Journal ArticleDOI
Optimization of Long-Term Stability of Magnetic Fluids from Magnetite and Synthetic Polyelectrolytes
George David Mendenhall,Yunpeng Geng,James Hwang +2 more
- Vol. 184, Iss: 2, pp 519-526
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TLDR
The long-term stability of the ferrofluids made with PMAA was optimal at pH 7 (close to the measured isoelectric point of the magnetite, 5.9) and improved at all pH values with increasing surfactant concentration.Abstract:
Nanometer-sized suspensions of magnetite (Fe3O4) stabilized with polymeric surfactants, principally poly(methacrylic acid) (PMAA), were prepared by precipitation or sonication and studied by a variety of techniques. The long-term stability of the ferrofluids made with PMAA was optimal at pH 7 (close to the measured isoelectric point of the magnetite, 5.9) and improved at all pH values with increasing surfactant concentration. With extended times of sonication the molecular weight and polydispersity of the PMAA decreased, although magnetite in the ferrofluid was not oxidized (X-ray). Particle diameters of 9-38 nm were measured by saturation magnetization, electron microscopy, and dynamic light scattering. Centrifugation at 8,000 rpm removed the magnetite from the suspensions together with roughly one molecule of PMAA for each magnetite particle in the fluid, with the average number increasing with higher concentrations and average molecular weights of the polymer.read more
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Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications
Ajay Kumar Gupta,Mona Gupta +1 more
TL;DR: This review discusses the synthetic chemistry, fluid stabilization and surface modification of superparamagnetic iron oxide nanoparticles, as well as their use for above biomedical applications.
Journal ArticleDOI
Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications
Sophie Laurent,Delphine Forge,Marc Port,Alain Roch,Caroline Robic,Luce Vander Elst,Robert N. Muller +6 more
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Magnetofection: enhancing and targeting gene delivery by magnetic force in vitro and in vivo.
Franz Scherer,Martina Anton,Ulrike Schillinger,Julia Henke,C Bergemann,Achim Krüger,Bernd Gansbacher,Christian Plank +7 more
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Journal ArticleDOI
Magnetite Nanoparticle Dispersions Stabilized with Triblock Copolymers
L. A. Harris,Jonathan D. Goff,A. Y. Carmichael,J. S. Riffle,J. Jonathan Harburn,and T. G. St. Pierre,Martin Saunders +6 more
TL;DR: In this paper, the authors developed complexes of magnetite nanoparticles coated with well-defined hydrophilic polymers so that they could be dispersed in aqueous fluids, and the results showed that these polymers can bind irreversibly to magnetite at the physiological pH.
Journal ArticleDOI
Preparation and Properties of Magnetite and Polymer Magnetite Nanoparticles
TL;DR: In this article, the magnetite core and polymeric shell were synthesized in a single inverse microemulsion and the particle size was varied in the range 80−320 nm by changing of the monomer concentration and water/surfactant ratio.
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