Trapping cells in paper for white blood cell count

Area of Science:

• Biomedical Engineering
• Point-of-Care Diagnostics
• Nanotechnology

Background:

• White blood cell (WBC) count is a critical health indicator, with abnormal levels linked to infections, cancer, inflammation, cardiovascular diseases, and Type 2 diabetes.
• Current WBC counting methods rely on centralized laboratories, requiring specialized equipment and personnel, limiting accessibility in low-resource settings.
• There is a need for rapid, cost-effective, and accessible methods for WBC quantification, especially for point-of-care applications.

Purpose of the Study:

• To develop and demonstrate a novel vertical flow platform for rapid white blood cell quantification.
• To enable accurate WBC counting in low-resource settings using a simple, instrument-free method.
• To assess the platform's potential for point-of-care diagnostic applications.

Main Methods:

• A vertical flow platform utilizing a paper matrix was developed to trap white blood cells.
• White blood cells were labeled with gold nanoparticles for detection.
• Quantification was achieved by measuring the colorimetric intensity of gold nanoparticles on trapped WBCs.
• The platform requires only 15 μL of blood for analysis.

Main Results:

• The platform successfully quantified white blood cells by measuring colorimetric intensity.
• Abnormal WBC counts could be visually differentiated from normal counts.
• The method demonstrated rapid results suitable for low-resource environments.
• The platform operates without requiring external instruments, making it cost-effective.

Conclusions:

• The proposed vertical flow platform offers a rapid, low-cost, and instrument-free solution for white blood cell counting.
• This technology has significant potential for point-of-care diagnostics, particularly in resource-limited settings.
• Regular monitoring of WBC count using this accessible platform can aid in early disease detection and preventive healthcare.