Molecularly Engineered Intrinsically Healable and Stretchable Conducting Polymers

Advances in stretchable electronics concern engineering of materials with strain-accommodating architectures and fabrication of nanocomposites by embedding a conductive component into an elastomer. The development of organic conductors that can intrinsically stretch and repair themselves after mechanical damage is only in the early stages yet opens unprecedented opportunities for stretchable electronics. Such functional materials would allow extended lifetimes of electronics as well as simpler processing methods for fabricating stretchable electronics. Herein, we present a unique molecular approach to intrinsically stretchable and healable conjugated polymers. The simple yet versatile synthetic procedure enables one to fine-tune the electrical and mechanical properties without disrupting the electronic properties of the conjugated polymer. The designed material is comprised of a hydrogen-bonding graft copolymer with a conjugated backbone. The morphological changes, which are affected by the composition of functional side chains, and the solvent quality of the casting solution play a crucial role in the synthesis of highly stretchable and room-temperature healable conductive electronic materials

Assembly of Protein Stacks With in Situ Synthesized Nanoparticle Cargo

The ability of proteins to form hierarchical structures through self-assembly provides an opportunity to synthesize and organize nanoparticles. Ordered nanoparticle assemblies are a subject of widespread interest due to the potential to harness their emergent functions. In this work, the toroidal-shaped form of the protein peroxiredoxin, which has a pore size of 7 nm, was used to organize iron oxyhydroxide nanoparticles. Iron in the form of Fe²⁺ was sequestered into the central cavity of the toroid ring using metal-binding sites engineered there and then hydrolyzed to form iron oxyhydroxide particles bound into the protein pore. By precise manipulation of the pH, the mineralized toroids were organized into stacks confining one-dimensional nanoparticle assemblies. We report the formation and the procedures leading to the formation of such nanostructures and their characterization by chromatography and microscopy. Electrostatic force microscopy clearly revealed the formation of iron-containing nanorods as a result of the self-assembly of the iron-loaded protein. This research bodes well for the use of peroxiredoxin as a template with which to form nanowires and structures for electronic and magnetic applications