Chemotermally fueled transient self-assembly of gold nanoparticles

Abstract

Inspired by biology, the field of supramolecular self-assembly evolved over the years from thermodynamical equilibrium structures towards dissipative assemblies, where molecular building blocks assemble out-of-equilibrium for the time being of fuel consumption. These dissipative assemblies in nature fulfill actions like transport, movement, and catalysis among others. More recently, controlling transient states of nanoparticles using chemical fuel is an emerging field for the creation of active matter, and gives the possibility to exploit new materials with unusual and adaptive properties (e.g. optical, electrical, mechanical). Examples in literature are still rare, due to difficulties of bridging different length scales with the fuel being on the molecular and building blocks on the nanoscopic scale. We report here on coupling a chemothermal cycloaddition reaction with thermosensitive DNA-coated gold nanoparticles[2] (AuDNA) (Figure 1: Coupling chemothermal reaction cycle with thermosensitive DNA coated gold nanoparticles). AuDNA undergo transient redispersion for the time of heat production by the exothermic reaction. After the excessive heat dissipates, AuDNA spontaneously cluster due to DNA rehybridization. Through adjusting the amount of fuel added, different transient states could be accessed as well as their lifetime could be controlled. To the best of our knowledge, this is the first example of coupling thermosensitive nano building blocks with a chemical reaction cycle. Our results expand the existing list of nanoscale constructs sensitive to the outcome of a chemical reaction.