Prof. Dr. Joachim Dzubiella
Profil
Forschungsthemen8
Modellierung von Zelladhaesion mithilfe Weicher-Materie Modellsysteme
Quelle ↗Förderer: Alexander von Humboldt-Stiftung Zeitraum: 05/2013 - 04/2015 Projektleitung: Prof. Dr. Joachim Dzubiella
Molekulardynamische Simulationsstudie über die Lamination von Polycarbonat
Quelle ↗Zeitraum: 04/2016 - 09/2016 Projektleitung: Prof. Dr. Joachim Dzubiella
NW: Stabilitaet halophiler Proteine II
Quelle ↗Förderer: DFG Nachwuchsgruppe Zeitraum: 10/2011 - 07/2013 Projektleitung: Prof. Dr. Joachim Dzubiella
SFB 951/1: HIOS - Exploring molecular-scale structure formation of HIOS by all-atom molecular dynamics computer simulations (TP A1)
Quelle ↗409-01 · Theoretische InformatikFörderer: DFG Sonderforschungsbereich Zeitraum: 07/2011 - 06/2015 Projektleitung: Prof. Dr. Joachim Dzubiella
SFB 951/2: Untersuchung von Strukturbildung in HIOS auf molekularen Skalen mit Hilfe von atomar aufgelösten molekulardynamischen Computersimulationen (TP A01)
Quelle ↗Förderer: DFG Sonderforschungsbereich Zeitraum: 07/2015 - 06/2019 Projektleitung: Prof. Dr. Joachim Dzubiella
Stabilität halophiler Proteine: Wettbewerb zwischen Hydrophober und elektrostatischer Solvation
Quelle ↗Förderer: DFG Nachwuchsgruppe Zeitraum: 10/2011 - 07/2013 Projektleitung: Prof. Dr. Joachim Dzubiella
Theoretische Untersuchung der Rolle von Wasser in hydrophober Schluessel-Schloss Paarungskinetik
Quelle ↗Förderer: DFG Sachbeihilfe Zeitraum: 02/2014 - 01/2017 Projektleitung: Prof. Dr. Joachim Dzubiella
Theoretische Untersuchung elektrostatischer Effekte auf die kritische Loesungsmitteltemperatur von thermosensitiven, statistischen Copolymeren
Quelle ↗Förderer: DFG Sachbeihilfe Zeitraum: 10/2013 - 04/2017 Projektleitung: Prof. Dr. Joachim Dzubiella
Mögliche Industrie-Partner10
Stand: 26.4.2026, 19:48:44 (Top-K=20, Min-Cosine=0.4)
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Publikationen25
Top 25 nach Zitationen — Quelle: OpenAlex (BAAI/bge-m3 embedded für Matching).
Chemical Society Reviews · 1080 Zitationen · DOI
Catalysis by metallic nanoparticles is certainly among the most intensely studied problems in modern nanoscience. However, reliable tests for catalytic performance of such nanoparticles are often poorly defined, which makes comparison and benchmarking rather difficult. We tackle in this tutorial review a subset of well-studied reactions that take place in aqueous phase and for which a comprehensive kinetic analysis is available. Two of these catalytic model reactions are under consideration here, namely the reduction of (i) p-nitrophenol and (ii) hexacyanoferrate (iii), both by borohydride ions. Both reactions take place at the surface of noble metal nanoparticles at room temperature and can be accurately monitored by UV-vis spectroscopy. Moreover, the total surface area of the nanoparticles in solution can be known with high precision and thus can be directly used for the kinetic analysis. Hence, these model reactions represent cases of heterogeneous catalysis that can be modelled with the accuracy typically available for homogeneous catalysis. Both model reactions allow us to discuss a number of important concepts and questions, namely the dependence of catalytic activity on the size of the nanoparticles, electrochemistry of nanoparticles, surface restructuring, the use of carrier systems and the role of diffusion control.
Angewandte Chemie International Edition · 729 Zitationen · DOI
Protein adsorption is considered to be the most important factor of the interaction between polymeric biomaterials and body fluids or tissues. Water-mediated hydrophobic and hydration forces as well as electrostatic interactions are believed to be the major factors of protein adsorption. A systematic analysis of various monolayer systems has resulted in general guidelines, the so-called "Whitesides rules". These concepts have been successfully applied for designing various protein-resistant surfaces and are being studied to expand the understanding of protein-material interactions beyond existing limitations. Theories on the mechanisms of protein adsorption are constantly being improved due to the fast-developing analytical technologies. This Review is aimed at improving these empirical guidelines with regard to present theoretical and analytical advances. Current analytical methods to test mechanistic hypotheses and theories of protein-surface interactions will be discussed. Special focus will be given to state-of-the-art bioinert and biospecific coatings and their applications in biomedicine.
The Journal of Physical Chemistry B · 667 Zitationen · DOI
Ions differ in their ability to salt out proteins from solution as expressed in the lyotropic or Hofmeister series of cations and anions. Since its first formulation in 1888, this series has been invoked in a plethora of effects, going beyond the original salting out/salting in idea to include enzyme activities and the crystallization of proteins, as well as to processes not involving proteins like ion exchange, the surface tension of electrolytes, or bubble coalescence. Although it has been clear that the Hofmeister series is intimately connected to ion hydration in homogeneous and heterogeneous environments and to ion pairing, its molecular origin has not been fully understood. This situation could have been summarized as follows: Many chemists used the Hofmeister series as a mantra to put a label on ion-specific behavior in various environments, rather than to reach a molecular level understanding and, consequently, an ability to predict a particular effect of a given salt ion on proteins in solutions. In this Feature Article we show that the cationic and anionic Hofmeister series can now be rationalized primarily in terms of specific interactions of salt ions with the backbone and charged side chain groups at the protein surface in solution. At the same time, we demonstrate the limitations of separating Hofmeister effects into independent cationic and anionic contributions due to the electroneutrality condition, as well as specific ion pairing, leading to interactions of ions of opposite polarity. Finally, we outline the route beyond Hofmeister chemistry in the direction of understanding specific roles of ions in various biological functionalities, where generic Hofmeister-type interactions can be complemented or even overruled by particular steric arrangements in various ion binding sites.
Nature Communications · 511 Zitationen · DOI
Angewandte Chemie International Edition · 401 Zitationen · DOI
Selectivity in nanoreactors: A hybrid yolk–shell nanostructure that contains gold nanoparticles in the core and thermosensitive microgel poly(N-isopropylacrylamide) (PNIPA) as shell is presented. The catalytic selectivity of Au-PNIPA nanoparticles for the reduction of hydrophilic 4-nitrophenol and more hydrophobic nitrobenzene with NaBH4 can be tuned through the volume transition of PNIPA shell (see picture). Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics · 225 Zitationen · DOI
The influence of an external field on a binary colloidal mixture performing Brownian dynamics in a solvent is investigated by nonequilibrium computer simulations and simple theory. In our model, one half of the particles are pushed into the field direction while the other half of them are pulled into the opposite direction. For increasing field strength, we show that the system undergoes a nonequilibrium phase transition from a disordered state to a state characterized by lane formation parallel to the field direction. The lanes are formed by the same kind of particles moving collectively with the field. Lane formation accelerates particle transport parallel to the field direction but suppresses massively transport perpendicular to the field. We further show that lane formation also occurs in a time-dependent oscillatory field. If the frequency of the external field exceeds a critical value, however, the system exhibits a transition back to the disordered state. Our results can be experimentally verified in binary colloidal suspensions exposed to external fields under nonequilibrium conditions.
The Journal of Chemical Physics · 188 Zitationen · DOI
The permeation of hydrophobic, cylindrical nanopores by water molecules and ions is investigated under equilibrium and out-of-equilibrium conditions by extensive molecular-dynamics simulations. Neglecting the chemical structure of the confining pore surface, we focus on the effects of pore radius and electric field on permeation. The simulations confirm the intermittent filling of the pore by water, reported earlier under equilibrium conditions for pore radii larger than a critical radius R(c). Below this radius, water can still permeate the pore under the action of a strong electric field generated by an ion concentration imbalance at both ends of the pore embedded in a structureless membrane. The water driven into the channel undergoes considerable electrostriction characterized by a mean density up to twice the bulk density and by a dramatic drop in dielectric permittivity which can be traced back to a considerable distortion of the hydrogen-bond network inside the pore. The free-energy barrier to ion permeation is estimated by a variant of umbrella sampling for Na(+), K(+), Ca(2+), and Cl(-) ions, and correlates well with known solvation free energies in bulk water. Starting from an initial imbalance in ion concentration, equilibrium is gradually restored by successive ion passages through the water-filled pore. At each passage the electric field across the pore drops, reducing the initial electrostriction, until the pore, of radius less than R(c), closes to water and hence to ion transport, thus providing a possible mechanism for voltage-dependent gating of hydrophobic pores.
Physical Review Letters · 166 Zitationen · DOI
An implicit solvent model is presented that couples hydrophobic, dispersion, and electrostatic solvation energies by minimizing the system Gibbs free energy with respect to the solvent volume exclusion function. The solvent accessible surface is the output of the theory. The method is illustrated with the solvation of simple solutes on different length scales and captures the sensitivity of hydration to the particular form of the solute-solvent interactions in agreement with recent computer simulations.
Advanced Materials · 159 Zitationen · DOI
Ultrasensitive polymer actuators are prepared, which can sense a very small amount (0.25 mol%) of acetone solvent in water, discriminate butanol isomers, and perform cooperative actuation.
Physical Review Letters · 136 Zitationen · DOI
We investigate sedimentation of model hard-sphere-like colloidal dispersions confined in horizontal capillaries using laser scanning confocal microscopy, dynamical density functional theory, and Brownian dynamics computer simulations. For homogenized initial states we obtain quantitative agreement of the results from the respective approaches for the time evolution of the one-body density distribution and the osmotic pressure on the walls. We demonstrate that single-particle information can be obtained experimentally in systems that were initialized further out of equilibrium such that complex lateral patterns form.
Physical Review Letters · 125 Zitationen · DOI
The concept of effective depletion forces between two fixed big colloidal particles in a bath of small particles is generalized to a nonequilibrium situation where the bath of small Brownian particles is flowing around the big particles with a prescribed velocity. In striking contrast to the equilibrium case, the nonequilibrium forces violate Newton's third law; they are nonconservative and strongly anisotropic, featuring both strong attractive and repulsive domains.
The Journal of Chemical Physics · 123 Zitationen · DOI
The structure of aqueous LiCl, NaCl, KCl, CsCl, KF, and NaI solutions is calculated by molecular dynamics (MD) simulations of the frequently employed Dang force-field in SPC/E water. By using liquid state theory, we integrate the structure to obtain the electrolytes' osmotic coefficient phi and systematically investigate force-field quality and structural consequences to ion-specific bulk thermodynamics. The osmotic coefficients phi(chi) calculated from the exact compressibility route for the cation-Cl(-) force-fields match experiments for concentrations rho approximately < 2M, while NaI and KF parameters fail. Comparison of phi(chi) with phi(v) from the virial route, which relies on the pair potential approximation, shows that many-body effects become important for all salts above rho approximately 0.5M. They can be efficiently corrected, however, by employing a salt-type and rho-dependent dielectric constant epsilon(rho), generalizing previous observations on NaCl only. For physiological concentrations, rho approximately < 0.5M, the specific osmotic behavior is found to be determined by the short-ranged cation-anion pair potential only and is strongly related to the second virial coefficient of the latter. Presented methods and findings, based on simple integrations over the electrolyte structure, enable efficient MD force-field refinement by direct benchmarking to the sensitive electrolyte thermodynamics, instead to noncollective, single ion properties.
The Journal of Physical Chemistry B · 118 Zitationen · DOI
Affinities of alkali cations and halide anions for the peptide group were quantified using molecular dynamics simulations of aqueous solutions of N-methylacetamide using both nonpolarizable and polarizable force fields. Potassium and, more strongly, sodium exhibit an affinity for the carbonyl oxygen of the amide group, while none of the halide anions shows any appreciable attraction for the amide hydrogen. Heavier halides, however, interact with the hydrophobic methyl groups of N-methylacetamide. Using the present results for a model of the peptide bond we predict that the destabilizing effect of weakly hydrated Hofmeister ions, such as bromide or iodide, is not due to direct interactions with the backbone but rather due to attraction to hydrophobic regions of the protein.
Soft Matter · 113 Zitationen · DOI
We present a thermodynamic study of the adsorption of lysozyme on a negatively charged core–shell microgel at pH 7.2. The carrier particles consist of a polystyrene core onto which a charged poly(N-isopropylacrylamide-co-acrylic acid) network is attached. Isothermal titration calorimetry (ITC) is used to investigate the temperature and salt dependence of lysozyme binding. Our ITC analysis unequivocally shows that the adsorption of lysozyme onto the charged gel is driven by entropy. The addition of salt strongly decreases the binding affinity, indicating significant electrostatic contributions to the adsorption process. However, at high salt concentrations, substantial protein binding with unaltered entropies is still observed pointing to large contributions from hydrophobic interactions. Furthermore, the calorimetric analysis suggests that protonation of lysozyme takes place upon binding. This is directly shown by analysis of the enzymatic activity of adsorbed lysozyme. It was found that the activity is enhanced about ∼3.5 times, indicating that lysozyme has taken up approximately one proton when entering the gel. The entire set of data demonstrates that core–shell microgels present “smart” colloidal carriers for lysozyme that enhance its activity.
The Journal of Physical Chemistry B · 109 Zitationen · DOI
Cosolvent effects on protein or polymer collapse transitions are typically discussed in terms of a two-state free energy change that is strictly linear in cosolute concentration. Here we investigate in detail the nonlinear thermodynamic changes of the collapse transition occurring at the lower critical solution temperature (LCST) of the role-model polymer poly(N-isopropylacrylamide) [PNIPAM] induced by Hofmeister salts. First, we establish an equation, based on the second-order expansion of the two-state free energy in concentration and temperature space, which excellently fits the experimental LCST curves and enables us to directly extract the corresponding thermodynamic parameters. Linear free energy changes, grounded on generic excluded-volume mechanisms, are indeed found for strongly hydrated kosmotropes. In contrast, for weakly hydrated chaotropes, we find significant nonlinear changes related to higher order thermodynamic derivatives of the preferential interaction parameter between salts and polymer. The observed non-monotonic behavior of the LCST can then be understood from a not yet recognized sign change of the preferential interaction parameter with salt concentration. Finally, we find that solute partitioning models can possibly predict the linear free energy changes for the kosmotropes, but fail for chaotropes. Our findings cast strong doubt on their general applicability to protein unfolding transitions induced by chaotropes.
Macromolecules · 108 Zitationen · DOI
The collapse and swelling behavior of a generic homopolymer is studied using implicit-solvent, explicit-cosolvent Langevin dynamics computer simulations for varying interaction strengths. The systematic investigation reveals that polymer swelling is maximal if both monomer–monomer and monomer–cosolute interactions are weakly attractive. In the most swollen state the cosolute density inside the coil is remarkably bulk-like and homogeneous. Highly attractive monomer–cosolute interactions, however, are found to induce a collapse of the chain, which, in contrast to the collapsed case induced by purely repulsive cosolvents, exhibits a considerably enhanced cosolute density within the globule. Thus, collapsed states, although appearing similar on a first glance, may result from very different mechanisms with distinct final structural and thermodynamic properties. Two theoretical models, the first based on an effective one-component description where the cosolutes have been integrated out and, second, a fully two-component Flory–de Gennes like model, support the simulation findings above and serve for interpretation. In particular, the picture is supported that collapse in highly attractive cosolvents is driven by cross-linking-like bridging effects, while the ratio of attraction range to cosolute size plays a critical role behind this mechanism. Only if polymer–cosolute interactions are not too short-ranged, swelling effects should be observable. Our findings may be important for the interpretation of the effects of cosolutes on polymer and protein conformational structure, in particular for highly attractive interaction combinations, such as provided by urea, GdmCl, NaI, or NaClO4 near peptide-like moieties.
Polymer · 107 Zitationen · DOI
We review recent work on the adsorption of proteins on two types of well-defined colloidal particles, namely on i) spherical polyelectrolytes that consist of a solid core onto which long chains of a polyelectrolyte are attached, and ii) core–shell microgels that have a shell of crosslinked poly(N-isopropylacrylamide) (pNiPAm) chains. The latter system may bear charges as well by copolymerization with acrylic acid. The surface layers of both systems that have a thickness of ca. 50 nm create a microenvironment in which the salt concentration and the pH differ from the outside solution. Adsorption of various proteins to these particles is monitored by various methods including calorimetry, fluorescence spectroscopy and small-angle X-ray scattering. These investigations also include studies of the kinetics of adsorption. The secondary structure of the proteins can be analyzed in these systems by FT-IR spectroscopy. Their tertiary structure can be checked by measurements of the enzymatic activity. In some cases the adsorbed enzymes exhibit an even higher activity as compared to the free protein in solution. We review the application of these techniques to monitor adsorption of proteins to these particles. All data demonstrate that both types of particles present model systems that help us to explore the main driving forces of protein adsorption.
Proceedings of the National Academy of Sciences · 98 Zitationen · DOI
Water plays a crucial part in virtually all protein-ligand binding processes in and out of equilibrium. Here, we investigate the role of water in the binding kinetics of a ligand to a prototypical hydrophobic pocket by explicit-water molecular dynamics (MD) simulations and implicit diffusional approaches. The concave pocket in the unbound state exhibits wet/dry hydration oscillations whose magnitude and time scale are significantly amplified by the approaching ligand. In turn, the ligand's stochastic motion intimately couples to the slow hydration fluctuations, leading to a sixfold-enhanced friction in the vicinity of the pocket entrance. The increased friction considerably decelerates association in the otherwise barrierless system, indicating the importance of molecular-scale hydrodynamic effects in cavity-ligand binding arising due to capillary fluctuations. We derive and analyze the diffusivity profile and show that the mean first passage time distribution from the MD simulation can be accurately reproduced by a standard Brownian dynamics simulation if the appropriate position-dependent friction profile is included. However, long-time decays in the water-ligand (random) force autocorrelation demonstrate violation of the Markovian assumption, challenging standard diffusive approaches for rate prediction. Remarkably, the static friction profile derived from the force correlations strongly resembles the profile derived on the Markovian assumption apart from a simple shift in space, which can be rationalized by a time-space retardation in the ligand's downhill dynamics toward the pocket. The observed spatiotemporal hydrodynamic coupling may be of biological importance providing the time needed for conformational receptor-ligand adjustments, typical of the induced-fit paradigm.
Journal of the American Chemical Society · 95 Zitationen · DOI
Frictional effects due to the chain itself, rather than the solvent, may have a significant effect on protein dynamics. Experimentally, such "internal friction" has been investigated by studying folding or binding kinetics at varying solvent viscosity; however, the molecular origin of these effects is hard to pinpoint. We consider the kinetics of disordered glycine-serine and α-helix forming alanine peptides and a coarse-grained protein folding model in explicit-solvent molecular dynamics simulations. By varying the solvent mass over more than two orders of magnitude, we alter only the solvent viscosity and not the folding free energy. Folding dynamics at the near-vanishing solvent viscosities accessible by this approach suggests that solvent and internal friction effects are intrinsically entangled. This finding is rationalized by calculation of the polymer end-to-end distance dynamics from a Rouse model that includes internal friction. An analysis of the friction profile along different reaction coordinates, extracted from the simulation data, demonstrates that internal as well as solvent friction varies substantially along the folding pathways and furthermore suggests a connection between friction and the formation of hydrogen bonds upon folding.
The Journal of Physical Chemistry B · 95 Zitationen · DOI
A mean-field approach to the electrostatics for solutes in electrolyte solution is revisited and rigorously justified. In this approach, an electrostatic free energy functional is constructed that depends solely on the local ionic concentrations. The unique set of such concentrations that minimize this free energy are given by the usual Boltzmann distributions through the electrostatic potential which is determined by the Poisson-Boltzmann equation. This approach is then applied to the variational implicit solvent description of the solvation of molecules [Dzubiella, Swanson, McCammon, Phys. Rev. Lett. 2006, 96, 087802; J. Chem. Phys. 2006, 124, 084905]. Care is taken for the singularities of the potential generated by the solute point charges. The variation of the electrostatic free energy with respect to the location change of solute-solvent interfaces, that is, dielectric boundaries, is derived. Such a variation gives rise to the normal component of the effective surface force per unit surface area that is shown to be attractive to the fixed point charges in the solutes. Two examples of applications are given to validate the analytical results. The first one is a one-dimensional model system resembling, for example, a charged solute or cavity in a one-dimensional channel. The second one, which is of its own interest, is the electrostatic free energy of a charged spherical solute immersed in an ionic solution. An analytical formula is derived for the Debye-Hückel approximation of the free energy, extending the classical Born's formula to one that includes ionic concentrations. Variations of the nonlinear Poisson-Boltzmann free energy are also obtained.
Journal of the American Chemical Society · 93 Zitationen · DOI
The structure of a single alanine-based Ace-AEAAAKEAAAKA-Nme peptide in explicit aqueous electrolyte solutions (NaCl, KCl, NaI, and KF) at large salt concentrations (3-4 M) is investigated using approximately 1 mus molecular dynamics (MD) computer simulations. The peptide displays 71% alpha-helical structure without salt and destabilizes with the addition of NaCl in agreement with experiments of a somewhat longer version. It is mainly stabilized by direct and indirect (" i + 4")EK salt bridges between the Lys and Glu side chains and a concomitant backbone shielding mechanism. NaI is found to be a stronger denaturant than NaCl, while the potassium salts hardly show influence. Investigation of the molecular structures reveals that consistent with recent experiments Na (+) has a much stronger affinity to side chain carboxylates and backbone carbonyls than K (+), thereby weakening salt bridges and secondary structure hydrogen bonds. At the same time, the large I (-) has a considerable affinity to the nonpolar alanine in line with recent observations of a large propensity of I (-) to adsorb to simple hydrophobes, and thereby "assists" Na (+) in its destabilizing action. In the denatured states of the peptide, novel long-lived (10-20 ns) "loop" configurations are observed in which single Na (+) ions and water molecules are hydrogen-bonded to multiple backbone carbonyls. In an attempt to analyze the denaturation behavior within the preferential interaction formalism, we find indeed that for the strongest denaturant, NaI, the protein is least hydrated. Additionally, a possible indication for protein denaturation might be a preferential solvation of the peptide backbone by the destabilizing cosolute (sodium). The mechanisms found in this work may be of general importance to understand salt effects on protein secondary structure stability.
Physical Review E · 90 Zitationen · DOI
Recently it has been shown that a strongly interacting colloidal mixture consisting of oppositely driven particles undergoes a nonequilibrium transition towards lane formation provided the driving strength exceeds a threshold value. We predict here a reentrance effect in lane formation: for fixed high driving force and increasing particle densities, there is first a transition towards lane formation which is followed by another transition back to a state with no lanes. Our result is obtained both by Brownian dynamics computer simulations and by a phenomenological dynamical density functional theory.
Journal of Physics Condensed Matter · 90 Zitationen · DOI
Using monomer-resolved Molecular Dynamics simulations and theoretical arguments based on the radial dependence of the osmotic pressure in the interior of a star, we systematically investigate the effective interactions between hard, colloidal particles and star polymers in a good solvent. The relevant parameters are the size ratio q between the stars and the colloids, as well as the number of polymeric arms f (functionality) attached to the common center of the star. By covering a wide range of q's ranging from zero (star against a flat wall) up to about 0.75, we establish analytical forms for the star-colloid interaction which are in excellent agreement with simulation results. A modified expression for the star-star interaction for low functionalities, f < 10 is also introduced.
Physical Review Letters · 83 Zitationen · DOI
We report on a combined atomistic molecular dynamics simulation and implicit solvent analysis of a generic hydrophobic pocket-ligand (host-guest) system. The approaching ligand induces complex wetting-dewetting transitions in the weakly solvated pocket. The transitions lead to bimodal solvent fluctuations which govern magnitude and range of the pocket-ligand attraction. A recently developed implicit water model, based on the minimization of a geometric functional, captures the sensitive aqueous interface response to the concave-convex pocket-ligand configuration semiquantitatively.
ACS Catalysis · 78 Zitationen · DOI
We describe a general theory for surface-catalyzed <i>bimolecular</i> reactions in responsive nanoreactors, catalytically active nanoparticles coated by a stimuli-responsive "gating" shell, whose permeability controls the activity of the process. We address two archetypal scenarios encountered in this system: the first, where two species diffusing from a bulk solution react at the catalyst's surface, and the second, where only one of the reactants diffuses from the bulk while the other is produced at the nanoparticle surface, e.g., by light conversion. We find that in both scenarios the total catalytic rate has the same mathematical structure, once diffusion rates are properly redefined. Moreover, the diffusional fluxes of the different reactants are strongly <i>coupled</i>, providing a behavior richer than that arising in unimolecular reactions. We also show that, in stark contrast to bulk reactions, the identification of a limiting reactant is not simply determined by the relative bulk concentrations but is controlled by the nanoreactor shell permeability. Finally, we describe an application of our theory by analyzing experimental data on the reaction between hexacyanoferrate(III) and borohydride ions in responsive hydrogel-based core-shell nanoreactors.
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Identität, Organisation und Kontakt aus HU-FIS.
- Name
- Prof. Dr. Joachim Dzubiella
- Titel
- Prof. Dr.
- Fakultät
- Mathematisch-Naturwissenschaftliche Fakultät
- Institut
- Institut für Physik
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- +49 30 2093-66373
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