroscopy, and X-ray diffraction to monitor and quantify the effects of SR X-rays on the stability of chrome yellows and related Cr compounds and to define mitigation strategies. We found that the SR X-ray beam exposure induces changes in the oxidation state and local coordination environment of Cr ions and leads to a loss of the compound's crystalline structure. The extent of X-ray damage depends on some intrinsic properties of the samples (chemical composition of the pigment and the presence/absence and nature of the binder). It can be minimized by optimizing the overall fluence/dose released to the samples and by working in vacuum and under cryogenic conditions.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000584418100072 Publication Date 2020-09-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access
  Notes Approved Most recent IF: 7.4; 2020 IF: 6.32
  Call Number UA @ admin @ c:irua:174363 Serial 7754
Permanent link to this record
 

 
Author van Meel, K.; Smekens, A.; Behets, M.; Kazandjian, P.; Van Grieken, R.
  Title Determination of platinum, palladium, and rhodium in automotive catalysts using high-energy secondary target X-ray fluorescence spectrometry Type A1 Journal article
  Year 2007 Publication Analytical chemistry Abbreviated Journal
  Volume 79 Issue 16 Pages 6383-6389
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000248993300042 Publication Date 2007-07-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:64781 Serial 7784
Permanent link to this record
 

 
Author Camerani, M.C.; Somogyi, A.; Vekemans, B.; Ansell, S.; Simionovici, A.S.; Steenari, B.-M.; Panas, I.
  Title Determination of the cd-bearing phases in municipal solid waste and Biomass single fly ash particles using SR-mu XRF Spectroscopy Type A1 Journal article
  Year 2007 Publication Analytical chemistry Abbreviated Journal
  Volume 79 Issue 17 Pages 6496-6506
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000249242900017 Publication Date 2007-08-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:66600 Serial 7790
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 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 (down) 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 Van Dyck, P.M.; Török, S.B.; Van Grieken, R.E.
  Title Enhancement effect in X-ray fluorescence analysis of environmental samples of medium thickness Type A1 Journal article
  Year 1986 Publication Analytical chemistry Abbreviated Journal
  Volume 58 Issue 8 Pages 1761-1766
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1986C955500040 Publication Date 2005-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:116522 Serial 7915
Permanent link to this record
 

 
Author Vanderborght, B.M.; Van Grieken, R.E.
  Title Enrichment of trace metals in water by adsorption on activated carbon Type A1 Journal article
  Year 1977 Publication Analytical chemistry Abbreviated Journal
  Volume 49 Issue 2 Pages 311-316
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos Publication Date
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record
  Impact Factor Times cited Open Access
  Notes Approved no
  Call Number UA @ admin @ c:irua:116513 Serial 7923
Permanent link to this record
 

 
Author Wiorek, A.; Parrilla, M.; Cuartero, M.; Crespo, G.A.
  Title Epidermal patch with glucose biosensor : pH and temperature correction toward more accurate sweat analysis during sport practice Type A1 Journal article
  Year 2020 Publication Analytical Chemistry Abbreviated Journal Anal Chem
  Volume 92 Issue 14 Pages 10153-10161
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract We present an epidermal patch for glucose analysis in sweat incorporating for the first time pH and temperature correction according to local dynamic fluctuations in sweat during on-body tests. This sort of correction is indeed the main novelty of the paper, being crucial toward reliable measurements in every sensor based on an enzymatic element whose activity strongly depends on pH and temperature. The results herein reported for corrected glucose detection during on-body measurements are supported by a two-step validation protocol: with the biosensor operating off- and on-bodily, correlating the results with UV-vis spectrometry and/or ion chromatography. Importantly, the wearable device is a flexible skin patch that comprises a microfluidic cell designed with a sweat collection zone coupled to a fluidic channel in where the needed electrodes are placed: glucose biosensor, pH potentiometric electrode and a temperature sensor. The glucose biosensor presents a linear range of response within the expected physiological levels of glucose in sweat (10-200 mu M), and the calibration parameters are dynamically adjusted to any change in pH and temperature during the sport practice by means of a new “correction approach”. In addition, the sensor displays a fast response time, appropriate selectivity, and excellent reversibility. A total of 9 validated on-body tests are presented: the outcomes revealed a great potential of the wearable glucose sensor toward the provision of reliable physiological data linked to individuals during sport activity. In particular, the developed “correction approach” is expected to impact into the next generation of wearable devices that digitalize physiological activities through chemical information in a trustable manner for both sport and healthcare applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000554986200089 Publication Date 2020-06-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access
  Notes Approved Most recent IF: 7.4; 2020 IF: 6.32
  Call Number UA @ admin @ c:irua:175265 Serial 7931
Permanent link to this record
 

 
Author Marguí, E.; Fontàs, C.; van Meel, K.; Van Grieken, R.; Queralt, I.; Hidalgo, M.
  Title High-energy polarized-beam energy-dispersive X-ray fluorescence analysis combined with activated thin layers for cadmium determination at trace levels in complex environmental liquid samples Type A1 Journal article
  Year 2008 Publication Analytical chemistry Abbreviated Journal
  Volume 80 Issue 7 Pages 2357-2364
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000254593500015 Publication Date 2008-03-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:68425 Serial 8032
Permanent link to this record
 

 
Author Marguí, E.; van Meel, K.; Van Grieken, R.; Buendía, A.; Fontás, C.; Hidalgo, M.; Queralt, I.
  Title Method for the determination of Pd-catalyst residues in active pharmaceutical ingredients by means of high-energy polarized-beam energy dispersive X-ray fluorescence Type A1 Journal article
  Year 2009 Publication Analytical chemistry Abbreviated Journal
  Volume 81 Issue 4 Pages 1404-1410
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract In medicinal chemistry, Pd is perhaps the most-widely utilized precious metal, as catalyst in reactions which represent key transformations toward the synthesis of new active pharmaceutical ingredients (APIs). The disadvantage of this metal-catalyzed chemistry is that expensive and toxic metal residues are invariably left bound to the desired product. Thus, stringent regulatory guidelines exist for the amount of residual Pd that a drug candidate is allowed to contain. In this work, a rapid and simple method for the determination of Pd in API samples by high-energy polarized-beam energy dispersive X-ray fluorescence spectrometry has been developed and validated according to the specification limits of current legislation (10 mg kg−1 Pd) and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines). Sample and calibration standards preparation includes a first step of homogenization and then, in a second step, the pressing of the powdered material into pellets without any chemical treatment. The use of several synthetic calibration standards made of cellulose to simulate the API matrix appears to be an effective means to obtain reliable calibration curves with a good spread of data points over the working range. With the use of the best measuring conditions, the limit of detection (0.11 mg kg−1 Pd) as well as the limit of quantitation (0.37 mg kg−1 Pd) achieved meet rigorous requirements. The repeatability of the XRF measurement appeared to be less than 2%, while the precision of the whole method was around 7%. Trueness was evaluated by analyzing spiked API samples at the level of the specification limit and calculating the recovery factor, which was better than 95%. To study the applicability of the developed methodology for the intended purpose, three batches of the studied API were analyzed for their Pd content, and the attained results were comparable to those obtained by the daily routine method (acid digestion plus atomic spectroscopy) used in most pharmaceutical laboratories.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000263319000015 Publication Date 2009-01-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:74340 Serial 8220
Permanent link to this record
 

 
Author Trashin, S.; Morales-Yánez, F.; Thiruvottriyur Shanmugam, S.; Paredis, L.; Carrión, E.N.; Sariego, I.; Muyldermans, S.; Polman, K.; Gorun, S.M.; De Wael, K.
  Title Nanobody-based immunosensor detection enhanced by photocatalytic-electrochemical redox cycling Type A1 Journal article
  Year 2021 Publication Analytical Chemistry Abbreviated Journal Anal Chem
  Volume 93 Issue 40 Pages 13606-13614
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Detection of antigenic biomarkers present in trace amounts is of crucial importance for medical diagnosis. A parasitic disease, human toxocariasis, lacks an adequate diagnostic method despite its worldwide occurrence. The currently used serology tests may stay positive even years after a possibly unnoticed infection, whereas the direct detection of a re-infection or a still active infection remains a diagnostic challenge due to the low concentration of circulating parasitic antigens. We report a time-efficient sandwich immunosensor using small recombinant single-domain antibodies (nanobodies) derived from camelid heavy-chain antibodies specific to Toxocara canis antigens. An enhanced sensitivity to pg/mL levels is achieved by using a redox cycle consisting of a photocatalytic oxidation and electrochemical reduction steps. The photocatalytic oxidation is achieved by a photosensitizer generating singlet oxygen (1O2) that, in turn, readily reacts with p-nitrophenol enzymatically produced under alkaline conditions. The photooxidation produces benzoquinone that is electrochemically reduced to hydroquinone, generating an amperometric response. The light-driven process could be easily separated from the background, thus making amperometric detection more reliable. The proposed method for detection of the toxocariasis antigen marker shows superior performances compared to other detection schemes with the same nanobodies and outperforms by at least two orders of magnitude the assays based on regular antibodies, thus suggesting new opportunities for electrochemical immunoassays of challenging low levels of antigens.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000708550500025 Publication Date 2021-09-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.32 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 6.32
  Call Number UA @ admin @ c:irua:181795 Serial 8290
Permanent link to this record
 

 
Author Choël, M.; Deboudt, K.; Osán, J.; Flament, P.; Van Grieken, R.
  Title Quantitative determination of low-Z elements in single atmospheric particles on boron substrates by automated scanning electron microscopy: energy-dispersive X-ray spectrometry Type A1 Journal article
  Year 2005 Publication Analytical chemistry Abbreviated Journal
  Volume 77 Issue 17 Pages 5686-5692
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000231652300046 Publication Date 2005-08-31
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:53593 Serial 8443
Permanent link to this record
 

 
Author Liu, Y.; Cánovas, R.; Crespo, G.A.; Cuartero, M.
  Title Thin-layer potentiometry for creatinine detection in undiluted human urine using ion-exchange membranes as barriers for charged interferences Type A1 Journal article
  Year 2020 Publication Analytical Chemistry Abbreviated Journal Anal Chem
  Volume 92 Issue 4 Pages 3315-3323
  Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Herein, thin-layer potentiometry combined with ion-exchange membranes as barriers for charged interferences is demonstrated for the analytical detection of creatinine (CRE) in undiluted human urine. Briefly, CRE diffuses through an anion-exchange membrane (AEM) from a sample contained in one fluidic compartment to a second reservoir, containing the enzyme CRE deiminase. There, CRE reacts with the enzyme, and the formation of ammonium is dynamically monitored by potentiometric ammonium-selective electrodes. This analytical concept is integrated into a lab-on-a-chip microfluidic cell that allows for a high sample throughput and the operation under stop-flow mode, which allows CRE to passively diffuse across the AEM. Conveniently, positively charged species (i.e., potassium, sodium, and ammonium, among others) are repelled by the AEM and never reach the ammonium-selective electrodes; thus, possible interference in the response can be avoided. As a result, the dynamic potential response of the electrodes is entirely ascribed to the stoichiometric formation of ammonium. The new CRE biosensor exhibits a Nernstian slope, within a linear range of response from 1 to 50 mM CRE concentration. As expected, the response time (15–60 min) primarily depends on the CRE diffusion across the AEM. CRE analysis in urine samples displayed excellent results, without requiring sample pretreatment (before the introduction of the sample in the microfluidic chip) and with high compatibility with development into a potential point-of-care clinical tool. In an attempt to decrease the analysis time, the presented analytical methodology for CRE detection is translated into an all-solid-state platform, in which the enzyme is immobilized on the surface of the ammonium-selective electrode and with the AEM on top. While more work is necessary in this direction, the CRE sensor appears to be promising for CRE analysis in both urine and blood.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos Publication Date 2020-01-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record
  Impact Factor 7.4 Times cited Open Access
  Notes Approved Most recent IF: 7.4; 2020 IF: 6.32
  Call Number UA @ admin @ c:irua:184380 Serial 8667
Permanent link to this record
 

 
Author Vincze, L.; Vekemans, B.; Brenker, F.E.; Falkenberg, G.; Rickers, K.; Somogyi, A.; Kersten, M.; Adams, F.
  Title Three-dimensional trace element analysis by confocal X-ray microfluorescence imaging Type A1 Journal article
  Year 2004 Publication Analytical chemistry Abbreviated Journal
  Volume 76 Issue 22 Pages 6786-6791
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000225076400034 Publication Date 2004-11-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:49817 Serial 8669
Permanent link to this record
 

 
Author Török, S.; Labar, J.; Schmeling, M.; Van Grieken, R.
  Title X-ray spectrometry Type A1 Journal article
  Year 1998 Publication Analytical chemistry Abbreviated Journal
  Volume 70 Issue Pages 495r-517r
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000074161100020 Publication Date
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x 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:20967 Serial 8776
Permanent link to this record
 

 
Author Ma, X.; Pavlidis, G.; Dillon, E.; Beltran, V.; Schwartz, J.J.; Thoury, M.; Borondics, F.; Sandt, C.; Kjoller, K.; Berrie, B.H.; Centrone, A.
  Title Micro to nano : multiscale IR analyses reveal zinc soap heterogeneity in a 19th-century painting by Corot Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal
  Volume 94 Issue 7 Pages 3103-3110
  Keywords A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Formation and aggregation of metal carboxylates (metal soaps) can degrade the appearance and integrity of oil paints, challenging efforts to conserve painted works of art. Endeavors to understand the root cause of metal soap formation have been hampered by the limited spatial resolution of Fourier transform infrared microscopy (mu-FTIR). We overcome this limitation using optical photothermal infrared spectroscopy (O-PTIR) and photothermal-induced resonance (PTIR), two novel methods that provide IR spectra with approximate to 500 and approximate to 10 nm spatial resolutions, respectively. The distribution of chemical phases in thin sections from the top layer of a 19th-century painting is investigated at multiple scales (mu-FTIR approximate to 10(2) mu m(3), O-PTIR approximate to 10(-1) mu m(3), PTIR approximate to 10(-5) mu m(3)). The paint samples analyzed here are found to be mixtures of pigments (cobalt green, lead white), cured oil, and a rich array of intermixed, small (often << 0.1 mu m(3)) zinc soap domains. We identify Zn stearate and Zn oleate crystalline soaps with characteristic narrow IR peaks (approximate to 1530-1558 cm(-1)) and a heterogeneous, disordered, water-permeable, tetrahedral zinc soap phase, with a characteristic broad peak centered at approximate to 1596 cm(-1). We show that the high signal-to-noise ratio and spatial resolution afforded by O-PTIR are ideal for identifying phase-separated (or locally concentrated) species with low average concentration, while PTIR provides an unprecedented nanoscale view of distributions and associations of species in paint. This newly accessible nanocompositional information will advance our knowledge of chemical processes in oil paint and will stimulate new art conservation practices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000766206700011 Publication Date 2022-02-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS full record; WoS citing articles
  Impact Factor Times cited Open Access OpenAccess
  Notes Approved no
  Call Number UA @ admin @ c:irua:187380 Serial 8897
Permanent link to this record
 

 
Author Steijlen, A.S.M.; Parrilla, M.; Van Echelpoel, R.; De Wael, K.
  Title Dual microfluidic sensor system for enriched electrochemical profiling and identification of illicit drugs on-site Type A1 Journal article
  Year 2024 Publication Analytical chemistry Abbreviated Journal
  Volume 96 Issue 1 Pages 590-598
  Keywords A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Electrochemical sensors have emerged as a new analytical tool for illicit drug detection to facilitate ultrafast and accurate identification of suspicious compounds on-site. Drugs of abuse can be identified using their unique voltammetric fingerprint at a given pH. Today, the right buffer solution is manually selected based on drug appearance, and in some cases, a consecutive analysis in two different pH solutions is required. In this work, we present a disposable microfluidic multichannel sensor system that automatically records fingerprints in two pH solutions (e.g., pH 5 and pH 12). This system has two advantages. It will overcome the manual selection of a buffer solution at the right pH, decrease analysis time, and minimize the risk of human errors. Second, the combination of two fingerprints, the superfingerprint, contains more detailed information about the samples, which enhances the selectivity of the analytical technique. First, real-time pH measurements proved that the sample can be brought to the desired pH within a minute. Subsequently, an electrochemical study on the microfluidic platform with 1 mM illicit drug standards of MDMA, cocaine, heroin, and methamphetamine showed that the characteristic voltammetric fingerprints and peak potentials are reproducible, also in the presence of common cutting agents. Finally, the microfluidic concept was validated with real confiscated samples, showing promising results for the user-friendly identification of drugs of abuse. In short, this paper presents a successful proof-of-concept study of a multichannel microfluidic sensor system to enrich the fingerprints of illicit drugs at pH 5 and pH 12, thus providing a low-cost, portable, and rapid identification system of illicit drugs with minimal user intervention.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 001139443500001 Publication Date 2023-12-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access Not_Open_Access
  Notes Approved Most recent IF: 7.4; 2024 IF: 6.32
  Call Number UA @ admin @ c:irua:201877 Serial 9024
Permanent link to this record
 

 
Author Aghaei, M.; Lindner, H.; Bogaerts, A.
  Title Ion Clouds in the Inductively Coupled Plasma Torch: A Closer Look through Computations Type A1 Journal article
  Year 2016 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume 88 Issue 88 Pages 8005-8018
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract We have computationally investigated the introduction of copper elemental particles in an inductively coupled plasma torch connected to a sampling cone, including for the first time the ionization of the sample. The sample is inserted as liquid particles, which are followed inside the entire torch, i.e., from the injector inlet up to the ionization and reaching the sampler. The spatial position of the ion clouds inside the torch as well as detailed information on the copper species fluxes at the position of the sampler orifice and the exhausts of the torch are provided. The effect of on- and off-axis injection is studied. We clearly show that the ion clouds of on-axis injected material are located closer to the sampler with less radial diffusion. This guarantees a higher transport efficiency through the sampler cone. Moreover, our model reveals the optimum ranges of applied power and flow rates, which ensure the proper position of ion clouds inside the torch, i.e., close enough to the sampler to increase the fraction that can enter the mass spectrometer and with minimum loss of material toward the exhausts as well as a sufficiently high plasma temperature for efficient ionization.
  Address Research Group PLASMANT, Chemistry Department, University of Antwerp , Universiteitsplein 1, 2610 Antwerp, Belgium
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language English Wos 000381654800020 Publication Date 2016-07-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.32 Times cited 9 Open Access
  Notes The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO), Grant Number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UA. Approved Most recent IF: 6.32
  Call Number PLASMANT @ plasmant @ c:irua:135644 Serial 4293
Permanent link to this record
 

 
Author Fuchs, J.; Aghaei, M.; Schachel, T.D.; Sperling, M.; Bogaerts, A.; Karst, U.
  Title Impact of the Particle Diameter on Ion Cloud Formation from Gold Nanoparticles in ICPMS Type A1 Journal article
  Year 2018 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume 90 Issue 17 Pages 10271-10278
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The unique capabilities of microsecond dwell time (DT) single-particle inductively coupled plasma mass spectrometry (spICPMS) were utilized to characterize the cloud of ions generated from the introduction of suspensions of gold nanoparticles (AuNPs) into the plasma. A set of narrowly distributed particles with diameters ranging from 15.4 to 100.1 nm was synthesized and characterized according to established protocols. Statistically significant numbers of the short transient spICPMS events were evaluated by using 50 μs DT for their summed intensity, maximum intensity, and duration, of which all three were found to depend on the particle diameter. The summed intensity increases from 10 to 1661 counts and the maximum intensity from 6 to 309 counts for AuNPs with diameters from 15.4 to 83.2 nm. The event duration rises from 322 to 1007 μs upon increasing AuNP diameter. These numbers represent a comprehensive set of key data points of the ion clouds generated in ICPMS from AuNPs. The extension of event duration is of high interest to appoint the maximum possible particle number concentration at which separation of consecutive events in spICPMS can still be achieved. Moreover, the combined evaluation of all above-mentioned ion cloud characteristics can explain the regularly observed prolonged single-particle events. The transport and ionization behavior of AuNPs in the ICP was also computationally modeled to gain insight into the size-dependent signal generation. The simulated data reveals that the plasma temperature, and therefore the point of ionization of the particles, is the same for all diameters. However, the maximum number density of Au+, as well as the extent of the ion cloud, depends on the particle diameter, in agreement with the experimental data, and it provides an adequate explanation for the observed ion cloud characteristics.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000444060600028 Publication Date 2018-09-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.32 Times cited 5 Open Access OpenAccess
  Notes We thank Dr. Harald Rösner from the Institute of Materials Physics of the University of Münster for the TEM imaging. Approved Most recent IF: 6.32
  Call Number PLASMANT @ plasmant @c:irua:153651 Serial 5057
Permanent link to this record
 

 
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
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000580426800091 Publication Date 2020-10-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 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
 

 
Author Aghaei, M.; Bogaerts, A.
  Title Flowing Atmospheric Pressure Afterglow for Ambient Ionization: Reaction Pathways Revealed by Modeling Type A1 Journal article
  Year 2021 Publication Analytical Chemistry Abbreviated Journal Anal Chem
  Volume 93 Issue 17 Pages 6620-6628
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract We describe the plasma chemistry in a helium flowing atmospheric pressure afterglow (FAPA) used for analytical spectrometry, by means of a quasione-dimensional (1D) plasma chemical kinetics model. We study the effect of typical impurities present in the feed gas, as well as the afterglow in ambient humid air. The model provides the species density profiles in the discharge and afterglow regions and the chemical pathways. We demonstrate that H, N, and O atoms are formed in the discharge region, while the dominant reactive neutral species in the afterglow are O3 and NO. He* and He2* are responsible for Penning ionization of O2, N2, H2O, H2, and N, and especially O and H atoms. Besides, He2+ also contributes to ionization of N2, O2, H2O, and O through charge transfer reactions. From the pool of ions created in the discharge, NO+ and (H2O)3H+ are the dominant ions in the afterglow. Moreover, negatively charged clusters, such as NO3H2O− and NO2H2O−, are formed and their pathway is discussed as well. Our model predictions are in line with earlier observations in the literature about the important reagent ions and provide a comprehensive overview of the underlying pathways. The model explains in detail why helium provides a high analytical sensitivity because of high reagent ion formation by both Penning ionization and charge transfer. Such insights are very valuable for improving the analytical performance of this (and other) ambient desorption/ionization source(s).
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000648505900008 Publication Date 2021-05-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2700 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.32 Times cited Open Access OpenAccess
  Notes Fonds Wetenschappelijk Onderzoek, 6713 ; The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO) grant number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the UA. The authors also thank J. T. Shelley for providing experimental data for the gas velocity behind the anode disk and before the mass spectrometer interface, to validate our model. Approved Most recent IF: 6.32
  Call Number PLASMANT @ plasmant @c:irua:178126 Serial 6762
Permanent link to this record
 

 
Author Baez, J.F.; Compton, M.; Chahrati, S.; Cánovas, R.; Blondeau, P.; Andrade, F.J.
  Title Controlling the mixed potential of polyelectrolyte-coated platinum electrodes for the potentiometric detection of hydrogen peroxide Type A1 Journal article
  Year 2020 Publication Analytica Chimica Acta Abbreviated Journal Anal Chim Acta
  Volume 1097 Issue Pages 204-213
  Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract The use of a Pt electrode coated with a layer of Nafion has been described in previous works as an attractive way to perform the potentiometric detection of hydrogen peroxide. Despite of the attractive features of this approach, the nature of the non-Nernstian response of this system was not properly addressed. In this work, using a mixed potential model, the open circuit potential of the Pt electrode is shown to be under kinetic control of the oxygen reduction reaction (ORR). It is proposed that hydrogen peroxide acts as an oxygenated species that blocks free sites on the Pt surface, interfering with the ORR. Therefore, the effect of the polyelectrolyte coating can be understood in terms of the modulation of the factors that affects the kinetics of the ORR, such as an increase of the H+ concentration, minimization of the effect of the spectator species, etc. Because of the complexity and the lack of models that accurately describe systems with practical applications, this work is not intended to provide a mechanistic but rather a phenomenological view on problem. A general framework to understand the factors that affect the potentiometric response is provided. Experimental evidence showing that the use of polyelectrolyte coatings are a powerful way to control the mixed potential open new ways for the development of robust and simple potentiometric sensors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos Publication Date 2019-11-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2670; 1873-4324 ISBN Additional Links UA library record
  Impact Factor 6.2 Times cited Open Access
  Notes Approved Most recent IF: 6.2; 2020 IF: 4.95
  Call Number UA @ admin @ c:irua:184381 Serial 7731
Permanent link to this record
 

 
Author Eltayeb, M.A.H.; Van Grieken, R.E.
  Title Coprecipitation with aluminium hydroxide and x-ray fluorescence determination of trace metals in water Type A1 Journal article
  Year 1992 Publication Analytica chimica acta Abbreviated Journal
  Volume 268 Issue Pages 177-183
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1992JQ23300020 Publication Date 2002-07-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0003-2670; 1873-4324 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:2840 Serial 7733
Permanent link to this record
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