An aptamer-based magnetic flow cytometer using matched filtering.

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Medical Diagnostics

Background:

• Noncommunicable diseases (NCDs) management requires advanced point-of-care (PoC) testing due to global population-ageing.
• Magnetic flow cytometry offers a promising avenue for rapid cellular detection in PoC settings, particularly for cancer diagnostics.

Purpose of the Study:

• To develop and validate a giant magnetoresistive spin-valve (GMR SV) biosensor array for enhanced accuracy and throughput in cellular detection.
• To enable multi-parametric measurements comparable to optical flow cytometry (FCM) for PoC applications.

Main Methods:

• Utilized a GMR SV biosensor array with multi-stripe sensor geometry and matched filtering for improved signal-to-noise ratio (SNR).
• Employed magnetic nanoparticles (MNPs) for cell labeling and a biomimetic model using polymer microspheres for system calibration.
• Evaluated detection efficiency and counting accuracy against optical observation and for aptamer-based pancreatic cancer cell detection.

Main Results:

• Achieved enumeration and multi-parametric measurements across a wide throughput range (37-2730 cells/min).
• Demonstrated high detection efficiency (92%) and counting accuracy (95% for biomimetic models, 98% for cancer cells) with low SNR detection (2.5 dB).
• The matched filtering processing gain significantly improved detection capabilities.

Conclusions:

• The developed GMR SV biosensor array provides reliable flow cytometry capabilities for PoC diagnostics.
• This technology can significantly benefit noncommunicable disease control plans by enabling faster and more accurate diagnoses.
• The system's performance highlights its potential for widespread adoption in clinical settings.