DNA Nanostructures that Self-Heal in Serum

Abstract

Self-assembled DNA nanostructures have potential applications in therapeutics, diagnostics, and synthetic biology. A challenge in using DNA nanostructures in biological environments or cell culture, however, is that they may be degraded by enzymes found in these environments, such as nucleases. Such degradation can be slowed by introducing alternative substrates for nucleases, or by coating nanostructures with membranes or peptides. Here we demonstrate a means by which degradation can be reversed in situ through the repair of nanostructure defects. To demonstrate this effect, we show that degradation rates of DNA nanotubes, micron-scale self-assembled structures, are at least 4-fold lower in the presence of tiles that can repair nanotube defects during the degradation process. Micrographs of nanotubes show that tiles from solution incorporate into nanotubes and that this incorporation increases nanotube lifetime to several days in serum. We use experimental data to formulate a simple model of nanostructure self-healing. This model suggests how introducing even a relatively low rate of repair could allow a nanostructure to survive almost indefinitely because of a dynamic equilibrium between microscale repair and degradation processes. The ability to repair nanostructures could thus allow particular structures or devices to operate for long periods of time and might offer a single means to resist different types of chemical degradation.

Feedback regulation of crystal growth by buffering monomer concentration

“…We introduce a general means to implement similar control using chemistry in a closed system. Though mechanistically simple, the powerful feedback regulation imparted by monomer buffering should facilitate growth of complex hierarchical structures where growth sites are activated or deactivated during the crystallization process 38,59 or allow crystals to heal itself after damage by maintaining a constant growth potential 60 . This may be why processes such as actin and microtubule growth are so tightly regulated by coupled production and degradation reactions that also resist concentration changes.…”

Seeding, Plating and Electrical Characterization of Gold Nanowires Formed on Self-Assembled DNA Nanotubes

“…DNA nanotube structures were designed and assembled as described by Li and Schulman [ 39 ]; Scheme S1 shows the tile sequences. In summary, during self-assembly, nanotube tiles hybridized together to make a lattice, which then generated the hollow DNA nanotubes.…”

Challenges and Perspectives of DNA Nanostructures in Biomedicine

“…[117].Bottom left panel reproduced with permission from ref. [119].C opyright 2019 American Chemical Society.Bottom right panel reproduced with permission from ref. [120].C opyright 2017 American Chemical Society.b )Left panel reproduced with permission from ref.…”