TY - JOUR A1 - Johansson, Fredrik O. L. A1 - Leitner, Torsten A1 - Bidermane, Ieva A1 - Born, Artur A1 - Föhlisch, Alexander A1 - Svensson, Svante A1 - Mårtensson, Nils A1 - Lindblad, Andreas T1 - Auger- and photoelectron coincidences of molecular O2 adsorbed on Ag(111) JF - Journal of electron spectroscopy and related phenomena : the international journal on theoretical and experimental aspects of electron spectroscopy N2 - The oxygen on Ag(111) system has been investigated with Auger electron-photoelectron coincidence spectroscopy (APECS). The coincidence spectra between O 1s core level photoelectrons and O KLL Auger electrons have been studied together with Ag(3)d/AgM4,5NN coincidences. We also describe the electron-electron coincidence spectrometer setup, CoESCA, consisting of two angle resolved time-of-flight spectrometers at a synchrotron light source. Contributions from molecular oxygen and chemisorbed oxygen are assigned using the coincidence data, conclusions are drawn primarily from the O 1s/O KLL data. The data acquisition and treatment procedure are also outlined. The chemisorbed oxygen species observed are relevant for the catalytic ethylene oxidation. KW - oxygen/Ag(111) KW - Auger electron KW - photoelectron KW - coincidence KW - APECS KW - spectroscopy Y1 - 2022 U6 - https://doi.org/10.1016/j.elspec.2022.147174 SN - 0368-2048 SN - 1873-2526 VL - 256 PB - Elsevier CY - New York, NY [u.a.] ER - TY - JOUR A1 - Laun, Konstantin A1 - Duffus, Benjamin R. A1 - Wahlefeld, Stefan A1 - Katz, Sagie A1 - Belger, Dennis Heinz A1 - Hildebrandt, Peter A1 - Mroginski, Maria Andrea A1 - Leimkühler, Silke A1 - Zebger, Ingo T1 - Infrared spectroscopy flucidates the inhibitor binding sites in a metal-dependent formate dehydrogenase JF - Chemistry - a European journal N2 - Biological carbon dioxide (CO2) reduction is an important step by which organisms form valuable energy-richer molecules required for further metabolic processes. The Mo-dependent formate dehydrogenase (FDH) from Rhodobacter capsulatus catalyzes reversible formate oxidation to CO2 at a bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor. To elucidate potential substrate binding sites relevant for the mechanism, we studied herein the interaction with the inhibitory molecules azide and cyanate, which are isoelectronic to CO2 and charged as formate. We employed infrared (IR) spectroscopy in combination with density functional theory (DFT) and inhibition kinetics. One distinct inhibitory molecule was found to bind to either a non-competitive or a competitive binding site in the secondary coordination sphere of the active site. Site-directed mutagenesis of key amino acid residues in the vicinity of the bis-MGD cofactor revealed changes in both non-competitive and competitive binding, whereby the inhibitor is in case of the latter interaction presumably bound between the cofactor and the adjacent Arg587. KW - CO2 reduction KW - DFT KW - formate oxidation KW - inhibition kinetics KW - IR KW - spectroscopy KW - molybdoenzyme Y1 - 2022 U6 - https://doi.org/10.1002/chem.202201091 SN - 0947-6539 SN - 1521-3765 PB - Wiley-VCH CY - Weinheim ER - TY - THES A1 - Sharma, Anjali T1 - Optical manipulation of multi-responsive microgels N2 - This dissertation focuses on the understanding of the optical manipulation of microgels dispersed in aqueous solution of azobenzene containing surfactant. The work consists of three parts where each part is a systematic investigation of the (1) photo-isomerization kinetics of the surfactant in complex with the microgel polymer matrix, (2) light driven diffusiosmosis (LDDO) in microgels and (3) photo-responsivity of microgel on complexation with spiropyran. The first part comprises three publications where the first one [P1] investigates the photo-isomerization kinetics and corresponding isomer composition at a photo-stationary state of the photo-sensitive surfactant conjugated with charged polymers or micro sized polymer networks to understand the structural response of such photo-sensitive complexes. We report that the photo-isomerization of the azobenzene-containing cationic surfactant is slower in a polymer complex compared to being purely dissolved in an aqueous solution. The surfactant aggregates near the polyelectrolyte chains at concentrations much lower than the bulk critical micelle concentration. This, along with the inhibition of the photo-isomerization kinetics due to steric hindrance within the densely packed aggregates, pushes the isomer-ratio to a higher trans-isomer concentration for all irradiation wavelengths. The second publication [P2] combines experimental results and non-adiabatic dynamic simulations for the same surfactant molecules embedded in the micelles with absorption spectroscopy measurements of micellar solutions to uncover the reasons responsible for the slowdown in photo induced trans → cis azobenzene isomerization at concentrations higher than the critical micelle concentration (CMC). The simulations reveal a decrease of isomerization quantum yields for molecules inside the micelles and observes a reduction of extinction coefficients upon micellization. These findings explain the deceleration of the trans → cis switching in micelles of the azobenzene-containing surfactants. Finally, the third publication [P3] focusses on the kinetics of adsorption and desorption of the same surfactant within anionic microgels in the dark and under continuous irradiation. Experimental data demonstrate, that microgels can serve as a selective absorber of the trans isomers. The interaction of the isomers with the gel matrix induces a remotely controllable collapse or swelling on appropriate irradiation wavelengths. Measuring the kinetics of the microgel size response and knowing the exact isomer composition under light exposure, we calculate the adsorption rate of the trans-isomers. The second part comprises two publications. The first publication [P4] reports on the phenomenon of light-driven diffusioosmotic (DO) long-range attractive and repulsive interactions between micro-sized objects, whose range extends several times the size of microparticles and can be adjusted to point towards or away from the particle by varying irradiation parameters such as intensity or wavelength of light. The phenomenon is fueled by the aforementioned photosensitive surfactant. The complex interaction of dynamic exchange of isomers and photo-isomerization rate yields to relative concentrations gradients of the isomers in the vicinity of micro-sized object inducing a local diffusioosmotic (DO) flow thereby making a surface act as a micropump. The second publication [P5] exclusively aims the visualization and investigation of the DO flows generated from microgels by using small tracer particles. Similar to micro sized objects, the flow is able to push adjacent tracers over distances several times larger than microgel size. Here we report that the direction and the strength of the l-LDDO depends on the intensity, irradiation wavelength and the amount of surfactant adsorbed by the microgel. For example, the flow pattern around a microgel is directed radially outward and can be maintained quasi-indefinitely under exposure at 455 nm when the trans:cis ratio is 2:1, whereas irradiation at 365 nm, generates a radially transient flow pattern, which inverts at lower intensities. Lastly, the third part consists of one publication [P6] which, unlike the previous works, reports on the study of the kinetics of photo- and thermo-switching of a new surfactant namely, spiropyran, upon exposure with light of different wavelengths and its interaction with p(NIPAM-AA) microgels. The surfactant being an amphiphile, switches between its ring closed spiropyran (SP) form and ring open merocyanine (MC) form which results in a change in the hydrophilic–hydrophobic balance of the surfactant as MC being a zwitterionic form along with the charged head group, generates three charges on the molecule. Therefore, the MC form of the surfactant is more hydrophilic than in the case of the neutral SP state. Here, we investigate the initial shrinkage of the gel particles via charge compensation on first exposure to SP molecules which results from the complex formation of the molecules with the gel matrix, triggering them to become photo responsive. The size and VPTT of the microgels during irradiation is shown to be a combination of heating up of the solution during light absorption by the surfactant (more pronounced in the case of UV irradiation) and the change in the hydrophobicity of the surfactant. N2 - Diese Dissertation befasst sich mit dem Verständnis der optischen Manipulation von Mikrogelen, die in einer wässrigen Lösung eines azobenzol-haltigen Tensides mit einer kationischen Kopfgruppe, welches licht-sensitiv ist, dispergiert sind. Die Arbeit besteht aus drei Teilen, wobei jeder Teil eine systematische Untersuchung der (1) Photoisomerisierungskinetik des Tensids im Komplex mit der Mikrogel-Polymermatrix, (2) einer daraus induzierten lokalen lichtinduzierten Diffusiosmose (eng. local light driven diffusio osmosis, l-LDDO) in der Nähe von Mikrogelen und (3) der photo-responsivität von Mikrogelen bei Komplexierung mit Spiropyran darstellt. Der erste Teil umfasst drei Veröffentlichungen, von denen die erste [P1] die Photoisomerisierungskinetik und die entsprechende Isomerenzusammensetzung im photostationären Zustand dieses Tensids in Komplex mit Polyelektrolyten oder mikroskopisch kleinen Polymernetzwerken untersucht. Dabei verläuft die trans-cis-Kinetik in einem Polymerkomplex langsamer als in reinen wässrigen Lösungen, da innerhalb der Polyelektrolytnetzwerken eine erhöhte Mizellisierungstendez des licht-schaltbare Tensides vorliegt. In einer Mizelle ist die geometrische Molekülstrukturänderung vom trans- zum cis-Isomer kinetisch durch sterische Hindernisse von dicht gepackten benachbarten Tensiden gehemmt und führt dazu, dass das Isomerverhältnis bei allen Bestrahlungswellenlängen zu höheren trans-Isomerkonzentration im photostationären Zustand verschoben sind. Diese experimentellen Ergebnisse werden in der zweiten Veröffentlichung [P2] mittels nicht-adiabatische dynamische Simulationen unterstützt, wobei die Ergebnisse zeigen, dass Moleküle, welche einer Mizelle aggregiert sind, eine Abnahme der Isomerisierungsquantenausbeute mit einer gleichzeitigen Verringerung der Extinktionskoeffizienten die Verlangsamung der Kinetik bestätigen. Die dritte Veröffentlichung [P3] befasst sich mit der Kinetik des dynamischen Austauschverhalten desselben Tensids in anionischen Mikrogelen im Dunkeln aber auch unter kontinuierlicher Beleuchtung. Dabei kann die Größe des Mikrogeles bei geeigneten Beleuchtungswellenlängen zu einem lichtgesteuerten Kollaps oder Schwellen des Mikrogeles vollständig reversible induziert werden. Möglich ist dies, weil die Mikrogele als selektiver Absorber für die trans-Isomere dienen. Durch die Messung der Kinetik der Größenänderung des Mikrogels und die Kenntnis der kinetischen Daten aus den vorigen Publikationen wurde die Adsorptionsrate des trans-Isomere zum Mikrogel berechnet. Der zweite Teil umfasst zwei Veröffentlichungen. Der erste [P4] berichtet über das tiefere Verständnis der lokalen lichtinduzierten Diffusioosmose (l-LDDO) an verschiedenen Mikroobjekten, die abstoßende oder anziehende Ströme induzieren. Triebkraft dieses Mechanismus ist eine Verschiebung des cis-Isomerengleichgewichtes bei Beleuchtung und dessen resultierenden Konzentrationsgradienten der Isomere in der Nähe dieser Objekte, welche durch eine komplexe Wechselwirkung zwischen dem dynamischen Austausch von beiden Isomeren und einer unterschiedlichen Photo-Isomerisierungsrate an der Grenzfläche im Vergleich zum Kontinuum vorliegen. Stärke des l-LDDO hängt von typischen Lichtparameter (Intensität und Wellenlänge) und der Größe und Oberfläche der Mikropartikels ab. Unter geeigneten Bedingungen (hohe Lichtintensität) kann fast jede Oberfläche als Mikropumpe wirken. Die zweite Publikation [P5] befasst sich mit der Visualisierung und Untersuchung des l-LDDO von Mikrogelen unter Verwendung von kleinen Tracerpartikel. Ähnlich wie bei mikroskopisch kleinen Objekten können auch hier benachbarte Tracer über Entfernungen um ein Vielfaches größer als die Größe des Mikrogels bewegt werden. Die Richtung und die Stärke des l-LDDO hängt von der Intensität, der Wellenlänge der Bestrahlung und der Menge des vom Mikrogel adsorbierten Tensids ab. So ist beispielsweise das Strömungsmuster um ein Mikrogel radial nach außen gerichtet und kann bei einer Bestrahlung mit blauem Licht (455 nm) quasi unbegrenzt aufrechterhalten werden, während eine Bestrahlung mit UV-Licht (365 nm) mit niedrigen Intensitäten ein temporäres radial verlaufendes Strömungsmuster zum Mikrogel erzeugt. Schließlich besteht der dritte und letzte Teil dieser Dissertation aus einer Veröffentlichung [P6], die im Gegensatz zu den vorangegangenen Arbeiten über die Untersuchung der Kinetik des Photo- und Thermoschaltens eines Spiropyran basierten Tensides mit einer kationischen Kopfgruppe bei der Bestrahlung mit Licht verschiedener Wellenlängen und seiner Wechselwirkung mit Mikrogelen berichtet. Das Tensid wechselt zwischen seiner ringgeschlossenen Spiropyranform (SP) und seiner ringoffenen Merocyaninform (MC), was zu einer Änderung des hydrophilen/hydrophoben Gleichgewichts des Tensids führt. Die anfängliche Schrumpfung der Mikrogele bei der ersten Exposition gegenüber SP-Molekülen wurde untersucht, die auf einen Ladungsausgleich durch die Komplexierung der Moleküle mit der Gelmatrix zurückzuführen ist, wodurch das Mikrogel lichtempfindlich wird. Darüber hinaus wird gezeigt, dass die Temperatur des Größen- und Volumenphasenübergangs der Mikrogele unter Beleuchtung eine Kombination aus dem lichtinduzierten Austauschverhalten und der Erwärmung der Lösung durch die Lichtabsorption des Tensids ist, die unter UV-Bestrahlung besonders ausgeprägt ist. KW - optical manipulation KW - microgel KW - kinetics KW - surfactant KW - photo-isomerization KW - polymer KW - azobenzene KW - spectroscopy KW - microscopy Y1 - 2023 ER - TY - JOUR A1 - Ehlert, Christopher A1 - Klamroth, Tillmann T1 - PSIXAS: A Psi4 plugin for efficient simulations of X-ray absorption spectra based on the transition-potential and Delta-Kohn-Sham method JF - Journal of computational chemistry : organic, inorganic, physical, biological N2 - Near edge X-ray absorption fine structure (NEXAFS) spectra and their pump-probe extension (PP-NEXAFS) offer insights into valence- and core-excited states. We present PSIXAS, a recent implementation for simulating NEXAFS and PP-NEXAFS spectra by means of the transition-potential and the Delta-Kohn-Sham method. The approach is implemented in form of a software plugin for the Psi4 code, which provides access to a wide selection of basis sets as well as density functionals. We briefly outline the theoretical foundation and the key aspects of the plugin. Then, we use the plugin to simulate PP-NEXAFS spectra of thymine, a system already investigated by others and us. It is found that larger, extended basis sets are needed to obtain more accurate absolute resonance positions. We further demonstrate that, in contrast to ordinary NEXAFS simulations, where the choice of the density functional plays a minor role for the shape of the spectrum, for PP-NEXAFS simulations the choice of the density functional is important. Especially hybrid functionals (which could not be used straightforwardly before to simulate PP-NEXAFS spectra) and their amount of "Hartree-Fock like" exact exchange affects relative resonance positions in the spectrum. KW - transition-potential method KW - X-ray absorption KW - spectroscopy KW - Delta-Kohn-Sham Y1 - 2020 U6 - https://doi.org/10.1002/jcc.26219 SN - 0192-8651 SN - 1096-987X VL - 41 IS - 19 SP - 1781 EP - 1789 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Belasri, Khadija A1 - Topal, Leila A1 - Heydenreich, Matthias A1 - Koch, Andreas A1 - Kleinpeter, Erich A1 - Fulop, Ferenc A1 - Szatmari, Istvan T1 - Synthesis and conformational analysis of naphthoxazine-fused phenanthrene derivatives JF - Molecules N2 - The synthesis of new phenanthr[9,10-e][1,3]oxazines was achieved by the direct coupling of 9-phenanthrol with cyclic imines in the modified aza-Friedel-Crafts reaction followed by the ring closure of the resulting bifunctional aminophenanthrols with formaldehyde. Aminophenanthrol-type Mannich bases were synthesised and transformed to phenanthr[9,10-e][1,3]oxazines via [4 + 2] cycloaddition. Detailed NMR structural analyses of the new polyheterocycles as well as conformational studies including Density Functional Theory (DFT) modelling were performed. The relative stability of ortho-quinone methides (o-QMs) was calculated, the geometries obtained were compared with the experimentally determined NMR structures, and thereby, the regioselectivity of the reactions has been assigned. KW - modified Mannich reaction KW - cyclic imines KW - [4+2] cycloaddition KW - NMR KW - spectroscopy KW - conformational analysis KW - DFT calculations Y1 - 2020 U6 - https://doi.org/10.3390/molecules25112524 SN - 1420-3049 VL - 25 IS - 11 PB - MDPI CY - Basel ER - TY - JOUR A1 - Qiu, Xunlin A1 - Benjamin, Aravindan Joseph A1 - Raman Venkatesan, Thulasinath A1 - Schmidt, Georg C. A1 - Soler, Ricardo Alonso Quintana A1 - Panicker, Pramul Muraleedhara A1 - Gerhard, Reimund A1 - Hübler, Arved Carl T1 - Dielectric and electroacoustic assessment of screen-printed piezoelectric polymer layers as flexible transducers BT - influence of the electrode material JF - IEEE transactions on dielectrics and electrical insulation N2 - Here, piezoelectric transducers consisting of a P(VDF-TrFE) layer with either silver or PEDOT:PSS screen-printed electrodes are studied. The influence of electrodes on the dielectric and electroacoustic properties are studied in dielectric-spectroscopy and ferroelectric-hysteresis measurements. Only when both the bottom and the top electrodes are made of silver, the typical dielectric relaxation of the P(VDF-TrFE) layer is clearly observed. When one or two of the electrodes are of PEDOT:PSS, a Debye-like relaxation is present. Compared with silver electrodes, PEDOT:PSS electrodes allow for moderate self-healing. Consequently, samples with bottom and top PEDOT:PSS electrodes can be poled to saturation, while samples with silver electrodes can hardly be poled to saturation due to destructive electric breakdown. Acoustic transducer measurements show that silver electrodes facilitate higher and broader frequency operation, while PEDOT:PSS electrodes bring slightly lower total harmonic distortion. Overall, the acoustic performance shows no significant deviations between differently electroded samples so that silver electrodes do not offer any advantages for the transducers studied here due to their much higher tendency for destructive electric breakdown. KW - poly(vinylidenefluoride-trifluoroethylene) P(VDF-TrFE) KW - dielectric KW - spectroscopy KW - ferroelectricity and piezoelectricity in polymers KW - screen KW - printing KW - printed electroacoustic thin-film transducers Y1 - 2020 U6 - https://doi.org/10.1109/TDEI.2020.008864 SN - 1070-9878 SN - 1558-4135 SN - 0018-9367 VL - 27 IS - 5 SP - 1683 EP - 1690 PB - Institute of Electrical and Electronics Engineers CY - New York, NY ER - TY - GEN A1 - Ellis, S. C. A1 - Bauer, S. A1 - Bacigalupo, C. A1 - Bland-Hawthorn, J. A1 - Bryant, J. J. A1 - Case, S. A1 - Content, R. A1 - Fechner, T. A1 - Giannone, D. A1 - Haynes, R. A1 - Hernandez, E. A1 - Horton, A. J. A1 - Klauser, U. A1 - Lawrence, J. S. A1 - Leon-Saval, S. G. A1 - Lindley, E. A1 - Löhmannsröben, Hans-Gerd A1 - Min, S. -S. A1 - Pai, N. A1 - Roth, M. A1 - Shortridge, K. A1 - Waller, L. A1 - Xavier, Pascal A1 - Zhelem, Ross T1 - PRAXIS: an OH suppression optimised near infrared spectrograph T2 - Ground-based and Airborne Instrumentation for Astronomy VII N2 - The problem of atmospheric emission from OH molecules is a long standing problem for near-infrared astronomy. PRAXIS is a unique spectrograph which is fed by fibres that remove the OH background and is optimised specifically to benefit from OH-Suppression. The OH suppression is achieved with fibre Bragg gratings, which were tested successfully on the GNOSIS instrument. PRAXIS uses the same fibre Bragg gratings as GNOSIS in its first implementation, and will exploit new, cheaper and more efficient, multicore fibre Bragg gratings in the second implementation. The OH lines are suppressed by a factor of similar to 1000, and the expected increase in the signal-to-noise in the interline regions compared to GNOSIS is a factor of similar to 9 with the GNOSIS gratings and a factor of similar to 17 with the new gratings. PRAXIS will enable the full exploitation of OH suppression for the first time, which was not achieved by GNOSIS (a retrofit to an existing instrument that was not OH-Suppression optimised) due to high thermal emission, low spectrograph transmission and detector noise. PRAXIS has extremely low thermal emission, through the cooling of all significantly emitting parts, including the fore-optics, the fibre Bragg gratings, a long length of fibre, and the fibre slit, and an optical design that minimises leaks of thermal emission from outside the spectrograph. PRAXIS has low detector noise through the use of a Hawaii-2RG detector, and a high throughput through a efficient VPH based spectrograph. PRAXIS will determine the absolute level of the interline continuum and enable observations of individual objects via an IFU. In this paper we give a status update and report on acceptance tests. KW - Near infrared KW - spectroscopy KW - OH suppression KW - astrophotonics KW - fibre Bragg gratings Y1 - 2018 SN - 978-1-5106-1958-6 U6 - https://doi.org/10.1117/12.2311898 SN - 0277-786X SN - 1996-756X VL - 10702 PB - SPIE-INT Soc Optical Engineering CY - Bellingham ER - TY - JOUR A1 - Laux, Eva-Maria A1 - Ermilova, Elena A1 - Pannwitz, Daniel A1 - Gibbons, Jessica A1 - Hölzel, Ralph A1 - Bier, Frank Fabian T1 - Dielectric Spectroscopy of Biomolecules up to 110 GHz JF - Frequenz N2 - Radio-frequency fields in the GHz range are increasingly applied in biotechnology and medicine. In order to fully exploit both their potential and their risks detailed information about the dielectric properties of biological material is needed. For this purpose a measuring system is presented that allows the acquisition of complex dielectric spectra over 4 frequency decade up to 110 GHz. Routines for calibration and for data evaluation according to physicochemical interaction models have been developed. The frequency dependent permittivity and dielectric loss of some proteins and nucleic acids, the main classes of biomolecules, and of their sub-units have been determined. Dielectric spectra are presented for the amino acid alanine, the proteins lysozyme and haemoglobin, the nucleotides AMP and ATP, and for the plasmid pET-21, which has been produced by bacterial culture. Characterisation of a variety of biomolecules is envisaged, as is the application to studies on protein structure and function. KW - dielectric KW - spectroscopy KW - permittivity KW - protein KW - DNA KW - amino acid KW - plasmid Y1 - 2018 U6 - https://doi.org/10.1515/freq-2018-0010 SN - 0016-1136 SN - 2191-6349 VL - 72 IS - 3-4 SP - 135 EP - 140 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Wolff, Martin A1 - Gast, Klaus A1 - Evers, Andreas A1 - Kurz, Michael A1 - Pfeiffer-Marek, Stefania A1 - Schüler, Anja A1 - Seckler, Robert A1 - Thalhammer, Anja T1 - A Conserved Hydrophobic Moiety and Helix-Helix Interactions Drive the Self-Assembly of the Incretin Analog Exendin-4 JF - Biomolecules N2 - Exendin-4 is a pharmaceutical peptide used in the control of insulin secretion. Structural information on exendin-4 and related peptides especially on the level of quaternary structure is scarce. We present the first published association equilibria of exendin-4 directly measured by static and dynamic light scattering. We show that exendin-4 oligomerization is pH dependent and that these oligomers are of low compactness. We relate our experimental results to a structural hypothesis to describe molecular details of exendin-4 oligomers. Discussion of the validity of this hypothesis is based on NMR, circular dichroism and fluorescence spectroscopy, and light scattering data on exendin-4 and a set of exendin-4 derived peptides. The essential forces driving oligomerization of exendin-4 are helix–helix interactions and interactions of a conserved hydrophobic moiety. Our structural hypothesis suggests that key interactions of exendin-4 monomers in the experimentally supported trimer take place between a defined helical segment and a hydrophobic triangle constituted by the Phe22 residues of the three monomeric subunits. Our data rationalize that Val19 might function as an anchor in the N-terminus of the interacting helix-region and that Trp25 is partially shielded in the oligomer by C-terminal amino acids of the same monomer. Our structural hypothesis suggests that the Trp25 residues do not interact with each other, but with C-terminal Pro residues of their own monomers. KW - biophysics KW - diabetes KW - peptides KW - oligomerization KW - conformational change KW - molecular modeling KW - static and dynamic light scattering KW - spectroscopy Y1 - 2021 U6 - https://doi.org/10.3390/biom11091305 SN - 2218-273X VL - 11 IS - 9 PB - MDPI CY - Basel ER -