Magnetic needles and superparamagnetic cells.
Superparamagnetic nanoparticles can be attached in great numbers to pathogenic cells using specific antibodies so that the magnetically-labeled cells themselves become superparamagnets. The cells can then be manipulated and drawn out of biological fluids, as in a biopsy, very selectively using a magnetic needle. We examine the origins and uncertainties in the forces exerted on magnetic nanoparticles by static magnetic fields, leading to a model for trajectories and collection times of dilute superparamagnetic cells in biological fluids. We discuss the design and application of such magnetic needles and the theory of collection times. We compare the mathematical model to measurements in a variety of media including blood. For more information on this article, see medicalphysicsweb.org.
Bryant
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Senior Scientific, LLC, 11109 Country Club Dr. NE, Albuquerque, NM 87111, USA.
Sergatskov
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DA
Lovato
Debbie
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Adolphi
Natalie L
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Larson
Richard S
RS
Flynn
Edward R
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D002469:Cell Separation / Q000379:methods*; D003198:Computer Simulation; D018189:Immunomagnetic Separation / Q000379:methods*; D008280:Magnetics; D008846:Micromanipulation / Q000379:methods*; D008954:Models, Biological; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects; D009339:Needles