| People | Locations | Statistics |
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| Naji, M. |
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| Motta, Antonella |
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| Aletan, Dirar |
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| Mohamed, Tarek |
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| Ertürk, Emre |
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| Taccardi, Nicola |
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| Kononenko, Denys |
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| Petrov, R. H. | Madrid |
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| Alshaaer, Mazen | Brussels |
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| Bih, L. |
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| Casati, R. |
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| Muller, Hermance |
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| Kočí, Jan | Prague |
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| Šuljagić, Marija |
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| Kalteremidou, Kalliopi-Artemi | Brussels |
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| Azam, Siraj |
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| Ospanova, Alyiya |
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| Blanpain, Bart |
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| Ali, M. A. |
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| Popa, V. |
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| Rančić, M. |
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| Ollier, Nadège |
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| Azevedo, Nuno Monteiro |
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| Landes, Michael |
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| Rignanese, Gian-Marco |
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Weidner, Tobias
Aarhus University
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (29/29 displayed)
- 2022Peptide Orientation at Emulsion Nanointerfaces Dramatically Different from Flat Surfacescitations
- 2021Windowless detection geometry for sum frequency scattering spectroscopy in the C-D and amide i regionscitations
- 2021Insects use lubricants to minimize friction and wear in leg jointscitations
- 2020Role of Surface Chemistry in the Superhydrophobicity of the Springtail Orchesella cincta (Insecta:Collembola)citations
- 2020Lasalocid Acid Antibiotic at a Membrane Surface Probed by Sum Frequency Generation Spectroscopycitations
- 2018Structure of von Willebrand factor A1 on polystyrene determined from experimental and calculated sum frequency generation spectracitations
- 2018The surface chemistry of iron oxide nanocrystalscitations
- 2018Effect of Internal Heteroatoms on Level Alignment at Metal/Molecular Monolayer/Si Interfacescitations
- 2016Kinetically Controlled Sequential Growth of Surface-Grafted Chiral Supramolecular Copolymerscitations
- 2016Differential surface activation of the A1 domain of von Willebrand factorcitations
- 2016Functionalization of nanocrystalline diamond films with phthalocyaninescitations
- 2015Multiscale Effects of Interfacial Polymer Confinement in Silica Nanocompositescitations
- 2013Effects of self-assembled monolayer structural order, surface homogeneity and surface energy on pentacene morphology and thin film transistor device performancecitations
- 2013SFG analysis of surface bound proteinscitations
- 2013Covalently attached organic monolayers onto silicon carbide from 1-alkynescitations
- 2013Molecular suction padscitations
- 2012Probing the orientation of electrostatically immobilized protein G B1 by time-of-flight secondary ion spectrometry, sum frequency generation, and near-edge X-ray adsorption fine structure spectroscopycitations
- 2012Zwitterionic dithiocarboxylates derived from N-heterocyclic carbenescitations
- 2012Bottom-contact small-molecule n-type organic field effect transistors achieved via simultaneous modification of electrode and dielectric surfacescitations
- 2012Solid-state densification of spun-cast self-assembled monolayers for use in ultra-thin hybrid dielectricscitations
- 2011Simultaneous modification of bottom-contact electrode and dielectric surfaces for organic thin-film transistors through single-component spin-cast monolayerscitations
- 2011Probing albumin adsorption onto calcium phosphates by x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometrycitations
- 2011Characterization of poly(sodium styrene sulfonate) thin films grafted from functionalized titanium surfacescitations
- 2010Probing the orientation of surface-immobilized protein G B1 using ToF-SIMS, sum frequency generation, and NEXAFS spectroscopycitations
- 2010Multi-technique Characterization of Adsorbed Peptide and Protein Orientationcitations
- 2010Structure and Order of Phosphonic Acid-Based Self-Assembled Monolayers on Si(100)citations
- 2010Effect of the phenyl ring orientation in the polystyrene buffer layer on the performance of pentacene thin-film transistorscitations
- 2009Self-Assembly of a Pyridine-Terminated Thiol Monolayer on Au(111)citations
- 2009Amide or Aminecitations
Places of action
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article
Probing the orientation of electrostatically immobilized protein G B1 by time-of-flight secondary ion spectrometry, sum frequency generation, and near-edge X-ray adsorption fine structure spectroscopy
Abstract
<p>To fully develop techniques that provide an accurate description of protein structure at a surface, we must start with a relatively simple model system before moving to increasingly complex systems. In this study, X-ray photoelectron spectroscopy (XPS), sum frequency generation spectroscopy (SFG), near-edge X-ray adsorption fine structure (NEXAFS) spectroscopy, and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to probe the orientation of Protein G B1 (6 kDa) immobilized onto both amine (NH <sub>3</sub> <sup>+</sup>) and carboxyl (COO <sup>-</sup>) functionalized gold. Previously, we have shown that we could successfully control orientation of a similar Protein G fragment via a cysteine-maleimide bond. In this investigation, to induce opposite end-on orientations, a charge distribution was created within the Protein G B1 fragment by first substituting specific negatively charged amino acids with neutral amino acids and then immobilizing the protein onto two oppositely charged self-assembled monolayer (SAM) surfaces (NH <sub>3</sub> <sup>+</sup> and COO <sup>-</sup>). Protein coverage, on both surfaces, was monitored by the change in the atomic % N, as determined by XPS. Spectral features within the SFG spectra, acquired for the protein adsorbed onto a NH <sub>3</sub> <sup>+</sup>-SAM surface, indicates that this electrostatic interaction does induce the protein to form an oriented monolayer on the SAM substrate. This corresponded to the polarization dependence of the spectral feature related to the NEXAFS N <sub>1s</sub>-to-π* transition of the β-sheet peptide bonds within the protein layer. ToF-SIMS data demonstrated a clear separation between the two samples based on the intensity differences of secondary ions stemming from amino acids located asymmetrically within Protein G B1 (methionine: 62 and 105 m/z; tyrosine: 107 and 137 m/z; leucine: 86 m/z). For a more quantitative examination of orientation, we developed a ratio comparing the sum of the intensities of secondary-ions stemming from the amino acid residues at either end of the protein. The 2-fold increase in this ratio, observed between the protein covered NH <sub>3</sub> <sup>+</sup> and COO <sup>-</sup> SAMs, indicates opposite orientations of the Protein G B1 fragment on the two different surfaces.</p>