Dusan Bratko
 |
Professor |
Professional preparation
Ph.D., University of Ljubljana , SIovenia
Senior Fulbright Scholar: SUNY at Stony Brook, N.Y.
Research interests
Our research in solution theories is directed toward understanding and control of the behavior of colloidal, biopolymeric and electrolyte systems relevant to biophysics and chemical engineering. We have been developing and applying analytic methods and advanced computational techniques based on principles of statistical mechanics. These include molecular and mesoscopic simulations, integral equation theory of liquids, and field-theoretic methods for studies of soft matter and disordered materials. The goal is to explain microscopic mechanisms behind observed macroscopic behaviors in order to predict new designs or improved conditions optimizing biological function or pragmatic performance of the material.
Our work is often synergistic with experimental groups in respective fields. Systems we have studied include solutions of synthetic and biological polyelectrolytes such as DNA, surfactant self-assemblies, liquid and quenched ionic media and protein solutions. This research has helped elucidate several crucial aspects of solution electrostatics and solvation phenomena that affect the structure and phase behavior of colloidal solutions, including the important role of ion-ion correlations in intercolloidal attraction.
The ability to control or reverse protein aggregation is vital to numerous technological processes in protein solutions and may be the key to prevention of a number of serious diseases. Complementing collaborative experimental work, we have been performing computational studies of molecular mechanisms involved in different stages of aggregation as a competitive process to protein folding.
In recent years, we have been concerned with modeling of interfacial liquids under the influence of confining surfaces, co-solutes, and applied external field. These efforts advance our understanding of solvation forces, and ability to tune materials’ surface thermodynamics for new applications.
Specific salt effects, crucial to solution properties of proteins and other bio-macromolecules are analyzed by a combination of molecular simulations and analytic integral equation approaches. We are extending these studies to solutions of nanoparticles with ionic ingredients. In view of close relation with physics of ionic colloids, our studies of protein solutions also impact several topics in colloidal theory, including solvation and confinement effects, ion-specificity and multipolar electrostatic interactions.
Publications
Bratko, D.; Daub, C. D.; Luzar, A., Water-mediated ordering of nanoparticles in an electric field, Faraday Discussions 2009, 141, 55-66.
Deniz, V.; Bostrom, M.; Bratko, D.; Tavares, F. W.; Ninham, B. W., Specific ion effects: Interaction between nanoparticles in electrolyte solutions. Colloids and Surfaces A-Physicochemical and Engineering Aspects 2008, 319, 98-102.
Bratko, D.; Daub, C. D.; Luzar, A., Field-exposed water in a nanopore: liquid or vapour? Physical Chemistry Chemical Physics 2008, 10, 6807-6813.
Bratko, D.; Luzar, A., Attractive surface force in the presence of dissolved gas: A molecular approach. Langmuir 2008, 24, 1247-1253.
Cellmer, T.; Bratko, D.; Prausnitz, J. M.; Blanch, H. W., Protein aggregation in silico. Trends in Biotechnology 2007, 25, 254-261.
Daub, C. D.; Bratko, D.; Leung, K.; Luzar, A., Electrowetting at the nanoscale. Journal of Physical Chemistry C 2007, 111, 505-509.
Bratko, D.; Cellmer, T.; Prausnitz, J. M.; Blanch, H. W., Molecular simulation of protein aggregation. Biotechnology and Bioengineering 2007, 96, 1-8.
Bratko, D.; Daub, C. D.; Leung, K.; Luzar, A., Effect of field direction on electrowetting in a nanopore. Journal of The American Chemical Society 2007, 129, 2504-2510.
Bostroem, M., Tavares, F.W., Bratko, D.; Ninham, B.W., Ion-Specific Interactions between Pairs of Nanometer Sized Particles in Aqueous Solutions, Progress in Colloid and Polymer Science 2006, 133, 74-77.
Bratko, D.; Cellmer, T.; Prausnitz, J. M.; Blanch, H. W., Effect of single-point sequence alterations on the aggregation propensity of a model protein. Journal of the American Chemical Society 2006, 128, 1683-1691.
Bostrom, M.; Tavares, F. W.; Bratko, D.; Ninham, B. W., Specific ion effects in solutions of globular proteins: Comparison between analytical models and simulation. Journal of Physical Chemistry B 2005, 109, 24489-24494.
Luzar, A.; Bratko, D., Gas solubility in hydrophobic confinement. Journal Of Physical Chemistry B 2005, 109, 22545-22552.
Cellmer, T.; Bratko, D.; Prausnitz, J. M.; Blanch, H., Protein-folding landscapes in multichain systems. Proceedings of the National Academy of Sciences of the United States of America 2005, 102, 11692-11697.
Cellmer, T.; Bratko, D.; Prausnitz, J. M.; Blanch, H., Thermodynamics of folding and association of lattice-model proteins. Journal of Chemical Physics 2005, 122, 174908/1-11.
Cellmer, T.; Bratko, D.; Prausnitz, J. M.; Blanch, H., The competition between protein folding and aggregation: Off-lattice minimalist model studies. Biotechnology and Bioengineering 2005, 89, 78-87.
Wu, J.Z.; Bratko, D.; Prausnitz, J.M., Interaction between Like-Charged Colloidal Spheres in Electrolyte Solutions, Proceedings of the National Academy of Sciences of the United States of America 1998, 95, 15169-15172.
