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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. pdf  url
doi  openurl
  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 (up) 40 Pages 13606-13614  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  Abstract Detection of antigenic biomarkers present in trace amounts is of crucial importance for medical diagnosis. A parasitic disease, human toxocariasis, lacks an adequate diagnostic method despite its worldwide occurrence. The currently used serology tests may stay positive even years after a possibly unnoticed infection, whereas the direct detection of a re-infection or a still active infection remains a diagnostic challenge due to the low concentration of circulating parasitic antigens. We report a time-efficient sandwich immunosensor using small recombinant single-domain antibodies (nanobodies) derived from camelid heavy-chain antibodies specific to Toxocara canis antigens. An enhanced sensitivity to pg/mL levels is achieved by using a redox cycle consisting of a photocatalytic oxidation and electrochemical reduction steps. The photocatalytic oxidation is achieved by a photosensitizer generating singlet oxygen (1O2) that, in turn, readily reacts with p-nitrophenol enzymatically produced under alkaline conditions. The photooxidation produces benzoquinone that is electrochemically reduced to hydroquinone, generating an amperometric response. The light-driven process could be easily separated from the background, thus making amperometric detection more reliable. The proposed method for detection of the toxocariasis antigen marker shows superior performances compared to other detection schemes with the same nanobodies and outperforms by at least two orders of magnitude the assays based on regular antibodies, thus suggesting new opportunities for electrochemical immunoassays of challenging low levels of antigens.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000708550500025 Publication Date 2021-09-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 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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Author Bottari, F.; Daems, E.; de Vries, A.-M.; Van Wielendaele, P.; Trashin, S.; Blust, R.; Sobott, F.; Madder, A.; Martins, J.C.; De Wael, K. pdf  doi
openurl 
  Title Do aptamers always bind? The need for a multifaceted analytical approach when demonstrating binding affinity between aptamer and low molecular weight compounds Type A1 Journal article
  Year 2020 Publication Journal Of The American Chemical Society Abbreviated Journal J Am Chem Soc  
  Volume 142 Issue (up) 46 Pages jacs.0c08691-19630  
  Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Medical Biochemistry  
  Abstract In this manuscript, we compare different analytical methodologies to validate or disprove the binding capabilities of aptamer sequences. This was prompted by the lack of a universally accepted and robust quality control protocol for the characterization of aptamer performances coupled with the observation of independent yet inconsistent data sets in the literature. As an example, we chose three aptamers with a reported affinity in the nanomolar range for ampicillin, a β-lactam antibiotic, used as biorecognition elements in several detection strategies described in the literature. Application of a well-known colorimetric assay based on aggregation of gold nanoparticles (AuNPs) yielded conflicting results with respect to the original report. Therefore, ampicillin binding was evaluated in solution using isothermal titration calorimetry (ITC), native nano-electrospray ionization mass spectrometry (native nESI-MS), and 1H-nuclear magnetic resonance spectroscopy (1H NMR). By coupling the thermodynamic data obtained with ITC with the structural information on the binding event given by native nESI-MS and 1H NMR we could verify that none of the ampicillin aptamers show any specific binding with their intended target. The effect of AuNPs on the binding event was studied by both ITC and 1H NMR, again without providing positive evidence of ampicillin binding. To validate the performance of our analytical approach, we investigated two well-characterized aptamers for cocaine/quinine (MN4), chosen for its nanomolar range affinity, and l-argininamide (1OLD) to show the versatility of our approach. The results clearly indicate the need for a multifaceted analytical approach, to unequivocally establish the actual detection potential and performance of aptamers aimed at small organic molecules.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000592911000024 Publication Date 2020-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 15 Times cited Open Access  
  Notes Approved Most recent IF: 15; 2020 IF: 13.858  
  Call Number UA @ admin @ c:irua:173136 Serial 6488  
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Author Lybaert, J.; Trashin, S.; Maes, B.U.W.; De Wael, K.; Abbaspour Tehrani, K. pdf  url
doi  openurl
  Title Cooperative electrocatalytic and chemoselective alcohol oxidation by Shvo's catalyst Type A1 Journal article
  Year 2017 Publication Advanced synthesis and catalysis Abbreviated Journal Adv Synth Catal  
  Volume 359 Issue (up) 6 Pages 919-925  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)  
  Abstract A new electrocatalytic conversion of alcohols to ketones and aldehydes was developed based on an electrochemical study of Shvos complex. The oxidation of secondary alcohols was efficiently performed under mild conditions using a catalytic amount of Shvos catalyst, in combination with a sub-stoichiometric amount of 2,6-dimethoxy-1,4- benzoquinone in N,N-dimethylformamide at 80 8C. The hydroquinone thus formed is continuously reoxidized with the aid of an electrochemical device. Excellent yields for different ketones, aromatic as well as aliphatic and a,b-unsaturated ketones, are obtained. In addition, chemoselectivity towards oxidation of the secondary alcohol is achieved when converting vicinal diols such as 1,2-octanediol and 1,2-decanediol.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397584000003 Publication Date 2017-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1615-4150; 1615-4169 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.646 Times cited 4 Open Access  
  Notes ; This work was financially supported by the University of Antwerp (BOF), the Research Foundation – Flanders (FWO) and the Hercules Foundation. ; Approved Most recent IF: 5.646  
  Call Number UA @ admin @ c:irua:139795 Serial 5559  
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Author Trashin, S.; De Jong, M.; Meynen, V.; Dewilde, S.; De Wael, K. url  doi
openurl 
  Title Attaching redox proteins onto electrode surfaces by bis-silane Type A1 Journal article
  Year 2016 Publication ChemElectroChem Abbreviated Journal Chemelectrochem  
  Volume 3 Issue (up) 7 Pages 1035-1038  
  Keywords A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Immobilization of redox proteins on electrode surfaces is of special interest for mechanistic studies and applications because of a well-controlled redox state of protein molecules by a polarized electrode and fast electron transfer kinetics, free from diffusion limitation. Here, bis-organosilane (1,2-bis(trimethoxysilyl)ethane) was applied as a fresh solution in a pH 7 phosphate buffer without use of any organic solvent, sol-gel or mesoporous bulk matrix. A short aging period of 30 minutes before deposition on the electrodes was optimal for the immobilization of proteins. Three redox proteins (cytochrome c, neuroglobin and GLB-12) were confined to the gold surface of electrodes with high coverages and stability, indicating that the suggested technique is simple, efficient and generic in nature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000380043500001 Publication Date 2016-03-09  
  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 4 Open Access  
  Notes ; The authors thank the Fund for Scientific Research-Flanders (FWO) (Grant G.0687.13) and the GOA-BOF UA 2013-2016 (project ID 28312) for funding. ; Approved Most recent IF: 4.136  
  Call Number UA @ admin @ c:irua:132628 Serial 5485  
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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. pdf  url
doi  openurl
  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 (up) 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  
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Author Rahemi, V.; Trashin, S.; Hafideddine, Z.; Van Doorslaer, S.; Meynen, V.; Gorton, L.; De Wael, K. url  doi
openurl 
  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 (up) 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  
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