Microemulsion Synthesis of Magnetic Nanoparticles for MRI Contrast Enhancement

1
Microemulsion Synthesis of Magnetic Nanoparticles
for MRI Contrast Enhancement

• Jason German
• University of California, Irvine

2
Why MRI

• MRI is a non-invasive imaging technique using
  external magnetic fields and internal magnetic
  moments.
• Rapidly becoming the favored imaging technique of
  the medical profession.
• Excellent at imaging soft tissue (lesions,
  damage, etc.)
• Real time imaging ability Organ function,
  vasculature, blood flow, chemical concentration1.

3
What MRI Looks Like
4
The Cost of MRI

• Most expensive imaging modality.
• 2 - 3 million per machine.
• Requires specialized room, maintainence (10K/
  Month), and operators.
• Hospital charges 1000-4000 per scan2

5
MRI Imaging Time

• 10-30 minutes per scan
• Need to acquire images in many small slices
• Contrast, signal to noise ratio, and accurate
  image acquisition are all improved by relatively
  longer acquisition times1

6
Magnetic Nanoparticles to the Rescue

• Inject into bloodstream or tissue.
• Must be smaller than vasculature3, 100nm
• Can increase contrast reduce scan time by
• 1) Increased magnetic signal
• 2) Tailoring specific properties
• Must be coated with biocompatible material.
• Ability to attach targeted functional groups
  highly desirable.

7
Magnetic Nanoparticle Structure

• Magnetic core magnetite (FE3O4) or Hematite
  (FE203)
• Biocompatible shell, options are a variety of
  hydrophilic polymers polyethylene glycol (PEG),
  polyethylene oxide (PEO), etc4.
• Functional group attachment would require
  additional coating.

8
Nanoparticle Synthesis

• Microemulsion tiny water droplets coated with
  surfactant immersed in oil synthesis of of
  nanoparticle occurs in droplet
• Particle size can be made as small3 as 10nm
• Control uniformity using multichannel
  microfluidics device or flow focusing
  microfluidics device5

9
Expected Results

• Biocompatible magnetic nanoparticles, with size
  less than 100nm
• Use of microfluidic device enables control over
  uniform particle size. Crucial in making them
  efficient energy absorbers and accurate image
  reconstruction.
• Cheap materials and synthesis methods a big plus.
• If successful, much room for following
  experiments with clinical trials and target
  receptor coating

10
Conclusion

• MRI is an extremely useful and increasingly
  common imaging technique
• Can be very costly increased image contrast
  increases capabilities but currently requires
  increased imaging time, increasing costs
• Magnetic nanoparticles, cheaply synthesized and
  with control over size and uniformity, could
  greatly enhance contrast internally, allowing
  reduction in imaging time and thus costs.

11
References

• The Basics of MRI. Hornack, Joseph P. 2007
  http//www.cis.rit.edu/htbooks/mri/
• http//www.acor.org/ped-onc/treatment/MRI/MRI.htm
  July 2005
• Possible exploitation of magnetic
  nanoparticle-cell interaction for biomedical
  applications. Berry, Catherine C. J. Matter
  Chem., 2005, 15, 543-547
• The preparation of magnetic nanoparticles for
  applications in biomedicine. Tartaj, Pedro et
  al. J. Phys. D Appl. Phys. 36, 2003, R182-R197
• Flow Focusing A Versatile Technology to Produce
  Size Controlled Nanoparticles. Martin-Banderas,
  Lucia et al. Small, 2005, 1, No.7, 688-692