Microfluidic-assisted self-assembly of information-bearing oligomers

Area of Science:

• Supramolecular chemistry
• Nanotechnology
• Materials science

Background:

• Complex self-assembled nanostructures require precise control over molecular design and reaction conditions.
• Conventional batch methods often lead to kinetic trapping, limiting yields of intricate assemblies.

Purpose of the Study:

• To achieve dynamic covalent assembly of complex imine-based nanostructures using microfluidics.
• To overcome limitations of batch processing in supramolecular self-assembly.

Main Methods:

• Utilized droplet microfluidics to generate organic solution droplets containing precursor strands and a Lewis acidic reagent (scandium triflate) in an aqueous phase.
• Employed hydrodynamic microtraps for droplet immobilization and continuous reagent extraction via interfacial diffusion.
• Controlled self-assembly by altering reagent concentration to influence imine bond formation and rearrangement.

Main Results:

• Successfully assembled imine-based molecular ladders and branched nanostructures.
• Demonstrated an error correction mechanism via Sc³⁺-catalyzed imine bond rearrangement, ensuring ladder construct registry.
• Achieved the assembly of three complementary oligo(peptoid) strands into three-way nanostructures.

Conclusions:

• Droplet microfluidics provides superior microenvironmental control for complex supramolecular self-assembly.
• Dynamic covalent chemistry within microfluidic droplets enables efficient synthesis of intricate nanostructures.
• The system allows for tunable assembly and error correction, advancing the construction of sophisticated molecular architectures.