8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

Wed 711:10-14:00P5.111Coarse graining DNA-coated colloidsBianca M. Mladek, 1 Julia Fornleitner, 2 Francisco J. Martinez-Veracoechea, 3 andDaan Frenkel 31 Department of Structural and Computational Biology, Max F. Perutz Laboratories,Campus Vienna Biocenter 5, 1030, Vienna, Austria2 Institute of Solid State Research, Forschungszentrum Jülich, Juelich, Germany3 Department of Chemistry, University of Cambridge, Cambridge, United KingdomDNA strands which are chemically attached to the surface of colloids can work as ”sticky ends”and allow colloids to bind to each other, thereby forming networks of auto-assembled particles.Studies of such DNA-coated colloids promise to offer insights into the necessary ingredients forgaining exquisite control over colloidal self-assembly. However, experimental exploration on selfassembling ordered structures is still in its infancy, with the main hurdle being the lack of understandingof the thermodynamics and kinetics of DNA-mediated self-assembly. Detailed explorationof these structures via computer simulations on the other hand is hindered by the lack ofadequate techniques and efficient coarse-grained models. In this presentation we develop modelsof DNA-coated colloids at different levels of coarse-graining and at the experimentally relevantconditions. The different models are assessed for their validity and new simulation techniquesdeveloped to draw the phase diagram of such colloids. Finally, our findings (as e. g. meltingtemperature of the crystals or equilibrium lattice spacing) are compared to experimental results,showing agreement to within few percent and proving the strength of our coarse-grained models.111