Multiplexed Affinity-Based Separation of Proteins and Cells Using Inertial Microfluidics.

Area of Science:

• Biotechnology
• Microfluidics
• Bioseparations

Background:

• Affinity-based separation methods are crucial for isolating low-abundance proteins and rare cells from biological samples like blood.
• Existing 'bind-elute' methods are inefficient for multiplexed isolation of multiple targets.
• There is a need for rapid, high-throughput, and cost-effective techniques for simultaneous isolation of diverse biomolecules and cells.

Purpose of the Study:

• To develop a novel, inexpensive, and multiplexed affinity-based isolation method for both proteins and cells.
• To demonstrate the capability of this method for simultaneous isolation of multiple targets from complex biological mixtures.
• To apply the technique for isolating low-abundance antibodies and rare cells relevant to HIV diagnostics.

Main Methods:

• A size-coded mixture of affinity-capture microbeads was used, where different targets bind to beads of specific sizes.
• An inertial microfluidic particle sorter with a spiral channel was employed for continuous-flow sorting based on bead size.
• The method integrates binding and sorting into a single, rapid workflow for high-throughput separation.

Main Results:

• Simultaneous isolation of multiple antibodies from serum was achieved.
• Multiple cell types were successfully isolated from peripheral blood mononuclear cells and whole blood.
• Low-abundance antibodies specific to HIV antigens and rare HIV-specific cells were isolated from patient blood samples.

Conclusions:

• The developed technique offers a rapid, multiplexed, and inexpensive solution for affinity-based isolation of proteins and cells.
• This method significantly improves upon traditional binary separation techniques for complex biological samples.
• The successful isolation of HIV-specific targets demonstrates its potential for diagnostic and research applications in infectious diseases.