wangzhe

Nature Nanotechnology, Published online: 22 December 2023; doi:10.1038/s41565-023-01556-3

Conserved regions of the circular DNA sequence of the M13mp18 bacteriophage, which is used as a scaffold for DNA origami construction, are targeted with specific hybridization-chain-reaction probes. The probes enable sensitive detection of DNA origami nanostructures in cells, organoids and tissues to assess their biodistribution and stability.

A solution-based, DNA-programmable, and highly efficient nanowelding process generates conductive threads in self-assembled nanoparticle “molecules” and “polymers”. The process starts with a gap-specific Ag₂S deposition in pre-formed gold nanostructures. It ends with Ag₂S-directed gold-atom diffusion and a reduction of the resulting AgAuS primer phase to give conductive Au/Ag alloyed junctions.

Abstract

Self-assembly of nanomaterials, directed by molecular or supramolecular interactions, is a powerful strategy to build nanoscale devices. Despite many advantages of such solution-based processes, a big challenge is to realize interparticle ohmic contacts toward facilitated charge transport over a long distance. We report a new concept of primed nanowelding to thread solution-borne nanoparticles in prescribed assemblies. The process starts with a gap-specific deposition of Ag₂E (E=S, Se) materials in pre-assembled gold structures, which spontaneously transform into AgAuE semiconductors via directional gold diffusion. Treatment with tributylphosphine generates alloyed Au/Ag welding spots that conductively wire-up nanoparticles into discrete “molecules” and micron-long “polymers”. This method is compatible with DNA programming and delivers a possible way to solve the problem of the carrier-transport dilemma in solution-processed nanostructures for better-functioning nanodevices.