Anthracene-Based Tetraimidazolium Nanotube as Molecular Glue for DNA Hierarchically Chiral Assembly in Water.

In the field of DNA-based nanotechnology, the molecular recognition mechanism inherent to base pairing is harnessed to precisely regulate the structure and functionality of DNA assembly materials. In this work, we present an anthracene-based tetraimidazolium nanotube (1·4Cl-) that serves as molecular glue to mediate the hierarchically chiral assembly of oligonucleotides in water. First, 1·4Cl- facilitates the formation of hydrogen bonding between nucleobases both within and outside its hydrophobic cavity. This host-guest recognition promotes the formation of consecutive base pairs of oligonucleotides, thereby driving the transformation of oligonucleotides from single-stranded to double-stranded DNA structures. Second, these nanotube-mediated DNA assemblies are triggered to further achieve hierarchically chiral assembly through M-twisted stacking of the anthracene rings, resulting in pronounced circularly polarized luminescence. This anthracene-twisted stacking interactions between the complexed nanotubes promote interstrand entanglement, which in turn drives the self-assembly of individual DNA units into superhelical structures with diameters reaching up to ∼25 nm and lengths extending to the micrometer scale. This work demonstrates that supramolecular macrocycles can not only reconfigure DNA strand topology but also encode chiroptical properties into higher-order architectures, thereby opening new way for the design of supramolecular chiroptical materials derived from DNA-based building blocks.