Relaxation of Polymer Coated ${\rm Fe}_{3}{\rm O}_{4}$ Magnetic Nanoparticles in Aqueous Solution

  title={Relaxation of Polymer Coated \$\{\rm Fe\}\_\{3\}\{\rm O\}\_\{4\}\$ Magnetic Nanoparticles in Aqueous Solution},
  author={Sahar Keshavarz and Yaolin Xu and Spencer Hrdy and Clay Lemley and Tim Mewes and Yuping Bao},
  journal={IEEE Transactions on Magnetics},
Magnetic nanoparticles have shown great capability of sensing biological molecules in solution by correlating the magnetic susceptibility with the nanoparticle surface coatings. Here, we report on a new experimental approach of measuring magnetic nanoparticle relaxation. It uses a broadband ferromagnetic resonance setup specifically designed for samples in solution, enabling measurements of nanoparticles at variable frequencies up to 40 GHz. This design enables precise determination of the g… 
19 Citations

Figures from this paper

Water-soluble iron oxide nanoparticles with high stability and selective surface functionality.
A versatile approach for preparing water-soluble iron oxide nanoparticles with great stability and selective surface functionality (-COOH, -NH(2), or -SH) was demonstrated and exhibited different stabilities in biological buffers, which were directly influenced by the surface coatings.
Measurements of the exchange stiffness of YIG films using broadband ferromagnetic resonance techniques
Measurements of the exchange stiffness D and the exchange constant A of Yttrium Iron Garnet (YIG) films are presented. YIG films with thicknesses from 0.9 to 2.6 µm were investigated with a microwave
Study of structural and ferromagnetic resonance properties of spinel lithium ferrite (LiFe5O8) single crystals
The effect of B-site cation ordering on the room temperature structural and ferromagnetic resonance (FMR) properties of single crystal spinel lithium ferrite (LiFe5O8, LFO) have been investigated. A
Single-Step Preparation of Silver-Doped Magnetic Hybrid Nanoparticles for the Catalytic Reduction of Nitroarenes
It can be revealed from the results that the morphologies and the composition of the prepared silver-doped magnetic nanoparticles can be adjusted by changing the conditions during the production, which affects the efficacy of the catalysis.
Synthesis of multiple platinum-attached iron oxide nanoparticles
Multiple, small platinum (Pt, ∼2 nm) attached iron oxide nanoparticles were successfully synthesized using two different approaches. One approach involves growing Pt nanoparticles onto iron oxide
Electromagnetic characterization of strontium ferrite powders in series 2000, SU8 polymer
In this article, electromagnetic characterization of strontium hexaferrite powders and composites with SU8 was carried out to determine their compatibility with micro and millimeter wave
Interfacial perpendicular magnetic anisotropy and damping parameter in ultra thin Co2FeAl films
B2-ordered Co2FeAl films were synthesized using an ion beam deposition tool. A high degree of chemical ordering ∼81.2% with a low damping parameter (α) less than 0.004 was obtained in a 50 nm thick


Magnetic resonance in nanoparticles: between ferro- and paramagnetism
The 'quantization' model is used which includes summation of resonance transitions over the whole energy spectrum of a nanoparticle considered as a giant exchange cluster, supplemented with some phenomenological assumptions, provides satisfactory agreement with the experimental data.
Brownian magnetic relaxation of water-based cobalt nanoparticle ferrofluids
Following the synthesis of monodispersed 20nm cobalt nanoparticles via a thermal decomposition method we have successfully transferred these hydrophobic nanoparticles into the water phase using
The fabrication of high sensitive spin‐valve sensor for magnetic bead detection
Manipulation and detection of magnetic beads on a chip open up new perspectives for analysis of magnetically labeled specimens in biological and medical applications. This work has studied to achieve
One-step synthesis of highly water-soluble magnetite colloidal nanocrystals.
The monodisperse, highly water-soluble, superparamagnetic, and biocompatible magnetite nanocrystals should find immediate important biomedical applications.
Biological sensing with magnetic nanoparticles using brownian relaxation (invited)
This work demonstrates a substrate-free biomagnetic sensing approach using the magnetic ac susceptibility of ferromagnetic particles suspended in a liquid, which requires only one binding event.
Magnetization relaxation and structure of CoFeGe alloys
The magnetic relaxation of 10 and 50 nm thin films of (CoFe)100−xGex (0 at. %≤x≤35 at. %) alloys was investigated by broadband ferromagnetic resonance (FMR) experiments. 10 nm thin films exhibit a
Advances in Giant Magnetoresistance Biosensors With Magnetic Nanoparticle Tags: Review and Outlook
The theoretical and experimental results thus far suggest that magneto-nano biochip-based GMR sensor arrays and nanotags hold great promise in biomedicine, particularly for point-of-care molecular diagnostics of cancer, infectious diseases, radiation injury, cardiac diseases, and other diseases.