Digital cell counting device integrated with a single-cell array

Area of Science:

• Biomedical Engineering
• Microfluidics
• Sensor Technology

Background:

• Accurate cell counting is crucial for biological research and diagnostics.
• Existing methods can be time-consuming, labor-intensive, or require specialized equipment.
• There is a need for rapid, miniaturized, and cost-effective cell counting solutions.

Purpose of the Study:

• To develop and validate a novel, integrated cell counting device.
• To demonstrate a cell counting method based on shadow imaging using a single-cell array.
• To enable high-throughput and sensitive cell enumeration.

Main Methods:

• Fabrication of a single-cell array with microcavities on a complementary metal oxide semiconductor (CMOS) sensor.
• Cell trapping using negative pressure to establish a one-on-one relationship between cells and microcavities.
• Shadow imaging technique utilizing light diffraction patterns for cell detection and enumeration.
• Integration of cell entrapment, image acquisition, and digital cell counting within a single device.

Main Results:

• Demonstrated accurate cell counting with a linear correlation to microscopic observation (r² = 0.99).
• Achieved rapid image acquisition over a wide field-of-view (30 mm²) in 1/60 seconds.
• Validated the system's capability for detecting extremely low cell concentrations (25–15,000 cells/mL).

Conclusions:

• The proposed shadow imaging method on a CMOS sensor provides a simple, rapid, and miniaturized solution for cell counting.
• This platform is suitable for routine laboratory use and applications requiring detection of low cell densities.
• The integrated device offers potential for point-of-care diagnostics and high-throughput screening.