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Zhuo, Rebecca

Publications and source records attributed to Zhuo, Rebecca.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Litters of self-replicating origami cross-tiles

Significance In nature, self-replication and exponential growth are common. Here we introduce a system of artificial self-replicators based on DNA origami cross-tile motifs. Unlike previous systems based on making a single copy of a parent template, the cross-tile systems, like many natural species, can produce “litters” of offspring per generation. The cross-tiles enable a ladder-like structure to crystallize from the template on cooling. UV exposure covalently binds the assembled components of the offspring and heating releases the autonomous daughters from the parent, up to 10 offspring per cycle. The enhanced growth rate speeds up experimental studies and provides an evolutionary advantage for selection.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Multivalent, multiflavored droplets by design

Nature self-assembles functional materials by programming flexible linear arrangements of molecules and then folding them to make 2D and 3D objects. To understand and emulate this process, we have made emulsion droplets with specific recognition and controlled valence. Uniquely monovalent droplets form dimers: divalent lead to polymer-like chains, trivalent allow for branching, and programmed mixtures of different valences enable a variety of designed architectures and the ability to subsequently close and open structures. Our functional building blocks are a hybrid of micrometer-scale emulsion droplets and nanoscale DNA origami technologies. Functional DNA origami rafts are first added to droplets and then herded into a patch using specifically designated “shepherding” rafts. Additional patches with the same or different specificities can be formed on the same droplet, programming multiflavored, multivalence droplets. The mobile patch can bind to a patch on another droplet containing complementary functional rafts, leading to primary structure formation. Further binding of nonneighbor droplets can produce secondary structures, a third step in hierarchical self-assembly. The use of mobile patches rather than uniform DNA coverage has the advantage of valence control at the expense of slow kinetics. Droplets with controlled flavors and valences enable a host of different material and device architectures.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗