| |
Records |
Links  |
|
Author |
Dubinina, T.; Maklakov, S.; Petrusevich, E.; Borisova, N.E.; Trashin, S.A.; De Wael, K.; Tomilova, L.G. |
|
| |
Title |
Photoactive layers for photovoltaics based on near-infrared absorbing aryl-substituted naphthalocyanine complexes : preparation and investigation of properties |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
|
| |
Volume |
45 |
Issue |
32 |
Pages |
14815-14821 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Photoactive layers based on aryl- and aryloxy-substituted naphthalocyanines and conductive polymer poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) were prepared using the spin-coating technique and their conductivity was tested in dark and under illumination. For this purpose novel octa-2-naphthoxy-substituted naphthalocyanines were synthesized starting from 6,7-di(2-naphthoxy)naphthalene-2,3-dicarbonitrile. For those novel naphthalocyanine complexes, spectral and electrochemical data were measured and compared with corresponding ones for other aryl-substituted analogues. In comparison to the previously studied naphthalocyanines with alkyl- and phenyl- groups, the formal oxidation and reduction potentials were rather similar. All target complexes demonstrate intense near-infrared absorption at 760-790 nm, which is about 30 nm bathochromically shifted in thin films. The photo-resistive effect was found increasing from composites comprised of naphthoxy- to phenyl-substituted naphthalocyanines. This peculiarity was explained by using optical and atomic force microscopy in terms of different sizes of aggregates formed. The photo-response time for novel composited was approximately 3 s, which is about 20 times faster than measured previously for the films deposited via the drop-casting technique. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000680389800001 |
Publication Date |
2021-07-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
3.269 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.269 |
|
| |
Call Number |
UA @ admin @ c:irua:179884 |
Serial |
8379 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dubinina, T.V.; Moiseeva, E.O.; Astvatsaturov, D.A.; Borisova, N.E.; Tarakanov, P.A.; Trashin, S.A.; De Wael, K.; Tomilova, L.G. |
|
| |
Title |
Novel 2-naphthyl substituted zinc naphthalocyanine : synthesis, optical, electrochemical and spectroelectrochemical properties |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
|
| |
Volume |
44 |
Issue |
19 |
Pages |
7849-7857 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
New zinc naphthalocyanine with bulky 2-naphthyl groups was obtained. Aggregation drastically influences its optical and electrochemical behavior. Spectroelectrochemistry helps to establish the oxidation potential and reveals unusual color change. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000536157700023 |
Publication Date |
2020-04-22 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.3 |
Times cited |
1 |
Open Access |
|
|
| |
Notes |
; Synthesis, identification and optical studies of target compounds were supported by the Russian Science Foundation Grant No 19-73-00099. Electrochemical and spectroelectrochemical measurements were supported by ERA.Net RUS Plus Plasmon Electrolight and FWO funding (RFBR No 18-53-76006 ERA). Fluorescence studies were supported by the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grant MD-3847.2019.3). The NMR spectroscopic measurements were carried out in the Laboratory of Magnetic Tomography and Spectroscopy, Faculty of Fundamental Medicine of Moscow State University. ; |
Approved |
Most recent IF: 3.3; 2020 IF: 3.269 |
|
| |
Call Number |
UA @ admin @ c:irua:168952 |
Serial |
6570 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Daems, E.; Moro, G.; Berghmans, H.; Moretto, L.M.; Dewilde, S.; Angelini, A.; Sobott, F.; De Wael, K. |
|
| |
Title |
Native mass spectrometry for the design and selection of protein bioreceptors for perfluorinated compounds |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Analyst |
Abbreviated Journal |
Analyst |
|
| |
Volume |
146 |
Issue |
6 |
Pages |
2065-2073 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Biosensing platforms are answering the increasing demand for analytical tools for environmental monitoring of small molecules, such as per- and polyfluoroalkyl substances (PFAS). By transferring toxicological findings in bioreceptor design we can develop innovative pathways for biosensor design. Indeed, toxicological studies provide fundamental information about PFAS-biomolecule complexes that can help evaluate the applicability of the latter as bioreceptors. The toolbox of native mass spectrometry (MS) can support this evaluation, as shown by the two case studies reported in this work. The analysis of model proteins’ (i.e. albumin, haemoglobin, cytochrome c and neuroglobin) interactions with well-known PFAS, such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), demonstrated the potential of this native MS screening approach. In the first case study, untreated albumin and delipidated albumin were compared in the presence and absence of PFOA confirming that the delipidation step increases albumin affinity for PFOA without affecting protein stability. In the second case study, the applicability of our methodology to identify potential bioreceptors for PFOS/PFOA was extended to other proteins. Structurally related haemoglobin and neuroglobin revealed a 1 : 1 complex, whereas no binding was observed for cytochrome c. These studies have value as a proof-of-concept for a general application of native MS to identify bioreceptors for toxic compounds. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000631575100031 |
Publication Date |
2021-01-18 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2654; 1364-5528 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
3.885 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.885 |
|
| |
Call Number |
UA @ admin @ c:irua:177074 |
Serial |
8294 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Thiruvottriyur Shanmugam, S.; Trashin, S.; De Wael, K. |
|
| |
Title |
Gold-sputtered microelectrodes with built-in gold reference and counter electrodes for electrochemical DNA detection |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Analyst |
Abbreviated Journal |
Analyst |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Gold-sputtered microelectrodes with built-in gold reference and counter electrodes represent a promising platform for the development of disposable DNA sensors. Pretreating gold electrode surfaces and immobilization of DNA thereon is commonly employed in biosensing applications. However, with no scientific or practical guidelines to prepare a DNA sensor using these miniature gold-sputtered microelectrodes, cleaning and immobilization steps need to be systematically optimized and updated. In this work, we present efficient cleaning and modification of miniaturized gold-sputtered microelectrodes with thiolated DNA probes for DNA detection. Additional discussions on subtleties and nuances involved at each stage of pretreating and modifying gold-sputtered microelectrodes are included to present a robust, well-founded protocol. It was evident that the insights on cleaning polycrystalline gold disk electrodes with a benchmark electrode surface for DNA sensors, cannot be transferred to clean these miniature gold-sputtered microelectrodes. Therefore, a comparison between five different cleaning protocols was made to find the optimal one for gold-sputtered microelectrodes. Additionally, two principally different immobilization techniques for gold-sputtered microelectrode modification with thiolated ssDNA were compared i.e., immobilization through passive chemisorption and potential perturbation were compared in terms of thiol-specific attachment and thiol-unspecific adsorption through nitrogenous bases. The hybridization performance of these prepared electrodes was characterized by their sensitive complementary DNA capturing ability, detected by a standard alkaline phosphatase assay. Immobilization through passive chemisorption proved to be efficient in capturing the complementary target DNA with a detection limit of 0.14 nM and sensitivity of 9.38 A M−1 cm2. In general, this work presents a comprehensive understanding of cleaning, modification and performance of gold-sputtered microelectrodes with built-in gold reference and counter electrodes for both fundamental investigations and practical DNA sensing applications. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000592315100017 |
Publication Date |
2020-09-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2654 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.2 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 4.2; 2020 IF: 3.885 |
|
| |
Call Number |
UA @ admin @ c:irua:172447 |
Serial |
6527 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Jong, M.; Florea, A.; Daems, D.; Van Loon, J.; Samyn, N.; De Wael, K. |
|
| |
Title |
Electrochemical Analysis of Speedball-like Polydrug Samples |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Analyst |
Abbreviated Journal |
Analyst |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Product development |
|
| |
Abstract |
Increasing global production, trafficking and consumption of drugs of abuse cause an emerging threat to people’s health and safety. Electrochemical approaches have proven to be useful for on-site analysis of drugs of abuse. However, few attention has been focused on the analysis of polydrug samples, despite these samples causing severe health concerns, certainly when stimulants and depressants are combined, as is the case for Speedball, a mixture of cocaine and heroin. In this work, we provide solutions for the selective detection of cocaine (stimulant) in polydrug samples adulterated with heroin and codeine (depressants). The presence of either one of these compounds in cocaine street samples leads to an overlap with the cocaine signal in square-wave voltammetry measurements at unmodified carbon screen-printed electrodes, leading to inconclusive screening results in the field. The provided solutions to this problem consist of two parallel approaches: (i) cathodic pretreatment of the carbon screen-printed electrode surface prior to measurement in both alkaline and neutral conditions; (ii) electropolymerization of orthophenylenediamine on graphene modified carbon screen-printed electrodes prior to measurement in neutral conditions. Both strategies allow simultaneous detection of cocaine and heroin in speedball samples as well as simultaneous detection of cocaine and codeine. Implementing these strategies in portable devices holds great potential for significantly improved accuracy of on-site cocaine screening in polydrug samples. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000568961600011 |
Publication Date |
2020-07-28 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2654 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.2 |
Times cited |
|
Open Access |
|
|
| |
Notes |
This work was supported by IOF-SBO and IOF-POC from University of Antwerp, Antwerp, Belgium; and VLAIO IM [HBC.2019.2181], Brussels, Belgium. |
Approved |
Most recent IF: 4.2; 2020 IF: 3.885 |
|
| |
Call Number |
AXES @ axes @c:irua:170444 |
Serial |
6395 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Florea, A.; Cowen, T.; Piletsky, S.; De Wael, K. |
|
| |
Title |
Electrochemical analysis of cocaine in real samples based on electrodeposited biomimetic affinity ligands |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
The analyst |
Abbreviated Journal |
Analyst |
|
| |
Volume |
144 |
Issue |
15 |
Pages |
4639-4646 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
A selective electrochemical sensor for direct detection of cocaine was developed based on molecularly imprinted polymers electropolymerized onto graphene-modified electrodes. Palladium nanoparticles were integrated in the sensing layer for the benefit of enhancing the communication between imprinted sites and electrode and improving their homogenous distribution. The molecularly imprinted polymer was synthesized by cyclic voltammetry using p-aminobenzoic acid as high affinity monomer selected by computational modeling, and cocaine as template molecule. Experimental parameters related to the electrochemical deposition of palladium nanoparticles, pH, composition of electropolymerization mixture, extraction and rebinding condition were studied and optimized. Under optimized conditions the oxidation peak current varied linearly with cocaine concentration in the range of 100-500 µM, with a detection limit of 50 µM (RSD 0.71%, n=3). The molecularly imprinted sensor was able to detect cocaine in saliva and river water with good recoveries after sample pretreatment and was successfully applied for screening real street samples for cocaine. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000476812000021 |
Publication Date |
2019-06-10 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2654 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.885 |
Times cited |
3 |
Open Access |
|
|
| |
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. ; |
Approved |
Most recent IF: 3.885 |
|
| |
Call Number |
UA @ admin @ c:irua:160062 |
Serial |
5586 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kosov, A.D.; Dubrinina, T.V.; Borisova, N.E.; Ivanov, A.V.; Drozdov, K.A.; Trashin, S.A.; De Wael, K.; Kotova, M.S.; Tomilova, L.G. |
|
| |
Title |
Novel phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements : optimized synthetic protocols and physicochemical properties |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
New journal of chemistry |
Abbreviated Journal |
New J Chem |
|
| |
Volume |
43 |
Issue |
7 |
Pages |
3153-3161 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Novel synthetic protocols based on both template and multi-step methods were developed for phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements (Y, Eu, Gd, Dy, Er and Lu). p-Hydroquinone was employed as a reaction medium and as a reducing agent in the process of porphyrazine macrocycle formation. Both thermal and microwave irradiation techniques were successfully applied for activation of the template macrocyclization process. An alternative multi-step approach involving the initial stage of free-base ligand formation was realized for the lutetium compound. The target complexes were identified by high-resolution mass spectrometry, infrared spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Electrochemical behavior in solution and UV-vis absorbance in solutions and films were studied as well. Shifts in the position of the Q band and oxidationreduction potentials in comparison with corresponding phthalocyanine analogues were noticed. Using the IR absorption spectra recorded in the temperature range of 170300 K, the position of the Fermi level of −4.7 ± 0.1 eV and a characteristic energy diagram were obtained for the erbium complex. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000459944500035 |
Publication Date |
2019-01-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.269 |
Times cited |
1 |
Open Access |
|
|
| |
Notes |
; We are grateful for main financial support from the Russian Foundation for Basic Research (Grant No. 16-33-60005 and 18-33-00519). Investigation of optical properties was supported by the Russian Science Foundation (Grant 17-13-01197). Electrochemical investigations were supported by ERA.Net RUS Plus Plasmon Electrolight and FWO funding (RFBR No. 18-53-76006 ERA). We also thank the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grants MK-3115.2018.3) and partial support from the framework of the State Assignment of 2019 (Theme 45.5 Creation of compounds with given physicochemical properties). Investigation of electrophysical properties was supported by the RFBR (Grant 16-07-00961). K. A. Drozdov and M. S. Kotova thank Prof. L. I. Ryabova for productive discussion of the electrophysical data. ; |
Approved |
Most recent IF: 3.269 |
|
| |
Call Number |
UA @ admin @ c:irua:156555 |
Serial |
5750 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Tarakanov, P.A.; Tarakanova, E.N.; Dorovatovskii, P.V.; Zubavichus, Y.V.; Khrustalev, V.N.; Trashin, S.A.; De Wael, K.; Neganova, M.E.; Mischenko, D.V.; Sessler, J.L.; Stuzhin, P.A.; Pushkarev, V.E.; Tomilova, L.G. |
|
| |
Title |
Optical readout of controlled monomer-dimer self-assembly |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
|
|
| |
Volume |
47 |
Issue |
40 |
Pages |
14169-14173 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
5,7-Substituted 1,4-diazepinoporphyrazine magnesium(II) complexes were synthesized via Mg(II)-alkoxide templated macrocyclization. A single crystal growth synchrotron diffraction analysis permitted what is to our knowledge the first structural characterization of a 1,4-diazepinoporphyrazine. It exists as a dimer in the solid state. In silico calculations supported by solution phase spectral studies involving a series of representative derivatives, provided insights into the factors governing dimerization of 1,4-diazepinoporphyrazines. The present 1,4-diazepinoporphyrazines serve as useful probes for understanding the determinants that guide dimermonomer equilibria and the self-assembly of phthalocyanine derivatives. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000447708900005 |
Publication Date |
2018-04-10 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
4 |
Open Access |
|
|
| |
Notes |
; We thank Dr Alexander V. Chernyak for recording the NMR spectra. Synthetic and optical spectroscopic studies in this work were supported by the RSF (Grant 17-73-10413). NMR studies were supported by the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grant MD-2991.2017.3). SR-XRD studies were supported by the RUDN University Program “5-100”. We also acknowledge support of electrochemical, in vitro and in vivo studies by the State Assignment (Theme 45.5 Creation of compounds with given physicochemical properties) and the facilities provided by the Center of Collective Use of IPAC RAS (Chernogolovka, Russia). Single-crystal X-ray measurements have been performed at the unique scientific facility Kurchatov Synchrotron Radiation Source supported by the Ministry of Education and Science of the Russian Federation (project code RFMEFI61917X0007). ; |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:151294 |
Serial |
5755 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vermeulen, M.; Sanyova, J.; Janssens, K.; Nuyts, G.; De Meyer, S.; De Wael, K. |
|
| |
Title |
The darkening of copper- or lead-based pigments explained by a structural modification of natural orpiment : a spectroscopic and electrochemical study |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
|
| |
Volume |
32 |
Issue |
7 |
Pages |
1331-1341 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
A combined Raman and electrochemical study of natural orpiment (As2S3), an arsenic sulfide pigment, was used to assess the quick formation of oxidized species such as arsenic oxide (As2O3) upon exposing the pigment to 405 nm or 532 nm monochromatic light while simultaneously recording the Raman spectra of the exposed sample. During this process, a distortion of the main band at 355 cm−1, associated with the stretching of the AsS3/2 pyramids of natural orpiment, was observed as well as an increased intensity of the 359 cm−1 band, corresponding to covalent AsAs bonds in natural orpiment. The distortion was accompanied by an overall decrease of the global Raman signal for natural orpiment, which could be explained by a loss in the crystal structure. The same phenomena were recorded in reference natural orpiment model paint samples stored for a long time together with verdigris (Cu(OH)2·(CH3COO)2·5H2O) and minium (Pb3O4) paints, the latter two appearing darkened on their sides closest to the orpiment sample as well as in several historical samples containing natural orpiment mixed with various blue pigments. By SEM-EDX and XRPD analysis, respectively on loose material and cast thin-sections of model paint samples, the darkening was identified as dark sulfide species such as chalcocite (Cu2S) and galena (PbS), suggesting the release of volatile sulfide or related species by the natural orpiment paint. XANES analyses of paint samples presenting AsAs bond increase indicated the presence of sulfur species most likely identified as organosulfur compounds formed upon the AsAs bond formation and explained the darkening of the Cu- and Pb-based pigments. To the best of our knowledge, this article reports for the first time the light-induced formation of AsAs bonds in natural orpiment used as an artists' pigment and objectively demonstrates the incompatibility between orpiment and (arsenic) sulfide-sensitive pigments. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000404998500007 |
Publication Date |
2017-05-31 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.379 |
Times cited |
10 |
Open Access |
|
|
| |
Notes |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). We gratefully acknowledge Julie Arslanoglu (Conservation and Scientific Research Department at the Metropolitan Museum of Art, New York, USA) for providing us the orpiment, verdigris and minium mock-up samples. We gratefully acknowledge the Paul Scherrer Institut, Villigen, Switzerland and the German Electron Synchrotron (DESY) for provision of synchrotron radiation beamtimes at respectively beamlines of the SLS and Petra III. ; |
Approved |
Most recent IF: 3.379 |
|
| |
Call Number |
UA @ admin @ c:irua:144384 |
Serial |
5564 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hrdlickova Kuckova, S.; Hamidi-Asl, E.; Sofer, Z.; Marvan, P.; De Wael, K.; Sanyova, J.; Janssens, K. |
|
| |
Title |
A simplified protocol for usage of new immuno-SERS probes for detection of casein, collagens and ovalbumin in cross-sections of artworks |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Analytical methods |
Abbreviated Journal |
Anal Methods-Uk |
|
| |
Volume |
10 |
Issue |
9 |
Pages |
1054-1062 |
|
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Although it is now relatively straightforward to identify protein binders in works of art, their proper localization within the corresponding layer still represents a significant analytical challenge. Until now, the identification of proteins has mainly been performed by peptide mass fingerprinting using mass spectrometric methods and their localization in polished paint cross-sections have been realized by optical microscopy via the use of fluorescent stain Sypro Ruby (SR). In this work we propose a simplified protocol for immuno-surface enhanced Raman scattering (immuno-SERS) using gold nanoparticles attached to biphenyl-4,4-dithiol (BPDT) as the SERS-nanotag. These nanoparticles are easily obtainable in the lab and have been used to label multilayered mock up samples prepared as cross-sections to estimate the detection limits of the suggested method. The layers contain egg, casein, and different animal glues binders (prepared in various ratios with linseed oil or a carbohydrate component) mixed with the pigments azurite, vermilion and chalk. The sensitivity of staining agent SR is compared to that of the immuno-SERS protocol for the first time. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000426696100017 |
Publication Date |
2018-02-02 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1759-9660 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.9 |
Times cited |
3 |
Open Access |
|
|
| |
Notes |
; The authors wish to acknowledge the Fund for Scientific Research-Flanders (FWO-Vlaanderen) for the support to act as a Postdoctoral Fellow – Pegasus of the Research Foundation – Flanders, and the grant from Specific University research (MSMT No. 20/2017) from the Czech Republic. This work was supported by the project Advanced Functional Nanorobots (reg. No. CZ.02.1.01/0.0/0.0/15_003/ 0000444 financed by the EFRR). Zdenek Sofer and Petr Marvan were supported by specific university research (MSMT No. 20-SVV/2018). ; |
Approved |
Most recent IF: 1.9 |
|
| |
Call Number |
UA @ admin @ c:irua:148803 |
Serial |
5831 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Loreto, S.; Cuypers, B.; Brokken, J.; Van Doorslaer, S.; De Wael, K.; Meynen, V. |
|
| |
Title |
The effect of the buffer solution on the adsorption and stability of horse heart myoglobin on commercial mesoporous titanium dioxide : a matter of the right choice |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
| |
Volume |
19 |
Issue |
21 |
Pages |
13503-13514 |
|
| |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Despite the numerous studies on the adsorption of different proteins onto mesoporous titanium dioxide and indications on the important role of buffer solutions in bioactivity, a systematic study on the impact of the buffer on the protein incorporation into porous substrates is still lacking. We here studied the interaction between a commercial mesoporous TiO2 and three of the most used buffers for protein incorporation, i.e. HEPES, Tris and phosphate buffer. In addition, this paper analyzes the adsorption of horse heart myoglobin (hhMb) onto commercial mesoporous TiO2 as a model system to test the influence of buffers on the protein incorporation behavior in mesoporous TiO2. N2 sorption analysis, FT-IR and TGA/DTG measurements were used to evaluate the interaction between the buffers and the TiO2 surface, and the effect of such an interaction on hhMb adsorption. Cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) were used to detect changes in the microenvironment surrounding the heme. The three buffers show a completely different interaction with the TiO2 surface, which drastically affects the adsorption of myoglobin as well as its structure and electrochemical activity. Therefore, special attention is required while choosing the buffer medium to avoid misguided evaluation of protein adsorption on mesoporous TiO2. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000402488300013 |
Publication Date |
2017-04-27 |
|
| |
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 |
2 |
Open Access |
|
|
| |
Notes |
; We are grateful to Gert Nuyts for performing the XRF measurements, and Dr Stanislav Trashin for his assistance during the electrochemical experiments. This work is supported by the Research Foundation – Flanders (FWO) (grant G.0687.13) and the University of Antwerp (BOF project). ; |
Approved |
Most recent IF: 4.123 |
|
| |
Call Number |
UA @ admin @ c:irua:143514 |
Serial |
5582 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
De Jong, M.; Sleegers, N.; Kim, J.; Van Durme, F.; Samyn, N.; Wang, J.; De Wael, K. |
|
| |
Title |
Electrochemical fingerprint of street samples for fast on-site screening of cocaine in seized drug powders |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
|
| |
Volume |
|
Issue |
|
Pages |
1-7 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
We report on a wearable fingertip sensor for on-the-spot identification of cocaine and its cutting agents in street samples. Traditionally, on-site screening is performed by means of colour tests which are difficult to interpret and lack selectivity. By presenting the distinct voltammetric response of cocaine, cutting agents, binary mixtures of cocaine and street samples in solution and powder street samples, we were able to elucidate the electrochemical fingerprint of all these compounds. The new electrochemical concept holds considerable promise as an on-site screening method. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000371021900094 |
Publication Date |
2016-01-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2041-6520 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.668 |
Times cited |
37 |
Open Access |
|
|
| |
Notes |
; The authors acknowledge BELSPO for funding the APTADRU project (BR/314/PI/ APTADRU). ; |
Approved |
Most recent IF: 8.668 |
|
| |
Call Number |
UA @ admin @ c:irua:130404 |
Serial |
5591 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Slavkovic, S.; Shoara, A.A.; Churcher, Z.R.; Daems, E.; De Wael, K.; Sobott, F.; Johnson, P.E. |
|
| |
Title |
DNA binding by the antimalarial compound artemisinin |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Scientific reports |
Abbreviated Journal |
|
|
| |
Volume |
12 |
Issue |
1 |
Pages |
133 |
|
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
|
| |
Abstract |
Artemisinin (ART) is a vital medicinal compound that is used alone or as part of a combination therapy against malaria. ART is thought to function by attaching to heme covalently and alkylating a range of proteins. Using a combination of biophysical methods, we demonstrate that ART is bound by three-way junction and duplex containing DNA molecules. Binding of ART by DNA is first shown for the cocaine-binding DNA aptamer and extensively studied using this DNA molecule. Isothermal titration calorimetry methods show that the binding of ART is both entropically and enthalpically driven at physiological NaCl concentration. Native mass spectrometry methods confirm DNA binding and show that a non-covalent complex is formed. Nuclear magnetic resonance spectroscopy shows that ART binds at the three-way junction of the cocaine-binding aptamer, and that binding results in the folding of the structure-switching variant of this aptamer. This structure-switching ability was exploited using the photochrome aptamer switch assay to demonstrate that ART can be detected using this biosensing assay. This study is the first to demonstrate the DNA binding ability of ART and should lay the foundation for further work to study implications of DNA binding for the antimalarial activity of ART. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000740510500120 |
Publication Date |
2022-01-07 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:184507 |
Serial |
8851 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Meysman, F.J.R.; Cornelissen, R.; Trashin, S.; Bonne, R.; Hidalgo-Martinez, S.; van der Veen, J.; Blom, C.J.; Karman, C.; Hou, J.-L.; Eachambadi, R.T.; Geelhoed, J.S.; De Wael, K.; Beaumont, H.J.E.; Cleuren, B.; Valcke, R.; van der Zant, H.S.J.; Boschker, H.T.S.; Manca, J.V. |
|
| |
Title |
A highly conductive fibre network enables centimetre-scale electron transport in multicellular cable bacteria |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
| |
Volume |
10 |
Issue |
10 |
Pages |
4120 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Biological electron transport is classically thought to occur over nanometre distances, yet recent studies suggest that electrical currents can run along centimetre-long cable bacteria. The phenomenon remains elusive, however, as currents have not been directly measured, nor have the conductive structures been identified. Here we demonstrate that cable bacteria conduct electrons over centimetre distances via highly conductive fibres embedded in the cell envelope. Direct electrode measurements reveal nanoampere currents in intact filaments up to 10.1 mm long (>2000 adjacent cells). A network of parallel periplasmic fibres displays a high conductivity (up to 79 S cm(-1)), explaining currents measured through intact filaments. Conductance rapidly declines upon exposure to air, but remains stable under vacuum, demonstrating that charge transfer is electronic rather than ionic. Our finding of a biological structure that efficiently guides electrical currents over long distances greatly expands the paradigm of biological charge transport and could enable new bio-electronic applications. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000485216900006 |
Publication Date |
2019-09-11 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
12.124 |
Times cited |
10 |
Open Access |
|
|
| |
Notes |
; This research was financially supported by the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) through ERC Grant 306933 (F.J.R.M.), the Research Foundation Flanders (FWO project grant G031416N), and the Netherlands Organisation for Scientific Research (VICI grant 016.VICI.170.072 to F.J.R.M.). H.J.E.B., C.J.B. and H.S.J.Z. were supported by the Netherlands Organisation for Scientific Research (NWO/OCW), as part of the Frontiers of Nanoscience program. R.B. is supported by an 'aspirant' grant from Research Foundation Flanders (FWO). We thank Laurine Burdorf (UAntwerpen) for help with Thiothrix cultivation, Marlies Nijemeisland (Faculty of Aerospace, TU Delft) for assistance with Raman microscopy, and Jan D'Haen (UHasselt) and Renaat Dasseville (UGent) for help with EM imaging. ; |
Approved |
Most recent IF: 12.124 |
|
| |
Call Number |
UA @ admin @ c:irua:162795 |
Serial |
5451 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
De Henau, S.; Tilleman, L.; Vangheel, M.; Luyckx, E.; Trashin, S.; Pauwels, M.; Germani, F.; Vlaeminck, C.; Vanfleteren, J.R.; Bert, W.; Pesce, A.; Nardini, M.; Bolognesi, M.; De Wael, K.; Moens, L.; Dewilde, S.; Braeckman, B.P. |
|
| |
Title |
A redox signalling globin is essential for reproduction in Caenorhabditis elegans |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
| |
Volume |
6 |
Issue |
|
Pages |
8782 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Moderate levels of reactive oxygen species (ROS) are now recognized as redox signalling molecules. However, thus far, only mitochondria and NADPH oxidases have been identified as cellular sources of ROS in signalling. Here we identify a globin (GLB-12) that produces superoxide, a type of ROS, which serves as an essential signal for reproduction in C. elegans. We find that GLB-12 has an important role in the regulation of multiple aspects in germline development, including germ cell apoptosis. We further describe how GLB-12 displays specific molecular, biochemical and structural properties that allow this globin to act as a superoxide generator. In addition, both an intra- and extracellular superoxide dismutase act as key partners of GLB-12 to create a transmembrane redox signal. Our results show that a globin can function as a driving factor in redox signalling, and how this signal is regulated at the subcellular level by multiple control layers. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000367577100002 |
Publication Date |
2015-12-01 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
12.124 |
Times cited |
20 |
Open Access |
|
|
| |
Notes |
; We thank Dr K. Matsumoto and Dr T. Mizuno for kindly providing the mek-1(ks54) sek-1(km4) double mutant, the antibody anti-PMK-1 and technical advice on antibody use; Dr D. Kim for kindly providing the pDK177 RNAi strain; Dr M. Ubbink and Dr Q. Bashir for providing CCP; Dr K. Oegema and the OD lab for sharing technical expertise; M. Couvreur for assistance in generating transgenic lines; and Dr T. Dansen for the final support. Some strains were provided by the CGC, which is funded by the NIH Office of Research Infrastructure Programs (P40 OD010440). S.D.H. and F.G. are PhD fellows of the Fund for Scientific Research (FWO). Financial support to S.D. and L.M. was provided by the University of Antwerp (BOF UA TOP 2006), to K.D.W., S.D. and S.T. by the University of Antwerp (BOF-GOA) and to S.D., L.M., B.P.B., by FWO project G.0247.09. ; |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
|
| |
Call Number |
UA @ admin @ c:irua:129310 |
Serial |
5809 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Trashin, S.; Rahemi, V.; Ramji, K.; Neven, L.; Gorun, S.M.; De Wael, K. |
|
| |
Title |
Singlet oxygen-based electrosensing by molecular photosensitizers |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
| |
Volume |
8 |
Issue |
|
Pages |
16108 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Enzyme-based electrochemical biosensors are an inspiration for the development of (bio)analytical techniques. However, the instability and reproducibility of the reactivity of enzymes, combined with the need for chemical reagents for sensing remain challenges for the construction of useful devices. Here we present a sensing strategy inspired by the advantages of enzymes and photoelectrochemical sensing, namely the integration of aerobic photocatalysis and electrochemical analysis. The photosensitizer, a bioinspired perfluorinated Zn phthalocyanine, generates singlet-oxygen from air under visible light illumination and oxidizes analytes, yielding electrochemically-detectable products while resisting the oxidizing species it produces. Compared with enzymatic detection methods, the proposed strategy uses air instead of internally added reactive reagents, features intrinsic baseline correction via on/off light switching and shows C-F bonds-type enhanced stability. It also affords selectivity imparted by the catalytic process and nano-level detection, such as 20 nM amoxicillin in μl sample volumes. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000405466200002 |
Publication Date |
2017-07-14 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
12.124 |
Times cited |
26 |
Open Access |
|
|
| |
Notes |
; Evonik is thanked for providing samples of silicon and titanium oxides. Support from the National Science Foundation (SMG) for a portion of this work is gratefully acknowledged. FWO and UAntwerpen (BOF) are acknowledged for financial support. ; |
Approved |
Most recent IF: 12.124 |
|
| |
Call Number |
UA @ admin @ c:irua:144538 |
Serial |
5833 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Blidar, A.; Trashin, S.; Carrion, E.N.; Gorun, S.M.; Cristea, C.; De Wael, K. |
|
| |
Title |
Enhanced photoelectrochemical detection of an analyte triggered by its concentration by a singlet oxygen-generating fluoro photosensitizer |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Sensors |
Abbreviated Journal |
Acs Sensors |
|
| |
Volume |
5 |
Issue |
11 |
Pages |
3501-3509 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
The use of a photocatalyst (photosensitizer) which produces singlet oxygen instead of enzymes for oxidizing analytes creates opportunities for designing cost-efficient and sensitive photoelectrochemical sensors. We report that perfluoroisopropyl-substituted zinc phthalocyanine (F64PcZn) interacts specifically with a complex phenolic compound, the antibiotic rifampicin (RIF), but not with hydroquinone or another complex phenolic compound, the antibiotic doxycycline. The specificity is imparted by the selective preconcentration of RIF in the photocatalytic layer, as revealed by electrochemical and optical measurements, complemented by molecular modeling that confirms the important role of a hydrophobic cavity formed by the iso-perfluoropropyl groups of the photocatalyst. The preconcentration effect favorably enhances the RIF photoelectrochemical detection limit as well as sensitivity to nanomolar (ppb) concentrations, LOD = 7 nM (6 ppb) and 2.8 A.M-1.cm(-2), respectively. The selectivity to RIF, retained in the photosensitizer layer, is further enhanced by the selective removal of all unretained phenols via simple washing of the electrodes with pure buffer. The utility of the sensor for analyzing municipal wastewater was demonstrated. This first demonstration of enhanced selectivity and sensitivity due to intrinsic interactions of a molecular photocatalyst (photosensitizer) with an analyte, without use of a biorecognition element, may allow the design of related, robust, simple, and viable sensors. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000595550100021 |
Publication Date |
2020-10-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2379-3694 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.9 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 8.9; 2020 IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:176057 |
Serial |
7913 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ehirim, T.J.; Ozoemena, O.C.; Mwonga, P.V.; Haruna, A.B.; Mofokeng, T.P.; De Wael, K.; Ozoemena, K.I. |
|
| |
Title |
Onion-like carbons provide a favorable electrocatalytic platform for the sensitive detection of tramadol drug |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
ACS Omega |
Abbreviated Journal |
|
|
| |
Volume |
7 |
Issue |
51 |
Pages |
47892-47905 |
|
| |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
|
| |
Abstract |
This work reports the first study on the possible application of nanodiamond-derived onion-like carbons (OLCs), in comparison with conductive carbon black (CB), as an electrode platform for the electrocatalytic detection of tramadol (an important drug of abuse). The physicochemical properties of OLCs and CB were determined using X-ray diffraction (XRD), Raman, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and thermogravimetric analysis (TGA). The OLC exhibits, among others, higher surface area, more surface defects, and higher thermal stability than CB. From the electrochemical analysis (interrogated using cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy), it is shown that an OLC-modified glassy carbon electrode (GCE-OLC) allows faster electron transport and electrocatalysis toward tramadol compared to a GCE-CB. To establish the underlying science behind the high performance of the OLC, theoretical calculations (density functional theory (DFT) simulations) were conducted. DFT predicts that OLC allows for weaker surface binding of tramadol (Ead = -26.656 eV) and faster kinetic energy (K.E. = -155.815 Ha) than CB (Ead = -40.174 eV and -305.322 Ha). The GCE-OLC shows a linear calibration curve for tramadol over the range of similar to 55 to 392 mu M, with high sensitivity (0.0315 mu A/mu M) and low limit of detection (LoD) and quantification (LoQ) (3.8 and 12.7 mu M, respectively). The OLC-modified screen-printed electrode (SPE-OLC) was successfully applied for the sensitive detection of tramadol in real pharmaceutical formulations and human serum. The OLC-based electrochemical sensor promises to be useful for the sensitive and accurate detection of tramadol in clinics, quality control, and routine quantification of tramadol drugs in pharmaceutical formulations. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000903165200001 |
Publication Date |
2022-12-15 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2470-1343 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:193391 |
Serial |
8908 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K. |
|
| |
Title |
Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
|
| |
Volume |
32 |
Issue |
7 |
Pages |
2863-2873 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
Abstract |
The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000526394000016 |
Publication Date |
2020-04-14 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.6 |
Times cited |
8 |
Open Access |
OpenAccess |
|
| |
Notes |
Universiteit Antwerpen; Belgian Federal Science Policy Office; |
Approved |
Most recent IF: 8.6; 2020 IF: 9.466 |
|
| |
Call Number |
EMAT @ emat @c:irua:168819 |
Serial |
6363 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rahemi, V.; Trashin, S.; Hafideddine, Z.; Van Doorslaer, S.; Meynen, V.; Gorton, L.; De Wael, K. |
|
| |
Title |
Amperometric flow-injection analysis of phenols induced by reactive oxygen species generated under daylight irradiation of titania impregnated with horseradish peroxidase |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
92 |
Issue |
92 |
Pages |
3643-3649 |
|
| |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Titanium dioxide (TiO2) is a unique material for biosensing applications due to its capability of hosting enzymes. For the first time, we show that TiO2 can accumulate reactive oxygen species (ROS) under daylight irradiation and can support the catalytic cycle of horseradish peroxidase (HRP) without the need of H2O2 to be present in the solution. Phenolic compounds, such as hydroquinone (HQ) and 4-aminophenol (4-AP), were detected amperometrically in flow-injection analysis (FIA) mode via the use of an electrode modified with TiO2 impregnated with HRP. In contrast to the conventional detection scheme, no H2O2 was added to the analyte solution. Basically, the inherited ability of TiO2 to generate reactive oxygen species is used as a strategy to avoid adding H2O2 in the solution during the detection of phenolic compounds. Electron paramagnetic resonance (EPR) spectroscopy indicates the presence of ROS on titania which, in interaction with HRP, initiate the electrocatalysis toward phenolic compounds. The amperometric response to 4-AP was linear in the concentration range between 0.05 and 2 μM. The sensitivity was 0.51 A M–1 cm–2, and the limit of detection (LOD) 26 nM. The proposed sensor design opens new opportunities for the detection of phenolic traces by HRP-based electrochemical biosensors, yet in a more straightforward and sensitive way following green chemistry principles of avoiding the use of reactive and harmful chemical, such as H2O2. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000518234700023 |
Publication Date |
2020-01-27 |
|
| |
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 |
7.4 |
Times cited |
3 |
Open Access |
|
|
| |
Notes |
; The authors thank Scientific Reseatch-Flanders (F-WO) (grant 12T4219N) for funding. ; |
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:166241 |
Serial |
5463 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
De Jong, M.; Sleegers, N.; Florea, A.; Van Loon, J.; van Nuijs, A.L.N.; Samyn, N.; De Wael, K. |
|
| |
Title |
Unraveling the mechanisms behind the complete suppression of cocaine electrochemical signals by chlorpromazine, promethazine, procaine, and dextromethorphan |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
91 |
Issue |
24 |
Pages |
15453-15460 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre; Product development |
|
| |
Abstract |
The present work investigates the challenges accompanied by the electrochemical cocaine detection in physiological conditions (pH 7) in the presence of chlorpromazine, promethazine, procaine, and dextromethorphan, frequently used cutting agents in cocaine street samples. The problem translates into the absence of the cocaine oxidation signal (signal suppression) when in a mixture with one of these compounds, leading to false negative results. Although a solution to this problem was provided through earlier experiments of our group, the mechanisms behind the suppression are now fundamentally investigated via electrochemical and liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) strategies. The latter was used to confirm the passivation of the electrodes due to their interaction with promethazine and chlorpromazine. Electron transfer mechanisms were further identified via linear sweep voltammetry. Next, adsorption experiments were performed on the graphite screen printed electrodes both with and without potential assistance in order to confirm if the suppression of the cocaine signals is due to passivation induced by the cutting agents or their oxidized products. The proposed strategies allowed us to identify the mechanisms of cocaine suppression for each cutting agent mentioned. Suppression due to procaine and dextromethorphan is caused by fouling of the electrode surface by their oxidized forms, while for chlorpromazine and promethazine the suppression of the cocaine signal is related to the strong adsorption of these (nonoxidized) cutting agents onto the graphite electrode surface. These findings provide fundamental insights in possible suppression and other interfering mechanisms using electrochemistry in general not only in the drug detection sector. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000503910600018 |
Publication Date |
2019-11-14 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.32 |
Times cited |
|
Open Access |
|
|
| |
Notes |
; The authors acknowledge financial support from IOF-SBO/POC (UAntwerp) and the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:165727 |
Serial |
5887 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K. |
|
| |
Title |
Electrochemical strategies for adulterated heroin samples |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
91 |
Issue |
12 |
Pages |
7920-7928 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Electrochemical strategies to selectively detect heroin in street samples without the use of complicated electrode modifications were developed for the first time. For this purpose, heroin, mixing agents (adulterants, cutting agent, and impurities), and their binary mixtures were subjected to square wave voltammetry measurements at bare graphite electrodes at pH 7.0 and pH 12.0, in order to elucidate the unique electrochemical fingerprint of heroin and mixing agents as well as possible interferences or reciprocal influences. Adjusting the pH from pH 7.0 to pH 12.0 allowed a more accurate detection of heroin in the presence of most common mixing agents. Furthermore, the benefit of introducing a preconditioning step prior to running square wave voltammetry on the electrochemical fingerprint enrichment was explored. Mixtures of heroin with other drugs (cocaine, 3,4-methylenedioxymethamphetamine, and morphine) were also tested to explore the possibility of their discrimination and simultaneous detection. The feasibility of the proposed electrochemical strategies was tested on realistic heroin street samples from forensic cases, showing promising results for fast, on-site detection tools of drugs of abuse. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000472682000056 |
Publication Date |
2019-05-30 |
|
| |
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 |
2 |
Open Access |
|
|
| |
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge IOF (UAntwerp) and Belspo for financial support. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:160061 |
Serial |
5596 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K. |
|
| |
Title |
Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
91 |
Issue |
18 |
Pages |
11582-11588 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000487156900016 |
Publication Date |
2019-08-20 |
|
| |
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 |
2 |
Open Access |
|
|
| |
Notes |
; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:163784 |
Serial |
5621 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. |
|
| |
Title |
Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
91 |
Issue |
3 |
Pages |
2035-2041 |
|
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
|
| |
Abstract |
Electrochemistry and exploiting electrochemical fingerprints is a potent approach to address newly emerging surveillance needs, for instance for antibiotics. However, a comprehensive insight in the electrochemical oxidation behaviour and mechanism is re-quired for this sensing strategy. To address the lack in knowledge of the voltammetric behaviour of the cephalosporins antibiotics, a selection of cephalosporin antibiotics and two main intermediates were subjected to an electrochemical study of their redox behaviour by means of pulsed voltammetric techniques and small-scale electrolysis combined with HPLC-MS/MS analyses. Sur-prisingly, the detected oxidation products did not fit the earlier suggested oxidation of the sulfur group to the corresponding sul-foxide. The influence of different side chains, both at the three and the seven position of the β-lactam core structure on the elec-trochemical fingerprint were investigated. Additional oxidation signals at lower potentials were elucidated and linked to different side chains. These signals were further exploited to allow simultaneous detection of different cephalosporins in one voltammetric sweep. These fundamental insights can become the building blocks for an new on-site screening method. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000458220300055 |
Publication Date |
2019-01-03 |
|
| |
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 |
6 |
Open Access |
|
|
| |
Notes |
; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:156046 |
Serial |
5497 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
De Jong, M.; Florea, A.; Eliaerts, J.; Van Durme, F.; Samyn, N.; De Wael, K. |
|
| |
Title |
Tackling poor specificity of cocaine color tests by electrochemical strategies |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
90 |
Issue |
11 |
Pages |
6811-6819 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
This paper presents electrochemical strategies for the fast screening of cocaine and most common cutting agents found in seized drug samples. First, a study on the performance of Scott color tests on cocaine and a wide range of cutting agents is described. The cutting agents causing false positive or false negative results when in mixture with cocaine are identified. To overcome the lack of specificity of color tests, we further propose a fast screening strategy by means of square wave voltammetry on disposable graphite screen printed electrodes, which reveals the unique fingerprint of cocaine and cutting agents. By employing a forward and backward scan and by a dual pH strategy, we enrich the electrochemical fingerprint and enable the simultaneous detection of cocaine and cutting agents. The effectiveness of the developed strategies was tested for the detection of cocaine in seized cocaine samples and compared with the color tests. Moreover, we prove the usefulness of square wave voltammetry for predicting possible interfering agents in color tests, based on the reduction peak of cobalt thiocyanate. The developed electrochemical strategies allow for a quick screening of seized cocaine samples resulting in a selective identification of drugs and cutting agents. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000434893200066 |
Publication Date |
2018-05-09 |
|
| |
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 |
7 |
Open Access |
|
|
| |
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by Grants BR/314 /PI/APTADRU and IOF-SBO. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:151316 |
Serial |
5867 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K. |
|
| |
Title |
Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
90 |
Issue |
8 |
Pages |
5290-5297 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
|
| |
Abstract |
The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000430512200049 |
Publication Date |
2018-02-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.32 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:149528 |
Serial |
5693 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. |
|
| |
Title |
Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
89 |
Issue |
89 |
Pages |
3326-3334 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
| |
Language |
|
Wos |
000397478300015 |
Publication Date |
2017-02-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2700 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
OpenAccess |
|
| |
Notes |
; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ lucian @ c:irua:140886 |
Serial |
4451 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ayalew, E.; Janssens, K.; De Wael, K. |
|
| |
Title |
Unraveling the reactivity of minium towards bicarbonate and the role of lead oxides therein |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
88 |
Issue |
3 |
Pages |
1564-1569 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Understanding the reactivity of (semiconductor) pigments provides vital information on how to improve conservation strategies for works of art in order to avoid rapid degradation of the pigments. This study focuses on the photoactivity of minium (Pb3O4), a semiconductor pigment, that gives rise to strong discoloration phenomena upon exposure to various environmental conditions. To demonstrate its photoactivity, an electrochemical setup with minium-modified graphite electrode (C|Pb3O4) was used. It is confirmed that minium is a p-type semiconductor which is photoactive during illumination and becomes inactive in the dark. Raman measurements confirm the formation of the degradation products. The photoactivity of a semiconductor pigment is partly defined by the presence of lead oxide (PbO) impurities; these introduce new states in the original band gap. It will be experi-mentally evidenced that the presence of PbO particles in minium leads to an upward shift of the valence band that reduces the band gap. Thus, upon photoexcitation, the electron/hole separation is more easily initialized. The PbO/Pb3O4 composite electrodes demonstrate a higher reductive photocurrent compared to the photocurrent registered at pure PbO or Pb3O4 modified electrodes. Upon exposure to light with energy close to and above the band gap, electrons are excited from the valence band to the conduction band to initialize the reduction of Pb(IV) to Pb(II), resulting in the initial formation of PbO. However in the presence of bicarbonate ions, a significantly higher photoreduction current is recorded since the PbO reacts further to form hydrocerussite. Therefore the presence of bicarbonates in the environment stimulates the photodecomposition process of minium and plays an important role in the degradation process. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000369471100014 |
Publication Date |
2015-12-31 |
|
| |
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 |
9 |
Open Access |
|
|
| |
Notes |
; The authors acknowledge Sanne Aerts from the Laboratory of Adsorption and Catalysis (LADCA) of the University of Antwerp for her help with the UV-vis-DR. Financial support from the SOLARPAINT BOF-GOA project (University of Antwerp Research Council) is acknowledged. The authors are also indebted to F. Vanmeert for performing the XRD measurements. ; |
Approved |
Most recent IF: 6.32 |
|
| |
Call Number |
UA @ admin @ c:irua:129963 |
Serial |
5888 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ranjbari, E.; Hadjmohammadi, M.R.; Kiekens, F.; De Wael, K. |
|
| |
Title |
Mixed hemi/ad-micelle sodium dodecyl sulfate-coated magnetic iron oxide nanoparticles for the efficient removal and trace determination of rhodamine-B and rhodamine-6G |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
87 |
Issue |
15 |
Pages |
7894-7901 |
|
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g1, respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L1 of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL1. Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000359277900056 |
Publication Date |
2015-07-08 |
|
| |
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 |
36 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: 6.32; 2015 IF: 5.636 |
|
| |
Call Number |
UA @ admin @ c:irua:126583 |
Serial |
5730 |
|
| 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 |
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 |
