We study rare events in soft matter and biomolecular systems, including folding of proteins, biomolecular isomerization and association, soft matter self-assembly and nucleation, and active matter transitions. In order to gain insight in such processes and make predictions, we conduct multiscale modeling simulations using rare event and coarse-graining techniques. In addition, we develop novel advanced simulation methods, including machine learning based techniques. The final aim is to predict biophysical and soft matter properties, to understand complex systems and design novel materials.
Our research focuses on the study of hydrodynamic flow in colloidal systems that have a close relation to biology, where physical modeling can give insights into biomedically relevant problems. Specifically, we are interested in the effect of nonlinear response of the fluid medium (viscoelasticity) on the motion of out-of-equilibrium particles and model swimmers therein, think bacteria moving through mucus. In addition, we study the effect of simple fluid flow on large numbers of colloids, e.g., colloidal gels, and the effects of electrokinetic flow on the transport of particles and ions through nanopores. We employ lattice Boltzmann, finite element methods, Stokesian dynamics, molecular dynamics, Monte Carlo, and a host of analytic techniques to tackle these problems.
Our research focuses on theory and computer simulations of soft condensed matter systems to study physical phenomena like phase transitions, glass and jamming transitions, gelation, and nucleation in bulk systems and systems subjected to external fields like sedimentation, electric fields, etc. We employ Monte Carlo, (event driven) Molecular and Brownian Dynamics simulations, Stochastic Rotational Dynamics simulations to include hydrodynamics, Umbrella and Forward flux sampling, and simulated annealing techniques to predict densest packings, candidate (crystal) structures and to determine the (non)-equilibrium phase behavior of colloids, nanoparticles, liquid crystals, etc.
We research the physical foundations of novel (often bio-inspired) materials that respond to their environment in interesting or useful ways. Using and developing numerical methods such as molecular dynamics, as well as analytical tools based in statistical physics, we study the (two-way!) interplay between mechanical forces and structural properties of novel responsive materials.
The Wageningen Soft Matter group works on a range of diverse topics, in which macromolecules generally play an important role. Specific topics include: foams, emulsion and ionic liquids; dense particle systems; biomimetic materials; molecular modelling; proteins and engineered protein polymers; self-assembly of micelles, membranes and vesicles; hydrogels. We aim at analysing soft materials from a physics point of view and manipulating them using chemical tools and expertise.
We study concentrated colloidal dispersions subjected to external fields such as gravity, an electric field, or a shear flow. This way we can manipulate the particles to assemble into new structures, to undergo (non-equilibrium) phase transitions, or to form patterns. The 3-dimensional structure and dynamics are studied mainly using confocal microscopy, but also with scattering techniques and rheology. For these experiments new colloidal particles with anisotropic shapes or interactions or with a composite core-shell structure are also developed.
We are interested in soft matter systems that are inherently out of thermodynamic equilibrium, ranging from non-crystalline polymers and glasses to active and living matter. We employ a combination of statistical-mechanical theory, analytical modeling, and computer simulations to study the structural, dynamical, and mechanical response properties of such materials. The aim is two-fold: firstly, we seek to gain new fundamental insight into the physics of soft and living matter, focusing mainly on the relation between microstructure and emergent dynamics; secondly, we aim to develop new theoretical tools that will ultimately allow us to rationally design, control, and optimize functional materials with adaptive, life-like, and "smart" properties.
We are interested in the mechanisms that govern the spontaneous formation of ordered structures from colloidal building blocks. Inspired by the rich complexity in biology, we develop and study new colloidal model systems in which both the geometry of the colloids and the orientation dependent interactions between them can be tuned. While emphasis is on experiments, theory plays an important role in our approach.
The soft condensed matter group of Daniela Kraft is interested in the physics and self-organization of soft matter systems. Topics include the rational design of anisotropic and patchy particles for use as model systems and self-assembly, particle-covered emulsions and virus particles.
We work on the design, synthesis and characterization of colloidal particles for the self-assembly of novel materials. One of the main research focus of the group is the use of magnetic interactions to induce, control and study the rational assembly of colloids into materials with specific and adaptable mechanical and optical properties. Other topics include active matter, defect dynamics, drug delivery and diagnostics.
We investigate soft condensed matter at the micron scale - crystallization and phase separations, solid and liquid-like behavior, elastic and plastic properties. Using three-dimensional microscopic imaging and light scattering we bridge length scales from the particle scale to macroscopic lengths, thereby linking the microscopic behavior of these materials to their macroscopic properties.
We study and develop new responsive colloidal and polymeric systems. A major aim is to identify the mechanisms for catastrophic macroscopic phenomena such as fracture, melting and phase inversion at which microscopic structures, stresses and thermal fluctuations all become of significance. We also work on manipulating this interplay at the microscopic level to create new materials with enhanced functionality.
In the Laboratory of Physical Chemistry we study the i) self-organization of colloids and polymers, ii) phase behaviour (and dynamics) of colloidal and colloid-polymer mixtures and iii) polymers & colloids at surfaces. For theme i applications involve the controlled encapsulation of compounds that need protection and/or need to be released at a desired rate. Topic ii aims at gaining a better understanding of the phase stability and dynamics in complex mixtures of colloids and polymers and bringing the knowledge towards mixtures in which the particles have realistic interactions (such as charges, soft repulsions). Applications involve understanding phase stability of complex mixtures such as food and (drying) paint. Theme iii involves the development of advanced (modified) surfaces for anti-(bio)fouling, controlled absorption/release and specific (bio)adhesion using tuned chemistry and topography as well as modifying surfaces to understand wettability, swelling, oil/water interaction(s).
Our research has a focus on theoretical and numerical analyses of thermodynamics, structure, and (hydro)dynamics of a variety of liquids and soft matter systems on the basis of statistical physics, classical (dynamic) density functional theory and transport theory combined with numerical finite-element calculations. Systems of interest include (i) electrolytes (ionic liquids, organic solvents, supercapacitors, electro-kinetics, blue energy, enhanced oil recovery), (ii) self-assembly in colloidal dispersions (bulk phase behaviour, crystals and liquid crystals of odd-shaped particles with flexibility/chirality/biaxiality), (iii) active matter (search for a thermodynamic formalism, self-propulsion mechanisms, swim efficiency), and (iv) interfacial phenomena (adsorption, wetting, capillarity, 2D self-assembly). We focus on fundamental questions but also study the underlying physics of devices and their applications where possible. We intensively collaborate with computer simulation and experimental groups.
We use and develop experimental tools to study the structure, dynamics and rheology of soft materials, thereby revealing the physical mechanisms that govern their behavior. Current topics include the mechanics of cells and soft microgel particle systems, the use of microfluidics to control and study soft matter, colloids with anisotropic interactions, and the development of new mechanical probes.