Optimization of an endovascular magnetic filter for maximized capture of magnetic nanoparticles.
To computationally optimize the design of an endovascular magnetic filtration device that binds iron oxide nanoparticles and to validate simulations with experimental results of prototype devices in physiologic flow testing. Three-dimensional computational models of different endovascular magnetic filter devices assessed magnetic particle capture. We simulated a series of cylindrical neodymium N52 magnets and capture of 1500 iron oxide nanoparticles infused in a simulated 14 mm-diameter vessel. Device parameters varied included: magnetization orientation (across the diameter, "D", along the length, "L", of the filter), magnet outer diameter (3, 4, 5 mm), magnet length (5, 10 mm), and spacing between magnets (1, 3 mm). Top designs were tested in vitro using89Zr-radiolabeled iron oxide nanoparticles and gamma counting both in continuous and multiple pass flow model. Computationally, "D" magnetized devices had greater capture than "L" magnetized devices. Increasing outer diameter of magnets increased particle capture as follows: "D" designs, 3 mm: 12.8-13.6 %, 4 mm: 16.6-17.6 %, 5 mm: 21.8-24.6 %; "L" designs, 3 mm: 5.6-10 %, 4 mm: 9.4-15.8 %, 5 mm: 14.8-21.2 %. In vitro, while there was significant capture by all device designs, with most capturing 87-93 % within the first two minutes, compared to control non-magnetic devices, there was no significant difference in particle capture with the parameters varied. The computational study predicts that endovascular magnetic filters demonstrate maximum particle capture with "D" magnetization. In vitro flow testing demonstrated no difference in capture with varied parameters. Clinically, "D" magnetized devices would be most practical, sized as large as possible without causing intravascular flow obstruction.
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.|Department of Bioengineering, University of California, Berkeley, CA, USA.
Sravani
S
Kondapavulur
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Andre M
AM
Cote
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Kiel D
KD
Neumann
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Caroline D
CD
Jordan
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
David
D
McCoy
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Marc C
MC
Mabray
Department of Bioengineering, University of California, Berkeley, CA, USA.
Derek
D
Liu
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Chia-Hung
CH
Sze
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Ayushi
A
Gautam
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Henry F
HF
VanBrocklin
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA.
Mark
M
Wilson
Department of Radiology and Biomedical Imaging, University of California, 505 Parnassus Avenue, L-351, San Francisco, CA, 94143-0628, USA. steven.hetts@ucsf.edu.
Steven W
SW
Hetts
D001808:Blood Vessels / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry* / Q000302:isolation & purification*; D005374:Filtration / Q000295:instrumentation*; D060526:Magnetic Fields; D053758:Nanoparticles / Q000737:chemistry*
D005290:Ferric Compounds; C000499:ferric oxide
Chemofiltration; Endovascular device; Intra-arterial chemotherapy (IAC); Magnetic nanoparticles