Condensed Matter and Biophysics Experiment

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The experimental condensed-matter group is focused on elucidating the complex relationship between materials science and biology. The entire experimental group are members of the Brandeis Materials Research Science and Engineering Center in which interdisciplinary teams elucidate the role that material properties play in the structure and function of cells and exploit this knowledge to create new categories of materials. In one approach, biological structures are used for “bottom-up” assembly of novel biomaterials with unique properties. In a complementary “top-down” approach, materials properties of functioning biological structures are examined in order to determine how they give rise to specific biological function. From a techniques perspective there is a strong emphasis on various microscopy methods and microfludic technology. There are close interactions with the condensed-matter theory group in the physics department as well as various faculty from departments of chemistrybiochemistry and biology.

The focus of Professor Zvonimir Dogic and his group lies in elucidating rules that govern self-assembly of materials, with a particular emphasis being placed on the role the particle's shape and chirality play in these assembly processes.  The goal is to create very simple model systems in which precise control is possible over all the relevant parameters.  This enables a rigorous and detailed comparison with theoretical predictions.  To accomplish our goals, in addition to a host of experimental techniques including optical microscopy, laser tweezers, single molecules techniques, we also utilize theoretical statistical mechanics, computer simulations, biochemistry, various protein purification techniques and molecular cloning. Zvonimir Dogic is also a member of the Complex Fluid Group at Brandeis.

Professor Seth Fraden and his group seek to understand the relation between interparticle interactions and phase transitions in colloidal suspensions such as genetically engineered viruses, latex, proteins and polymers. Combining experiment, computer simulation and theory, Fraden examines the role of entropy in driving disorder-to-order transitions.

One application is in nanotechnology, where entropy-driven assembly principles are being developed to construct novel layered materials. Other major objectives are to understand the physics of protein crystallization and the development of "lab on a chip" technology, which incorporates microfluidics to build high throughput devices for biotechnology.

Professor Robert Meyer studies complex fluid systems, including liquid crystals, colloidal suspension and polymers, all systems with a degree of internal structure and order, but not the perfectly regular order of crystals. They attempt to understand these systems in terms of both their fundamental microscopic ordering and their macroscopic phenomenology, which is very rich in nonlinear phenomena of all kinds.

This latter subject has led to new research projects in chaotic dynamics in both dissipative hydrodynamic systems and electronic circuits. Experimental techniques include X-ray and light scattering, optical microscopy with computerized image analysis and simulations. Theory is developed where appropriate. There are close collaborations with other members of the complex fluids group.

Professor Azadeh Samadani and her lab places a major emphasis in combining quantitative experimental methods with theoretical and computational approaches to study biological questions at the systems level. Her research interests include understanding directional sensing mechanisms in eukaryotic cells, nongenetic individuality and its effects on the fitness of a population, noise in biological systems, swimming microorganisms, population dynamics, pattern formation, predator-prey interaction, complex materials and microfluidic devices.