Hydrodynamically tunable affinities for fluidic assembly.

Area of Science:

• Materials Science
• Nanotechnology
• Fluid Dynamics

Background:

• Current micro- and nanoscale self-assembly methods predominantly use static affinities (e.g., capillary, DNA, geometric).
• These static methods struggle with dynamic reconfiguration and real-time error correction in assembled structures.
• Limitations exist in adapting static self-assembly for complex, adaptable nanoscale architectures.

Purpose of the Study:

• To demonstrate a new technique for tuning self-assembly affinities via hydrodynamic control.
• To enable dynamic reconfiguration and error correction in microscale self-assembly processes.
• To overcome limitations associated with static affinity-based self-assembly methods.

Main Methods:

• Utilized direct thermal modulation of a local viscosity field to hydrodynamically tune component affinities.
• Employed a thermorheological fluid exhibiting reversible sol-gel transition upon heating.
• Demonstrated the technique on 500-micrometer 2D silicon elements in a fluidic system.

Main Results:

• Successfully demonstrated dynamic alteration of the assembly point within a fluidic self-assembly process.
• Showcased the selective attraction and rejection of elements from a larger assembled structure.
• Validated the ability to dynamically control assembly using thermally modulated viscosity.

Conclusions:

• The developed technique offers a novel approach to dynamic microscale self-assembly.
• Thermal modulation of viscosity provides a versatile method for controlling component interactions.
• This approach holds potential for overcoming limitations in current static affinity-based self-assembly techniques.