Implementation of an Integrated Dielectrophoretic and Magnetophoretic Microfluidic Chip for CTC Isolation

Area of Science:

• Biomedical Engineering
• Microfluidics
• Cell Separation Technology

Background:

• Circulating tumor cells (CTCs) are crucial biomarkers for cancer diagnosis and monitoring.
• Existing methods for CTC isolation often require cell labeling, which can affect cell viability and function.
• Label-free isolation of CTCs from complex biological samples remains a significant challenge.

Purpose of the Study:

• To numerically demonstrate a novel microfluidic chip for label-free isolation of CTCs.
• To combine dielectrophoresis (DEP) and magnetophoresis (MAP) for efficient cell separation.
• To investigate the influence of microfluidic design parameters on separation performance.

Main Methods:

• Numerical simulation of a microfluidic chip integrating DEP and MAP.
• Utilizing a ferromagnet structure to generate a strong magnetic field gradient for MAP.
• Employing asymmetric orifices to create a non-uniform electric field gradient for DEP.
• Analyzing cell trajectories under combined DEP and MAP forces.

Main Results:

• The study successfully simulated the isolation of various cells, including HT-29 and MDA-231 cancer cells, from blood components (red blood cells, platelets, T cells).
• Optimized ferromagnet structure and asymmetric orifices generated strong magnetic and electric field gradients, respectively.
• The combined DEP and MAP forces enabled effective, label-free cell separation based on intrinsic properties and size.

Conclusions:

• The developed microfluidic device demonstrates high separation resolution for CTCs.
• The label-free, combined DEP and MAP approach offers a promising platform for cancer diagnostics.
• This technology has the potential for both property- and size-based cell isolation in microfluidic systems.