Instead, the DNA «glue» prevented the separation by providing an attractive force between the flat facets of the blocks and the tethers on the spheres, as well as a repulsive force between the non-pairing tethers on same - shaped objects.
«We explored an alternate idea: the introduction of shaped nanoscale «blocks» decorated with DNA tetherson each facet to control the directional binding of spheres with complementary DNA tethers,» Gang said.