Development of a magnetic nanoparticle susceptibility magnitude imaging array

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Medical Imaging

Background:

• Emerging diagnostic and therapeutic applications of magnetic nanoparticles (mNPs) in medicine require advanced imaging solutions.
• Existing imaging technologies may not meet the cost or performance demands for widespread clinical adoption of mNPs.

Purpose of the Study:

• To develop and validate a low-cost magnetic nanoparticle imager for emerging clinical needs.
• To assess the feasibility of using digitally controlled drive coils and compensated magnetometers for mNP imaging.

Main Methods:

• Design and mathematical modeling of a novel mNP imager utilizing multiple-frequency, continuous-wave operation.
• Prototyping and testing with active magnetic field compensation, depth sensitivity, and linearity measurements.
• Evaluation of system frequency responses for different mNP sizes and tomographic imaging performance.

Main Results:

• Achieved active magnetic field compensation of 185x, depth sensitivity up to 2.5 cm, and excellent linearity (R(2) > 0.98).
• Distinguished between 10 nm, 40 nm, and 100 nm mNPs based on system frequency responses.
• Demonstrated a contrast-to-noise ratio of 23 for mNPs at 1 cm depth and successful imaging in a biological sample (pork sausage).

Conclusions:

• The proposed mNP imaging approach offers a cost-effective solution for emerging medical applications.
• The system shows promise for extension to larger arrays with higher resolution for clinical use.
• This technology has potential for in-vivo diagnostics and therapeutics utilizing magnetic nanoparticles.