A high-sensitivity and clogging-free microfluidic impedance flow cytometer based on three-dimensional hydrodynamic...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Cell Biology

Background:

• Microfluidic impedance flow cytometry is crucial for single-cell analysis but faces challenges with sensitivity and channel clogging.
• Existing methods often present a trade-off between high sensitivity and clog-free operation, limiting their practical application.

Purpose of the Study:

• To develop a microfluidic impedance flow cytometer that overcomes the sensitivity-clogging tradeoff.
• To achieve high impedance sensitivity for single cells without channel blockage using 3D hydrodynamic focusing.
• To validate the system's performance in cell-type classification.

Main Methods:

• A microfluidic impedance flow cytometer utilizing three-dimensional (3D) hydrodynamic focusing was designed and implemented.
• Crossflow of conductive sample fluids and insulating sheath fluids was employed to centralize electric field lines.
• Impedance amplitude dips generated by single microparticles and cells were measured and analyzed.

Main Results:

• The system demonstrated high impedance sensitivity for single cells without channel blockage.
• Quantified impedance profiles for leukemia cell lines (K562, Jurkat, HL-60) and leukocytes (neutrophil, eosinophil, monocyte, lymphocyte) were obtained.
• Recurrent neural networks achieved high classification accuracies: 93.9% for leukemia cell lines and 87.8% for leukocyte types.

Conclusions:

• The developed microfluidic impedance flow cytometer offers a promising solution for high-sensitivity, clog-free single-cell analysis.
• This technology has the potential to overcome limitations of conventional impedance flow cytometry.
• The system shows significant potential for advancing the commercial development of microfluidic cell analysis tools.