“Easy Colloidal Crystallization: Building an Automated Machine and Seeding Nucleation”
Larry E. Luster, Jordan Nobles, Janna Lowensohn, W. Benjamin Rogers
Hampton University / Chemical Engineering
Hosted by Rogers' Lab
DNA coated particles spontaneously self-assemble into colloidal crystals over a narrow temperature range. Confirming that a crystal has formed requires the use of a microscope for the duration of the crystallization process. We present a custom-built microscope with precise temperature control and automated image acquisition optimized for DNA-coated colloidal-crystallization experiments. In this regime, complementary sequences of ssDNA provide the temperature-dependent attraction between micro-scale polystyrene colloids. Using this microscope, we begin to examine the role of “seeds” as catalysts for crystallization. Specifically, we ask if adding larger seed particles to a solution of smaller particles affects crystal size, growth rate and geometry.