High-gradient microstructured hybrid microfluidic chip for rare tumor cell capture.

Area of Science:

• Biomedical Engineering
• Oncology
• Microfluidics

Background:

• Circulating tumor cells (CTCs) are crucial biomarkers for cancer diagnosis and monitoring.
• Early cancer detection significantly improves patient outcomes.
• Microfluidic chips offer an effective physical method for CTC capture based on cell properties.

Purpose of the Study:

• To investigate and compare the performance of three high-gradient microstructured hybrid microfluidic chips (HGMH-Chips) with different geometric gradient designs (linear, sawtooth, waveform).
• To evaluate the capture efficiency, purity, and cell viability of these chips for isolating circulating tumor cells (CTCs) from complex biological samples.

Main Methods:

• Design and fabrication of three HGMH-Chips with linear, sawtooth, and waveform gradient structures.
• Multiphysics simulations to analyze pressure distribution within the chips.
• Experimental evaluation using cancer cell lines (MDA-MB-231, A549) and mixed samples with leukocytes.
• Assessment of capture efficiency, purity, and cell viability.

Main Results:

• The sawtooth chip design demonstrated a more uniform pressure drop compared to linear and waveform designs.
• The sawtooth chip achieved a capture efficiency of up to 70% for cancer cells.
• High-gradient designs achieved up to 98% purity in isolating cancer cells from samples containing leukocytes.
• The microarray structure enhanced the stabilization and separation of captured cells.

Conclusions:

• The novel sawtooth HGMH-Chip design significantly improves CTC capture efficiency and purity.
• This microfluidic approach shows great promise for the effective isolation of CTCs from complex biological samples.
• The developed chip design is a valuable tool for advancing cancer diagnostics and monitoring.