Hierarchical self-assembly in an RNA-based coordination polymer hydrogel.

An RNA-based coordination polymer is formed by the aqueous reaction of Cu ^I ions with the thionucleoside enantiomer (-)6-thioguanosine, (6tGH). The resulting polymer, [Cu ^I (μ ³ -S-thioG)] _n 1, has a one-dimensional structure based on a [Cu ₄ -S ₄ ] core and undergoes extensive hierarchical self-assembly transforming from oligomeric chains → rod → cable → bundle through which a fibrous gel forms, that undergoes syneresis to form a self-supporting mass. The assembly involves the formation of helical cables/bundles and, in combination with the intrinsic photoemission of the polymer, results in the material exhibiting circularly polarised luminescence (CPL).