| Autor: |
Rizzuto FJ; Department of Chemistry, McGill University, 801 Sherbrooke St W, Montréal, QC H3A 08B, Canada., Dore MD; Department of Chemistry, McGill University, 801 Sherbrooke St W, Montréal, QC H3A 08B, Canada., Rafique MG; Department of Chemistry, McGill University, 801 Sherbrooke St W, Montréal, QC H3A 08B, Canada., Luo X; Department of Chemistry, McGill University, 801 Sherbrooke St W, Montréal, QC H3A 08B, Canada., Sleiman HF; Department of Chemistry, McGill University, 801 Sherbrooke St W, Montréal, QC H3A 08B, Canada. |
| Abstrakt: |
The self-assembly of block copolymers is often rationalized by structure and microphase separation; pathways that diverge from this parameter space may provide new mechanisms of polymer assembly. Here, we show that the sequence and length of single-stranded DNA directly influence the self-assembly of sequence-defined DNA block copolymers. While increasing the length of DNA led to predictable changes in self-assembly, changing only the sequence of DNA produced three distinct structures: spherical micelles (spherical nucleic acids, SNAs) from flexible poly(thymine) DNA, fibers from semirigid mixed-sequence DNA, and networked superstructures from rigid poly(adenine) DNA. The secondary structure of poly(adenine) DNA strands drives a temperature-dependent polymerization and assembly mechanism: copolymers stored in an SNA reservoir form fibers after thermal activation, which then aggregate upon cooling to form interwoven networks. DNA is often used as a programming code that aids in nanostructure addressability and function. Here, we show that the inherent physical and chemical properties of single-stranded DNA sequences also make them an ideal material to direct self-assembled morphologies and select for new methods of supramolecular polymerization. |
