Herein, we report the self-assembly and multimodal shape transformation of dual-responsive DNA di- and triblock copolymers. Dual-responsive DNA diblock copolymer was synthesized by coupling a thermoresponsive polymer, poly(N-isopropylacrylamide (PNIPAM), and an oligonucleotide. DNA-b-PNIPAM possesses thermoresponsive properties of PNIPAM as well as molecular recognition properties of DNA. Thus, they undergo reversible temperature-triggered transition at lower critical solution temperature (LCST) between molecular DNA and polymer micelles with high density DNA corona. The hybridization of DNA-b-PNIPAM and DNA-modified nanoparticles generates functional nanoparticles showing unique temperature-dependent aggregation and disaggregation behaviors due to the dual-responsive nature of DNA-b-PNIPAM. DNA triblock copolymers of DNA-b-PNIPAM-b-PMA were synthesized by introducing a hydrophobic block, poly(methyl acrylate) (PMA), to DNA/PNIPAM block copolymers, which form spherical micelles at room temperature. They are capable of nanoscale shape transformation through the combination of thermal trigger and DNA binding. DNA-b-PNIPAM-b-PMA micelles undergo sphere-to-cylinder shape changes above LCST due to the conformational change of PNIPAM. The shape change is reversible, and fast cylinder-to-sphere transition occurs when the temperature is lowered below LCST. The low temperature spherical morphology can also be accessed while keeping the temperature above LCST by introducing complementary DNA strands with single stranded overhang regions. These results demonstrate the multidimensional shape changing capability of DNA-b-PNIPAM-b-PMA enabled by the dual-responsive property.

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The emulsion‐based self‐assembly of nanoparticles into low‐dimensional superparticles of hollow vesicle‐like assemblies is reported. Evaporation of the oil phase at relatively low temperatures from nanoparticle‐containing oil‐in‐water emulsion droplets leads to the formation of stable and uniform sub‐micrometer vesicle‐like assembly structures in water. This result is in contrast with those from many previously reported emulsion‐based self‐assembly methods, which produce solid spherical assemblies. It is found that extra surfactants in both the oil and water phases play a key role in stabilizing nanoscale emulsion droplets and capturing hollow assembly structures. Systematic investigation into what controls the morphology in emulsion self‐assembly is carried out, and the approach is extended to fabricate more complex rattle‐like structures and 2D plates. These results demonstrate that the emulsion‐based assembly is not limited to typical thermodynamic spherical assembly structures and can be used to fabricate various types of interesting low‐dimensional assembly structures.

We report the rational design and fabrication of unusual low-dimensional DNA nanostructures through programmable and sequence-specific peptide interactions. Dual-bioactive block copolymers composed of DNA and amino acid-based polymers (DNA-b-poly­(amino acid)) were synthesized by coupling oligonucleotides to phenylalanine (Phe)-based polymers. Unlike prototypical DNA block copolymers, which typically form simple spherical micelles, DNA-b-poly­(amino acid) assemble into various low-dimensional structures such as nanofibers, ribbons, and sheets through controllable amino acid interactions. Moreover, DNA-b-poly­(amino acid) assemblies can undergo protease-induced fiber-to-sheet shape transformations, where the morphology change is dictated by the type of enzymes and amino acid sequences. The peptide-based self-assembly reported here provides a programmable approach to fabricate dynamic DNA assemblies with diverse and unusual low-dimensional structures.

Chemical and functional anisotropy in Janus materials offer intriguing possibilities for constructing complex nanostructures and regulating chemical and biological reactions. Here, the authors report the fabrication of Janus nanosheets from molecular building blocks composed of two information‐carrying biopolymers, DNA and peptides. Experimental and structural modeling studies reveal that DNA–peptide diblock conjugates assemble into Janus nanosheets with distinct DNA and peptide faces. The surprising level of structural control is attributed to the exclusive parallel β‐sheet formation of phenylalanine‐rich peptides. This approach is extended to triblock DNA1–peptide–DNA2 conjugates, which assemble into nanosheets presenting two different DNA on opposite faces. The Janus nanosheets with independently addressable faces are utilized to organize an enzyme pair for concerted enzymatic reactions, where enhanced catalytic activities are observed. These results demonstrate that the predictable and designable peptide interaction is a promising tool for creating Janus nanostructures with regio‐selective and sequence‐specific molecular recognition properties.