Boosted Productivity in Single‐Tile‐Based DNA Polyhedra Assembly by Simple Cation Replacement

Abstract

Cations such as divalent magnesium ion (Mg 2 + ) play an essential role in DNA self-assembly. However, the strong electrostatic shielding effect of Mg 2 + would be disadvantageous in some situations that require relatively weak interactions to allow a highly reversible error-correcting mechanism in the process of assembly. Herein, by substituting the conventional divalent Mg 2 + with monovalent sodium ion (Na + ), we have achieved one-pot high-yield assembly of tile-based DNA polyhedra at micromolar concentration of tiles, at least 10 times higher than the DNA concentrations reported previously. This strategy takes advantage of coexisting counterions and is expected to surmount the major obstacle to potential applications of such DNA nanostructures: large-scale production.

Self‐Assembly of DNA Nanostructures in Different Cations

“…In this study, we have presented new results on DNA nanostructure self‐assembly in the presence of different monovalent and divalent cations. Our study complements existing studies on magnesium‐free assembly of DNA nanostructures (that only use Na + ) [ 31,43 ] and provides assembly conditions in a wider variety of cations. For the smaller DX motif, the structure has previously been assembled in 125 m m Ca 2+ to template morphology changes in calcium carbonate, [ 55 ] while here we show that the structure can be assembled in 10 m m Ca 2+ .…”

“…A recent study that was published during our work showed that similar DNA tetrahedra can be assembled at higher Na + (100–600 m m ) and K + (400 m m ) concentrations. [ 43 ] To our knowledge, our study is the first to show assembly of a variety of DNA nanostructures in Ba 2+ , with assembly yields comparable to a Mg 2+ ‐containing buffer for the DX and the three‐point‐star motif as well as for the larger DNA origami triangle. While our work shows that a variety of DNA nanostructures can be assembled in different cations, the choice of cation would be dependent on the specific design of the structure and the application.…”

“…While we did not observe tetrahedra formation at 10 m m Na + , K + , and Li + , another recent work showed that similar DNA tetrahedra can be assembled in buffer containing 100–600 m m Na + or 400 m m K + ions. [ 43 ]…”