A Resistance-Based Microfluidic Chip for Deterministic Single Cell Trapping Followed by Immunofluorescence Staining.

Area of Science:

• Biotechnology and Biomedical Engineering
• Single-cell analysis technologies

Background:

• Microfluidic chips are essential for single-cell analysis but often lack deterministic single-cell trapping capabilities.
• Existing methods struggle with precise cell isolation, limiting downstream applications like immunofluorescence staining.

Purpose of the Study:

• To develop a novel microfluidic chip enabling deterministic single-cell trapping.
• To implement immunofluorescence staining on trapped single cells with high efficiency and minimal cell loss.

Main Methods:

• Designed a resistance-based microfluidic chip featuring specific channel geometries (circular structure, serpentine channel) to exploit the least flow resistance principle.
• Utilized numerical simulations to optimize geometric parameters for enhanced cell trapping.
• Validated chip performance using A549 and K562 cell lines, incorporating cell immobilization techniques.

Main Results:

• Achieved high single-cell trapping efficiencies of (82.7 ± 2.4)% for A549 and (84 ± 3.3)% for K562 cells.
• Demonstrated successful real-time tracking of immobilized cells during multistep immunofluorescence staining.
• Confirmed reduced cell movement and loss due to effective cell immobilization.

Conclusions:

• The developed microfluidic chip offers a simple, high-efficiency solution for deterministic single-cell trapping.
• The chip facilitates robust immunofluorescence staining, minimizing cell loss.
• This technology holds potential as an analytical platform for studying tumor cell heterogeneity and clinical diagnostics.