Controlled Nanoconfinement in a Microfluidic Modular Bead Array Device via Elastomeric Diaphragm Collapse for...

Area of Science:

• Biotechnology
• Nanotechnology
• Biophysics

Background:

• Diffusional transport limitations hinder biomolecular binding kinetics.
• Nanoscale confinement strategies can overcome these limitations.
• Efficient receptor screening requires enhanced binding affinity measurements.

Purpose of the Study:

• To develop a modular and multiplexed device for creating nanoconfinement.
• To enhance receptor binding kinetics for improved screening and selection.
• To validate the device's performance in accelerating biomolecular interactions.

Main Methods:

• Utilized an elastomeric diaphragm collapsing onto microbead arrays for nanoconfinement.
• Integrated a strain sensor for controlled vertical displacement and nanoposts for lateral extent control.
• Employed repeated diaphragm withdrawal to promote bulk transport and enhance binding.
• Enabled multiplexed screening in microwells and downstream quantification via quantitative PCR (q-PCR).

Main Results:

• Demonstrated significantly enhanced biomolecular binding under nanoconfinement (1 Hz pressurization).
• Achieved rapid DNA immobilization with a time constant of ~6 minutes compared to >60 minutes without confinement.
• Showcased saturating binding of target molecules with optimal aptamers, reaching 88% site occupancy versus 5% without confinement.
• Validated the screening of candidate receptors based on binding affinity parameters.

Conclusions:

• The developed nanoconfinement device effectively accelerates biomolecular binding kinetics.
• This platform facilitates efficient multiplexed screening and selection of receptors based on binding affinities.
• The technology holds promise for applications in diagnostics and drug discovery.