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	Author	Legrand, S.
	Title	Advanced chemical imaging of artworks			Type	Doctoral thesis
	Year	2021	Publication		Abbreviated Journal
	Volume		Issue		Pages	315 p.
	Keywords	Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Last century the field of heritage sciences expanded beyond imagination. The inventions of X-ray radiography and infrared reflectography allowed experts to investigate paintings below the surface as well. More recent developments led to the advent of the field of hyperspectral imaging, to which the advanced chemical imaging methods, used in this thesis work, belong. These techniques not only allow to identify the components present in artworks, but also to visualize their distribution over these objects. The resulting distribution maps permit a broader public to interpret the scientific data and to relate these results with the artwork itself. During this thesis work a range of flat artworks were investigated in a non-destructive manner using mainly two macroscopic imaging techniques: macroscopic X-ray fluorescence scanning and macroscopic Fourier transformed mid-infrared scanning in reflectance mode. The resulting images were sometimes supplemented with microscopic techniques on a minute selection of samples to fully understand the layer build-up, composition and distribution of these materials over the stratigraphy. Illuminated manuscripts pushed the interpretation of the macroscopic imaging techniques: due to the impossibility of sampling, all answers had to be obtained non-destructively. Documenting masterpieces such as the Ghent Altarpiece by means of chemical imaging techniques, helped the restoration team, assisted by the international commission to make the daring decision of manually removing the non-original paint layers. Scanning stained-glass windows allowed experts to document the panels, create situation reports, identify later infills and guide the restoration process in a more efficient manner. By initially applying non-destructive imaging techniques, many of the research/conservation questions could already be answered. Based on the resulting distribution maps, only a very limited amount of sampling was required to obtain a representative set to answer the remaining questions. In most cases the combination of multiple methods was necessary to fully understand the situation. A similar trend could be seen in the research field: the collaboration between divergent disciples was often required in order to explain all observations. In order to completely break through, the scanning speed of these techniques has to increase even more in order to cover an acceptable surface in one workday. Parallel with the operational speed, the (basic) data treatment should also be streamlined more in order to allow a broader user group to access the results. Once these two improvements are carried out, these techniques become accessible to a larger public.
	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		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:176342			Serial	7420
Permanent link to this record



	Author	Drăgan, A.-M.; Parrilla, M.; Feier, B.; Oprean, R.; Cristea, C.; De Wael, K.
	Title	Analytical techniques for the detection of amphetamine-type substances in different matrices : a comprehensive review			Type	A1 Journal article
	Year	2021	Publication	Trac-Trends In Analytical Chemistry	Abbreviated Journal	Trac-Trend Anal Chem
	Volume	145	Issue		Pages	116447
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	This current review focuses on contributions to amphetamine-type substances (ATS) analysis. This type of synthetic illicit drugs has been increasingly present worldwide reaching 5% of the market on illicit drugs in 2019. The increment of their production in many clandestine laboratories and easy distribution among society are two of the main concerns towards the battle against synthetic drugs. Therefore, the first part of this review details the classification and mechanism of action of ATS in the human body. Second, the pharmacological and toxicological effects of ATS on human health are described to motivate the need of early detection of ATS. Subsequently, the most used laboratory-based and portable methods are presented and critically discussed along the review. Finally, a careful discussion on the advantages and disadvantages of portable techniques employed on the field are addressed as potential tools for on-site ATS detection by law enforcement officers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000723747000009	Publication Date	2021-09-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0165-9936; 1879-3142	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.442	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 8.442
	Call Number	UA @ admin @ c:irua:183268			Serial	7460
Permanent link to this record



	Author	Daems, E.; Dewaele, D.; Barylyuk, K.; De Wael, K.; Sobott, F.
	Title	Aptamer-ligand recognition studied by native ion mobility-mass spectrometry			Type	A1 Journal article
	Year	2021	Publication	Talanta	Abbreviated Journal	Talanta
	Volume	224	Issue		Pages	121917
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The range of applications for aptamers, small oligonucleotide-based receptors binding to their targets with high specificity and affinity, has been steadily expanding. Our understanding of the mechanisms governing aptamer-ligand recognition and binding is however lagging, stymieing the progress in the rational design of new aptamers and optimization of the known ones. Here we demonstrate the capabilities and limitations of native ion mobility-mass spectrometry for the analysis of their higher-order structure and non-covalent interactions. A set of related cocaine-binding aptamers, displaying a range of folding properties and ligand binding affinities, was used as a case study in both positive and negative electrospray ionization modes. Using carefully controlled experimental conditions, we probed their conformational behavior and interactions with the high-affinity ligand quinine as a surrogate for cocaine. The ratios of bound and unbound aptamers in the mass spectra were used to rank them according to their apparent quinine-binding affinity, qualitatively matching the published ranking order. The arrival time differences between the free aptamer and aptamer-quinine complexes were consistent with a small ligand-induced conformational change, and found to inversely correlate with the affinity of binding. This mass spectrometry-based approach provides a fast and convenient way to study the molecular basis of aptamer-ligand recognition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000600787800122	Publication Date	2020-12-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0039-9140; 1873-3573	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.162	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.162
	Call Number	UA @ admin @ c:irua:174086			Serial	7490
Permanent link to this record



	Author	Stefan, G.; Hosu, O.; De Wael, K.; Jesus Lobo-Castanon, M.; Cristea, C.
	Title	Aptamers in biomedicine : selection strategies and recent advances			Type	A1 Journal article
	Year	2021	Publication	Electrochimica Acta	Abbreviated Journal	Electrochim Acta
	Volume	376	Issue		Pages	137994
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Aptamers have come in the spotlight as bio-mimetic molecular recognition elements in the field of biomedicine due to various applications in diagnostics, drug delivery, therapeutics, and pharmaceutical analysis. Aptamers are composed of nucleic acid strands (DNA or RNA) that can specifically interact in a three-dimensional tailored design with the target molecule. The basic method to generate aptamers is Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Recent technological advances in aptamer selection allow for faster and cheaper production of a new generation of high-affinity aptamers compared to the traditional SELEX, which can last up to several months. Rigorous characterization performed by multiple research groups endorsed several well-defined aptamer sequences. Binding affinity, nature of the biomolecular interactions and structural characterization are of paramount importance for aptamer screening and development of applications. However, remarkable challenges still need to be dealt with before the aptamers can make great contributions to the biomedical field. Poor specificity and sensitivity, questionable clinical use, low drug loading, in vivo stability and toxicity are only some of the identified challenges. This review accounts for the 30th celebration of the SELEX technology underlining the most important aptamers' achievements in the biomedical field within mostly the past five years. Aptamers' advantages over antibodies are discussed. Because of potential clinical translational utility, insights of remarkable developments in aptamer-based methods for diagnosis and monitoring of disease biomarkers and pharmaceuticals are discussed focusing on the recent studies (2015-2020). The current challenges and promising opportunities for aptamers for therapeutic and theragnostic purposes are also presented. (C) 2021 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000634761900003	Publication Date	2021-02-22
	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:177677			Serial	7491
Permanent link to this record



	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	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	Fuoco, T.; Cuartero, M.; Parrilla, M.; García-Guzmán, J.J.; Crespo, G.A.; Finne-Wistrand, A.
	Title	Capturing the real-time hydrolytic degradation of a library of biomedical polymers by combining traditional assessment and electrochemical sensors			Type	A1 Journal article
	Year	2021	Publication	Biomacromolecules	Abbreviated Journal	Biomacromolecules
	Volume	22	Issue	2	Pages	949-960
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	We have developed an innovative methodology to overcome the lack of techniques for real-time assessment of degradable biomedical polymers at physiological conditions. The methodology was established by combining polymer characterization techniques with electrochemical sensors. The in vitro hydrolytic degradation of a series of aliphatic polyesters was evaluated by following the molar mass decrease and the mass loss at different incubation times while tracing pH and l-lactate released into the incubation media with customized miniaturized electrochemical sensors. The combination of different analytical approaches provided new insights into the mechanistic and kinetics aspects of the degradation of these biomedical materials. Although molar mass had to reach threshold values for soluble oligomers to be formed and specimens’ resorption to occur, the pH variation and l-lactate concentration were direct evidence of the resorption of the polymers and indicative of the extent of chain scission. Linear models were found for pH and released l-lactate as a function of mass loss for the l-lactide-based copolymers. The methodology should enable the sequential screening of degradable polymers at physiological conditions and has potential to be used for preclinical material’s evaluation aiming at reducing animal tests.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-01-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1525-7797	ISBN		Additional Links	UA library record
	Impact Factor	5.246	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 5.246
	Call Number	UA @ admin @ c:irua:175296			Serial	7575
Permanent link to this record



	Author	Sleegers, N.
	Title	Cephalosporin antibiotics : electrochemical fingerprints and redox pathways investigated by mass spectral analysis			Type	Doctoral thesis
	Year	2021	Publication		Abbreviated Journal
	Volume		Issue		Pages	208 p.
	Keywords	Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	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		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:181014			Serial	7588
Permanent link to this record



	Author	Alemam, E.
	Title	Cleaning of wall paintings by Polyvinyl alcohol–Borax/Agarose (PVA–B/AG) double network hydrogels : characterization, assessment, and applications			Type	Doctoral thesis
	Year	2021	Publication		Abbreviated Journal
	Volume		Issue		Pages	184 p.
	Keywords	Doctoral thesis; Engineering sciences. Technology; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Wall paintings make up an important section of cultural heritage. They resemble time portals that can be used to travel back into the past and witness the life of our ancestors. In these paintings, the ancient artists depicted the different aspects of their life, such as cooking, baking, farming, manufacturing, as well as thoughts and beliefs. Unfortunately, wall paintings are susceptible to degradation over time in the form of the accumulations of dirt and deposits on the painted surfaces and loss of adhesion of the paint layers at the surface. Therefore, the removal of these deposits is one of the primary duties of conservator-restorers. Such operations are intended to restore the painted surface to a condition close enough to its original state. Since cleaning artworks may cause undesirable physicochemical alterations and is nonreversible, the proper cleaning procedure should be adopted. In this regard, numerous gels have been developed and exploited for the cleaning of various artwork surfaces. Lately, polyvinyl alcohol-borax (PVA-B) and agarose (AG) hydrogels have been widely employed as cleaning materials by conservator-restorers. However, both hydrogels have shown limitations in specific cleaning practices. In this work, we investigated a new double network hydrogel based on blending PVA-B and agarose to avoid the limitations posed by the constituting hydrogels. For this reason, a detailed characterization of the PVA–B/AG double network hydrogel was performed, including chemical structure, liquid phase retention, mechanical strength, rheological behavior, and self-healing behavior of various PVA-B/AG hydrogels. These new hydrogels revealed better properties than PVA-B and agarose hydrogels and obviated their limitations. A laboratory experiment on the removal of deteriorated Paraloid® B72 proved that the PVA-B/AG hydrogel loaded 10%/10% MEK/1-PeOH was able to remove these layers efficiently. Therefore, the hydrogel was tested on a wall painting from the Temple of Seti I in Abydos – Egypt. It removed the glossy/darkened consolidant from the wall painting and restored the original matt appearance of the painted surface. In another application on the painted ceiling of the same temple, the hydrogel was tested for removing thick soot layers. The hydrogel formulation (loaded with 5% ammonia, 0.3% ammonium carbonate, and 0.3% EDTA) removed these layers with no noticeable damage to the paint layers. In a wide-scale application of the hydrogel (loaded with 10% propylene carbonate), it removed a highly deteriorated varnish layer from a 19-c wall painting. All the traditional cleaning methods employed caused damage to the paint layers, proving that gel cleaning can be a safer cleaning alternative in some cases.
	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		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:183381			Serial	7671
Permanent link to this record



	Author	Puglisi, A.; Bassini, S.; Reimhult, E.
	Title	Cyclodextrin-appended superparamagnetic iron oxide nanoparticles as cholesterol-mopping agents			Type	A1 Journal article
	Year	2021	Publication	Frontiers In Chemistry	Abbreviated Journal	Front Chem
	Volume	9	Issue		Pages	795598
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Cholesterol plays a crucial role in major cardiovascular and neurodegenerative diseases, including Alzheimer’s disease and rare genetic disorders showing altered cholesterol metabolism. Cyclodextrins (CDs) have shown promising therapeutic efficacy based on their capacity to sequester and mobilise cholesterol. However, the administration of monomeric CDs suffers from several drawbacks due to their lack of specificity and poor pharmacokinetics. We present core-shell superparamagnetic iron oxide nanoparticles (SPIONs) functionalised with CDs appended to poly (2-methyl-2-oxazoline) polymers grafted in a dense brush to the iron oxide core. The CD-decorated nanoparticles (CySPIONs) are designed so that the macrocycle is specifically cleaved off the nanoparticle’s shell at a slightly acidic pH. In the intended use, free monomeric CDs will then mobilise cholesterol out of the lysosome to the cytosol and beyond through the formation of an inclusion complex. Hence, its suitability as a therapeutic platform to remove cholesterol in the lysosomal compartment. Synthesis and full characterization of the polymer as well as of the core-shell SPION are presented. Cholesterol-binding activity is shown through an enzymatic assay.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-11-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2296-2646	ISBN		Additional Links	UA library record
	Impact Factor	3.994	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 3.994
	Call Number	UA @ admin @ c:irua:192273			Serial	7749
Permanent link to this record



	Author	Parrilla, M.; Montiel, F.N.; Van Durme, F.; De Wael, K.
	Title	Derivatization of amphetamine to allow its electrochemical detection in illicit drug seizures			Type	A1 Journal article
	Year	2021	Publication	Sensors And Actuators B-Chemical	Abbreviated Journal	Sensor Actuat B-Chem
	Volume	337	Issue		Pages	129819
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Amphetamine (AMP) is posing critical issues in our society being one of the most encountered drugs-of-abuse in the current illicit market. The continuous drug production in Europe urges the development of new tools for the rapid on-site determination of illicit drugs such as AMP. However, the direct electrochemical detection of AMP is a challenge because the molecule is non-electroactive at the potential window of conventional graphite SPEs. For this reason, a derivatization step is needed to convert the primary amine into an electroactive oxidizable group. Herein, the rapid electrochemical detection of AMP in seized samples based on the derivatization by 1,2-naphthoquinone-4-sulfonate (NQS) is presented by using square wave voltammetry (SWV) at graphite screen-printed electrodes (SPEs). First, a detailed optimization of the key parameters and the analytical performance is provided. The method showed a sensitivity of 7.9 µA mM-1 within a linear range from 50 to 500 µM, a limit of detection of 22.2 µM, and excellent reproducibility (RSD = 4.3%, n = 5 at 500 µM). Subsequently, the effect of NQS on common cutting agents for the selective detection of AMP is addressed. The comparison of the method with drugs-of-abuse containing secondary and tertiary amines confirms the selectivity of the method. Finally, the concept is applied to quantify AMP in 20 seized samples provided by forensic laboratories, exhibiting an accuracy of 97.3 ± 10.5%. Overall, the fast analysis of samples with the electrochemical profiling of derivatized AMP exhibits a straightforward on-site screening aiming to facilitate the tasks of law enforcement agents in the field.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000640386500001	Publication Date	2021-03-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-4005	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.401	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 5.401
	Call Number	UA @ admin @ c:irua:176353			Serial	7762
Permanent link to this record



	Author	Blidar, A.-M.
	Title	The development of sensitive and selective electrochemical methods for the detection of antibiotics			Type	Doctoral thesis
	Year	2021	Publication		Abbreviated Journal
	Volume		Issue		Pages	139 p.
	Keywords	Doctoral thesis; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	The discovery of antibiotics represented one of the greatest breakthroughs in medicine. Their success combined with an increasing intensive use is apparently bound to be also their undoing. This is due to the development of acquired antibiotic resistance, leading to inefficient antibiotherapy and even to the impossibility of treatment and death. The development and spread of antibiotic resistance are fueled by the widespread presence of trace levels of antibiotics residue, in various media, from environment to aliments. One of the solutions is the rigorous monitoring of the levels of antibiotics, which in term requires an almost constant development of new, more accessible analytical methods, especially screening methods, capable of decentralized analysis. In this direction, the electrochemical detection of antibiotics represents a very viable alternative. In this context, the aim of this thesis was to develop new electrochemical methods for the detection of antibiotics by employing and expanding on several strategies, like biomimetic sensors and electrochemical fingerprinting. Five studies were described in this thesis, that can be roughly divided in three categories, based on the analytical strategy employed. The first group is represented by direct electrochemical methods. The second group focuses on the use of biomimetic elements, molecularly imprinted polymers and aptamers. The hyphenation of electrochemical methods with other analytical methods was explored in the last group. In the last study, included in this group, the singlet oxygen-based photoelectrochemical approach was used for the detection of a phenolic antibiotic, rifampicin. The originality of the thesis consists in the testing and development of new approaches to various strategies used in electrochemical detection, revealing new insights in the field of electrochemical detection of antibiotics. The complex electrochemical fingerprint and the mechanism of the electrochemical oxidation were created and investigated, respectively, for the antibiotic vancomycin. New sensitive nanoplatforms were prepared by employing and combining new protocols. Additionally, important contributions were brought through the study involving the singlet oxygen-based detection of rifampicin. We demonstrated how a photocatalyst can exhibit analyte selectivity by strongly interacting with a complex phenolic compound, rifampicin. Summing up, the studies presented in this thesis will have an important impact in the field of electrochemical detection of antibiotics.
	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		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:182955			Serial	7804
Permanent link to this record



	Author	Muhammad, S.; Wuyts, K.; De Wael, K.; Samson, R.
	Title	Does leaf micro-morphology influence the recognition of particles on SEM images?			Type	A3 Journal article
	Year	2021	Publication	International Journal of Environmental Pollution and Remediation	Abbreviated Journal
	Volume	9	Issue		Pages	22-37
	Keywords	A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Scanning electron microscopy (SEM) remains a popular approach to determine the shape, size, density and elemental composition of particles collected on leaf surfaces, but the effect of leaf micro-morphology on particle counts is not very well known. In this study, leaves of sixteen urban plant species were examined for particle density in June and September 2016 using SEM. The investigated plant species differed in leaf micro-morphology involving trichomes, raised stomata, epicuticular wax crystals and convex epidermal cells forming deep grooves between cells. The particle density on leaves of the investigated plant species was estimated by particle size fraction and leaf side. Particle density was significantly higher on the adaxial (AD) leaf side compared to the abaxial (AB) leaf side and higher for fine-particles than coarse-particles. The effect of trichome density on particle density of the AB and the AD leaf side was indicated to be significant and positive for both coarse and fine-particles in June but not in September. The successive repeated measurements elucidated that features constructing the topography of a leaf surface such as trichomes, stomata, and epidermal cells frequently contributed towards the edge enhancement effect, resulting in exaggerated particle counts. Besides, the mechanical drift contributed to the disparity in particle density measurements. Lastly, the reduction in particle density between successive measurements were imputed on the charging effect. These results enable us to suggest that in addition to characterization of micro-morphological features on a leaf surface, SEM will continue to be a useful approach for determining the particle: shape, size, elemental composition and density of the deposited particles. Nonetheless, the disparity in particle density measurements can occur due to abnormal particle recognition. Based on the results of September, we recommend that within-session successive repeated measurements (~ n ≥ 5) need to be performed to remove measurement uncertainties and obtain reliable quantitative data of particle counts using SEM.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-09-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:181797			Serial	7822
Permanent link to this record



	Author	Mirbagheri, N.; Campos, R.; Ferapontova, E.E.
	Title	Electrocatalytic oxidation of water by OH^- – and H₂O-capped IrO_x nanoparticles electrophoretically deposited on graphite and basal plane HOPG : effect of the substrate electrode			Type	A1 Journal article
	Year	2021	Publication	Chemelectrochem	Abbreviated Journal	Chemelectrochem
	Volume	8	Issue	9	Pages	1632-1641
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Iridium oxide (IrOx) is one of the most efficient electrocatalysts for water oxidation reaction (WOR). Here, WOR electrocatalysis by 1.6 nm IrOx nanoparticles (NPs) electrophoretically deposited onto spectroscopic graphite (Gr) and basal plane highly ordered pyrolytic graphite (HOPG) was studied as a function of NPs' capping ligands and electrodeposition substrate. On Gr, OH-- and H2O-capped NPs exhibited close sub-monolayer surface coverages and specific electrocatalytic activity of 18.9-23.5 mA nmol(-1) of Ir-IV/V sites, at 1 V and pH 7. On HOPG, OH--capped NPs produced films with a diminished WOR activity of 5.17 +/- 2.40 mA nmol(-1). Electro-wettability-induced changes impeded electrophoretic deposition of H2O-capped NPs on HOPG, WOR currents being 25-fold lower than observed for OH--capped ones. The electrocatalysis efficiency correlated with hydrophilic properties of the substrate electrodes, affecting morphological and as a result catalytic properties of the formed IrOx films. These results, important both for studied and related carbon nanomaterials systems, allow fine-tuning of electrocatalysis by a proper choice of the substrate electrode.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000664219100012	Publication Date	2021-04-16
	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:179719			Serial	7859
Permanent link to this record



	Author	Moiseeva, E.O.; Trashin, S.; Korostei, Y.S.; Khan, S.U.; Kosov, A.D.; De Wael, K.; Dubinina, T.V.; Tomilova, L.G.
	Title	Electrochemical and spectroelectrochemical studies of tert-butyl-substituted aluminum phthalocyanine			Type	A1 Journal article
	Year	2021	Publication	Polyhedron	Abbreviated Journal	Polyhedron
	Volume	200	Issue		Pages	115136
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Tetra-tert-butylphthalocyanine aluminum (III) chloride was studied by voltammetric and potential-resolved spectroelectrochemical methods in a non-coordinating solvent o-dichlorobenzene. Five redox transitions were found including two oxidation waves at 0.18 and 0.90 V and three reduction waves at −1.28, −1.65, and −2.63 V vs. Fc+/Fc. Electrochemical reversibility of the first oxidation and reduction processes was assessed by using the diagnostic criteria of cyclic voltammetry. First comprehensive spectroelectrochemical characterization of oxidation of the aluminum phthalocyanine is reported. Moreover, potential-resolved spectroelectrochemical titration revealed strong influence of aggregation on the UV–vis spectra and the half-wave potentials of the first oxidation transition and disclosed the presence of the partially oxidized complex in the initial solution, which noticeably affected the spectrum of the neutral form.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000640386000006	Publication Date	2021-03-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0277-5387	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.926	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 1.926
	Call Number	UA @ admin @ c:irua:176389			Serial	7860
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	Author	Dragan, A.-M.; Truta, F.M.; Tertis, M.; Florea, A.; Schram, J.; Cernat, A.; Feier, B.; De Wael, K.; Cristea, C.; Oprean, R.
	Title	Electrochemical fingerprints of illicit drugs on graphene and multi-walled carbon nanotubes			Type	A1 Journal article
	Year	2021	Publication	Frontiers In Chemistry	Abbreviated Journal	Front Chem
	Volume	9	Issue		Pages	641147
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Illicit drugs use and abuse remains an increasing challenge for worldwide authorities and, therefore, it is important to have accurate methods to detect them in seized samples, biological fluids and wastewaters. They are recently classified as the latest group of emerging pollutants as their consumption increased tremendously in recent years. Nanomaterials have gained much attention over the last decade in the development of sensors for a myriad of applications. The applicability of these nanomaterials, functionalized or not, significantly increases and it is therefore highly suitable for use in the detection of illicit drugs. We have assessed the suitability of various nanoplatforms, such as graphene (GPH), multi-walled carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) for the electrochemical detection of illicit drugs. GPH and MWCNTs were chosen as the most suitable platforms and cocaine, 3,4-methylendioxymethamfetamine (MDMA), 3-methylmethcathinone (MMC) and alpha-pyrrolidinovalerophenone (PVP) were tested. Due to the hydrophobicity of the nanomaterials-based platforms which led to low signals, two strategies were followed namely, pretreatment of the electrodes in sulfuric acid by cyclic voltammetry and addition of Tween 20 to the detection buffer. Both strategies led to an increase in the oxidation signal of illicit drugs. Binary mixtures of illicit drugs with common adulterants found in street samples were also investigated. The proposed strategies allowed the sensitive detection of illicit drugs in the presence of most adulterants. The suitability of the proposed sensors for the detection of illicit drugs in spiked wastewaters was finally assessed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000634708900001	Publication Date	2021-03-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2296-2646	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.994	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.994
	Call Number	UA @ admin @ c:irua:177704			Serial	7861
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	Author	Schram, J.; Parrilla, M.; Sleegers, N.; Van Durme, F.; van den Berg, J.; van Nuijs, A.L.N.; De Wael, K.
	Title	Electrochemical profiling and liquid chromatography–mass spectrometry characterization of synthetic cathinones : from methodology to detection in forensic samples			Type	A1 Journal article
	Year	2021	Publication	Drug Testing And Analysis	Abbreviated Journal	Drug Test Anal
	Volume	13	Issue	7	Pages	1282-1294
	Keywords	A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	The emergence of new psychoactive drugs in the market demands rapid and accurate tools for the on‐site classification of illegal and legal compounds with similar structures. Herein, a novel method for the classification of synthetic cathinones (SC) is presented based on their electrochemical profile. First, the electrochemical profile of five common SC (i.e., mephedrone, ethcathinone, methylone, butylone and 4‐chloro‐alpha‐pyrrolidinovalerophenone) is collected to build calibration curves using square wave voltammetry on graphite screen‐printed electrodes (SPE). Second, the elucidation of the oxidation pathways, obtained by liquid chromatography‐high resolution mass spectrometry, allows the pairing of the oxidation products to the SC electrochemical profile, providing a selective and robust classification. Additionally, the effect of common adulterants and illicit drugs on the electrochemical profile of the SC is explored. Interestingly, a cathodic pretreatment of the SPE allows the selective detection of each SC in presence of electroactive adulterants. Finally, the electrochemical approach is validated with gas‐chromatography‐mass spectrometry by analyzing 26 confiscated samples from seizures and illegal webshops. Overall, the electrochemical method exhibits a successful classification of SC including structural derivatives, a crucial attribute in an ever‐diversifying drug market.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000624902500001	Publication Date	2021-02-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1942-7603; 1942-7611	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.469	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.469
	Call Number	UA @ admin @ c:irua:175583			Serial	7863
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	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	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	Parrilla, M.; Joosten, F.; De Wael, K.
	Title	Enhanced electrochemical detection of illicit drugs in oral fluid by the use of surfactant-mediated solution			Type	A1 Journal article
	Year	2021	Publication	Sensors And Actuators B-Chemical	Abbreviated Journal	Sensor Actuat B-Chem
	Volume	348	Issue		Pages	130659
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Illicit drug consumption is a worldwide worrying phenomenon that troubles modern society. For this reason, law enforcement agencies (LEAs) are placing tremendous efforts into tackling the spreading of such substances among our community. New sensing technologies can facilitate the LEAs duties by providing portable and affordable analytical devices. Herein, we present for the first time a sensitive and low-cost electrochemical method, i.e. square-wave adsorptive stripping voltammetry on carbon screen-printed electrodes (SPE), for the detection of five illicit drugs (i.e. cocaine, heroin, 3,4-methylenedioxymethamphetamine, 4-chloro-alpha-pyrrolidinovalerophenone, and ketamine) in oral fluid by the aid of a surfactant. Particularly, the surfactant is adsorbed at the carbon electrode’s surface and yields the adsorption of illicit drug molecules, allowing for an enhanced electrochemical signal in comparison to surfactant-free media. First, the surfactant-mediated behavior is deeply explored at the SPE by cyclic voltammetry, electrochemical impedance spectroscopy, and Fourier-transform infrared spectroscopy. Subsequently, the electrochemical behavior of the five illicit drugs is studied and optimized to render optimal analytical performance. Accordingly, the analytical system exhibited a wide linear concentration range from 1 to 30 µM with sub-micromolar limits of detection and high sensitivity. This performance is similar to other reported electrochemical sensors, but with the advantage of using an unmodified SPE, thus avoiding costly and complex functionalization of the SPE. Finally, the methodology was evaluated in diluted oral fluid samples spiked with illicit drugs. Overall, this work describes a simple, rapid, portable, and sensitive method for the detection of illicit drugs aiming to provide oral fluid testing opportunities to LEAs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000701915600005	Publication Date	2021-08-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-4005	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.401	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 5.401
	Call Number	UA @ admin @ c:irua:181307			Serial	7912
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	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	Gomes, N.O.; Mendonça, C.D.; Machado, S.A.S.; Oliveira, O.N., Jr.; Raymundo-Pereira, P.A.
	Title	Flexible and integrated dual carbon sensor for multiplexed detection of nonylphenol and paroxetine in tap water samples			Type	A1 Journal article
	Year	2021	Publication	Microchimica Acta	Abbreviated Journal	Microchim Acta
	Volume	188	Issue	10	Pages	359
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Multiplex detection of emerging pollutants is essential to improve quality control of water treatment plants, which requires portable systems capable of real-time monitoring. In this paper we describe a flexible, dual electrochemical sensing device that detects nonylphenol and paroxetine in tap water samples. The platform contains two voltammetric sensors, with different working electrodes that were either pretreated or functionalized. Each working electrode was judiciously tailored to cover the concentration range of interest for nonylphenol and paroxetine, and square wave voltammetry was used for detection. An electrochemical pretreatment with sulfuric acid on the printed electrode enabled a selective detection of nonylphenol in 1.0-10 x 10(-6) mol L-1 range with a limit of detection of 8.0 x 10(-7) mol L-1. Paroxetine was detected in the same range with a limit of detection of 6.7 x 10(-7) mol L-1 using the printed electrode coated with a layer of carbon spherical shells. Simultaneous detection of the two analytes was achieved in tap water samples within 1 min, with no fouling and no interference effects. The long-term monitoring capability of the dual sensor was demonstrated in phosphate buffer for 45 days. This performance is statistically equivalent to that of high-performance liquid chromatography (HPLC) for water analysis. The dual-sensor platform is generic and may be extended to other water pollutants and clinical biomarkers in real-time monitoring of the environment and health conditions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000702722700001	Publication Date	2021-10-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0026-3672; 1436-5073	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.58	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 4.58
	Call Number	UA @ admin @ c:irua:182649			Serial	7973
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	Author	Van Hal, M.; Campos, R.; Lenaerts, S.; De Wael, K.; Verbruggen, S.W.
	Title	Gas phase photofuel cell consisting of WO₃- and TiO₂-photoanodes and an air-exposed cathode for simultaneous air purification and electricity generation			Type	A1 Journal article
	Year	2021	Publication	Applied Catalysis B-Environmental	Abbreviated Journal	Appl Catal B-Environ
	Volume	292	Issue		Pages	120204
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Research has shown the potential of photofuel cells (PFCs) for waste water treatment, enabling the (partial) recovery of the energy released from the degraded compounds as electricity. Literature on PFCs targeting air pollution on the other hand is extremely scarce. In this work an autonomously operating air purification device targeting sustainable electricity generation is presented. Knowledge on gas phase operation of PFCs was gathered by combining photocatalytic and photoelectrochemical measurements, both for TiO2 and WO3-based photocatalysts. While TiO2-based photocatalysts performed better in direct photocatalytic experiments, they were outperformed by WO3-based photoanodes in all-gas-phase PFC operation. Not only do WO3-based photocatalysts generate the highest steady state photocurrent, they also achieved the highest fuel-to-electricity conversion (>65 %). The discrepancies between gas phase photocatalytic and photoelectrochemical processes highlight the difference in driving material properties. This study serves as a proof-of-concept towards development of an autonomous, low-cost and widely applicable waste gas-to-electricity PFC device.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000663216500001	Publication Date	2021-04-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0926-3373	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.446	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 9.446
	Call Number	UA @ admin @ c:irua:177075			Serial	7989
Permanent link to this record



	Author	Beltran, V.; Marchetti, A.; De Meyer, S.; Nuyts, G.; De Wael, K.
	Title	Geranium lake pigments : the role of the synthesis on the structure and composition			Type	A1 Journal article
	Year	2021	Publication	Dyes And Pigments	Abbreviated Journal	Dyes Pigments
	Volume	189	Issue		Pages	109260
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Eosin Y has an extraordinary capacity to form complexes with metallic elements, that have applications in many different fields, from photovoltaics and photocatalysis to historical artists? pigments. To unravel the complexes reactivity, it is essential to have a precise knowledge of their structure and composition, as well as how these can be affected by the synthesis protocol, an often underestimated factor. This manuscript presents a thorough investigation of the structure and composition of eosin Y complexes based on Al and Pb, by FTIR, XRPD and Raman spectroscopy, with a particular focus on the effect of the synthesis conditions. Results clearly show the change of the coordination mode in Pb complexes depending on the protocol, while the structure of Al complexes remains stable. In both cases, the formation of by-products was observed. Additionally, a detailed band assignment of the FTIR and Raman spectra of eosin Y and Pb and Al complexes is described, providing interesting details such as the interaction between the metallic ion and the xanthene moiety (chromophore). This is extremely important for the analysis of historical paintings where eosin Y is bonded to metallic ions, as well as for other materials in dye-sensitized solar cells, wastewater treatment or photocatalysis.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000634733200001	Publication Date	2021-03-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0143-7208	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.473	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.473
	Call Number	UA @ admin @ c:irua:177676			Serial	8002
Permanent link to this record



	Author	Alvarez-Martin, A.; Newsome, G.A.; Janssens, K.
	Title	High-resolution mass spectrometry and nontraditional mass defect analysis of brominated historical pigments			Type	A1 Journal article
	Year	2021	Publication	Analytical Chemistry	Abbreviated Journal	Anal Chem
	Volume	93	Issue	44	Pages	14851-14858
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	The implementation of high-resolution mass spectrometry systems offers new possibilities for the analysis of complex art samples such as historical oil paintings. However, these multicomponent systems generate large and complex data sets that require advanced visualization tools to aid interpretation, especially when no chromatographic separation is performed. In the context of this research, it was crucial to propose a data analysis tool to identify the products generated during the synthesis, drying, and aging of historical pigments. This study reports for the first time a nontraditional mass defect analysis of oil paint samples containing a fugitive brominated-organic pigment, eosin or geranium lake, by using direct infusion electrospray ionization in combination with a high-resolution Orbitrap mass spectrometer. The use of nontraditional Kendrick mass defect plots is presented in this study as a processing and visualization tool to recognize brominated species based on their specific mass defect and isotope pattern. The results demonstrate that this approach could provide valuable molecular compositional information on the degradation pathways of this pigment. We anticipate that mass defect analysis will become highly relevant in future degradation studies of many more historical organic pigments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000718171600037	Publication Date	2021-10-29
	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	OpenAccess
	Notes				Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:182347			Serial	8038
Permanent link to this record



	Author	Aucar Boidi, N.; Fernández García, H.; Nunez-Fernandez, Y.; Hallberg, K.
	Title	In-gap band in the one-dimensional two-orbital Kanamori-Hubbard model with interorbital Coulomb interaction			Type	A1 Journal article
	Year	2021	Publication	Physical review research	Abbreviated Journal
	Volume	3	Issue	4	Pages	043213
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	We study the electronic spectral properties at zero temperature of the one-dimensional (1D) version of the degenerate two-orbital Kanamori-Hubbard model, one of the well-established frameworks to study transition metal compounds, using state-of-the-art numerical techniques based on the density matrix renormalization group. While the system is Mott insulating for the half-filled case, as expected for an interacting 1D system, we find interesting and rich structures in the single-particle density of states (DOS) for the hole-doped system. In particular, we find the existence of in-gap states which are pulled down to lower energies from the upper Hubbard band with increasing the interorbital Coulomb interaction V. We analyze the composition of the DOS by projecting it onto different local excitations, and we observe that for large dopings these in-gap excitations are formed mainly by interorbital holon-doublon (HD) states and their energies follow approximately the HD states in the atomic limit. We observe that the Hund interaction J increases the width of the in-gap band, as expected from the two-particle fluctuations in the Hamiltonian. The observation of a finite density of states within the gap between the Hubbard bands for this extended 1D model indicates that these systems present a rich excitation spectra which could help us understand the microscopic physics behind multiorbital compounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000736651500002	Publication Date	2021-12-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:184836			Serial	8073
Permanent link to this record



	Author	Alvarez-Martin, A.; Wilcop, M.; Anderson, R.; Wendt, D.; Barden, R.; Kavich, G.M.
	Title	Investigation of volatile organic compounds in museum storage areas			Type	A1 Journal article
	Year	2021	Publication	Air Quality Atmosphere And Health	Abbreviated Journal	Air Qual Atmos Hlth
	Volume	14	Issue	11	Pages	1797-1809
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	This study investigates the complex mixture of volatile organic compounds (VOCs) released by and accumulated within a collection of historic medicinal, pharmaceutical, and cosmetic artifacts housed at the National Museum of American History (Smithsonian Institution). In recent years, staff have become concerned, both for the safety of the objects and for personnel working in the collection, about strong unremediated odors accumulating within several storage cabinets. Museum staff also wondered if non-odorous off-gassing might need remediation. Solid-phase microextraction combined with gas chromatography–mass spectrometry analysis (SPME–GC–MS) was used to identify VOCs present in the storage room housing the collection. Over 160 compounds were detected and identified overall. Among these, 49 appeared to be directly related to ingredients used in the manufacture of many collection items. The results of the study suggest that SPME–GC–MS can be a strong tool for the rapid screening of multicomponent museum collections exhibiting off-gassing problems, before the pursuit of other more tedious analytical approaches. Additionally, the study reveals valuable insight into the characteristic volatile emission of historic medicinal, pharmaceutical, and cosmetic artifacts, increasing understanding of, and decision-making for, similar collections of objects. Eventually, it is hoped that this information can be used to inform mitigation strategies for the capture and reduction of VOCs in collections storage areas.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000659058300001	Publication Date	2021-06-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1873-9318	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.184	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 3.184
	Call Number	UA @ admin @ c:irua:181923			Serial	8129
Permanent link to this record



	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	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
Permanent link to this record



	Author	Daems, E.; Moro, G.; Campos, R.; De Wael, K.
	Title	Mapping the gaps in chemical analysis for the characterisation of aptamer-target interactions			Type	A1 Journal article
	Year	2021	Publication	Trac-Trends In Analytical Chemistry	Abbreviated Journal	Trac-Trend Anal Chem
	Volume	142	Issue		Pages	116311
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Aptamers are promising biorecognition elements with a wide applicability from therapeutics to bio-sensing. However, to successfully use these biomolecules, a complete characterisation of their bindingperformance in the presence of the target is crucial. Several multi-analytical approaches have been re-ported including techniques to describe kinetic and thermodynamic aspects of the aptamer-targetinteraction, and techniques which allow an in-depth understanding of the aptamer-target structures.Recent literature shows the need of a critical data interpretation, a combination of characterisationtechniques and suggests the key role of the characterisation protocol design. Indeed, thefinal applicationof the aptamer should be considered before choosing the characterisation method. All the limitations andcapabilities of the analytical tools in use for aptamer characterisation should be taken into account. Here,we present a critical overview of the current methods and multi-analytical approaches to study aptamer-target binding, aiming to provide researchers with guidelines for the design of characterisation protocols.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000682179000010	Publication Date	2021-04-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0165-9936; 1879-3142	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.442	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 8.442
	Call Number	UA @ admin @ c:irua:179407			Serial	8203
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	Author	Baly, L.; Quesada, I.; Murray, A.S.; Martin, G.; van Espen, P.; Arteche, R.; Jain, M.
	Title	Modeling the charge deposition in quartz grains during natural irradiation and its influence on the optically stimulated luminescence signal			Type	A1 Journal article
	Year	2021	Publication	Radiation Measurements	Abbreviated Journal	Radiat Meas
	Volume	142	Issue		Pages	106564
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The rate of charge deposition in quartz grains irradiated in natural conditions is computed by radiation transport modeling. Quartz luminescence models are modified with the addition of the resulting charge deposition term, and the influence of this process on the optically stimulated luminescence (OSL) signal is analyzed. The results indicate that the charge deposition occurring in the quartz grain during the time of residence within rock could lead to the depletion of trapped holes in the recombination centres. For the two different quartz models investigated here, complete depletion is expected to occur for rock ages between 500 Ma and 1100 Ma. It is predicted that for sedimentary quartz derived from such rocks, the OSL signal is dominated by the slow component. It was also found that the shape and saturation level of the natural sensitivity-corrected dose response curve (DRC) of quartz is affected by the charge deposition; specifically, a linear reduction of the saturation level with the age of the rock is observed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000639160300003	Publication Date	2021-03-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1350-4487	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.442	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 1.442
	Call Number	UA @ admin @ c:irua:178307			Serial	8265
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	Author	Castanheiro, A.; Wuyts, K.; Hofman, J.; Nuyts, G.; De Wael, K.; Samson, R.
	Title	Morphological and elemental characterization of leaf-deposited particulate matter from different source types : a microscopic investigation			Type	A1 Journal article
	Year	2021	Publication	Environmental Science And Pollution Research	Abbreviated Journal	Environ Sci Pollut R
	Volume	28	Issue	20	Pages	25716-25732
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Particulate matter (PM) deposition on urban green enables the collection of particulate pollution from a diversity of contexts, and insight into the physico-chemical profiles of PM is key for identifying main polluting sources. This study reports on the morphological and elemental characterization of PM2-10 deposited on ivy leaves from five different environments (forest, rural, roadside, train, industry) in the region of Antwerp, Belgium. Ca. 40,000 leaf-deposited particles were thoroughly investigated by particle-based analysis using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX) and their physico-chemical characteristics were explored for PM source apportionment purposes. The size distribution of all deposited particles was biased towards small-sized PM, with 32% of the particles smaller than 2.5 mu m (PM2.5) and median diameters of 2.80-3.09 mu m. The source type influenced both the particles' size and morphology (aspect ratio and shape), with roadside particles being overall the smallest in size and the most spherical. While forest and rural elemental profiles were associated with natural PM, the industry particles revealed the highest anthropogenic metal input. PM2-10 profiles for roadside and train sites were rather comparable and only distinguishable when evaluating the fine (2-2.5 mu m) and coarse (2.5-10 mu m) PM fractions separately, which enabled the identification of a larger contribution of combustion-derived particles (small, circular, Fe-enriched) at the roadside compared to the train. Random forest prediction model classified the source type correctly for 61-85% of the leaf-deposited PM. The still modest classification accuracy denotes the influence of regional background PM and demands for additional fingerprinting techniques to facilitate source apportionment. Nonetheless, the obtained results demonstrate the utility of leaf particle-based analysis to fingerprint and pinpoint source-specific PM, particularly when considering both the composition and size of leaf-deposited particles.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000609067300006	Publication Date	2021-01-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0944-1344; 1614-7499	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.741	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 2.741
	Call Number	UA @ admin @ c:irua:176082			Serial	8282
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	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.
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	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	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
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