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Physical Society Colloquium
Nadrian Siemann
Department of Chemistry Unusual motifs of DNA present an extremely favourable construction medium. The sticky-ended association of DNA molecules occurs with high specificity and diversity. It results in the formation of B-DNA, whose structure is well known. The use of stable branched DNA molecules permits one to make stick-figures and topological targets. We have used this strategy to construct covalently closed DNA polyhedra, knots, Borromean rings and a nanomechanical device. A central goal of DNA nanotechnology is the deliberate construction of periodic matter. DNA double crossover molecules (DX) with sticky ends are rigid branched species which can be designed to tile the plane, producing arrays about a micron in size. It is possible to decorate the simple DX molecule with DNA hairpins which protrude from the plane of the two dimensional array and are visible using Atomic Force Microscopes. We can change the spacing of these features by design and modify the appearance of the arrays by adding or removing these protrusions. Note: Ned Seeman was trained as a crystallographer but earns his living in a Chemistry department. The colloquium is designed to be comprehensible to all PHYSICS undergraduates, graduates, research staff and faculty. Refreshments will be served after the colloquium in the lounge. Meet the speaker and bring your favourite questions.
Friday, November 13th 1998, 15:30 |