Nanostructured magnetic materials possess a range of unique and powerful properties; they interact with an external magnetic field to produce actuation, temperature increase, and alteration in the magnetic field (e.g. for the purposes of creating contrast in Magnetic Resonance Imaging applications). As a result, nanostructured magnetic materials are used across a wide range of biomedical and industrial applications.
In biomedical applications the surface of the particles is most commonly functionalized with targeting species such as antibodies, aptamers, peptides etc., giving the particles the ability to self-assemble at a malignant site. This enables magnetic particles to act as MRI contrast agents with a much greater degree of targeting efficiency than previous generation gadolinium-based contrast agents.
The particles can also act as therapeutic agents. Magnetic materials can be directed to a tumor or other site, and heated using an alternating external magnetic field. This results in either an increase in therapeutic efficacy of active pharmaceutical ingredients already present in the system, or in the case of more aggressive heating, necrosis of the cells in the immediately surrounding area and thereby tumor reduction.
In industrial applications such as catalysis, magnetic particles are often embedded in catalytic supports to enable efficient loading and separation of the catalyst pre and post reaction cycles.
Magnetic materials can be used to generate heat in the catalytic reaction. In this application catalytic materials (e.g. palladium nanoparticles) decorate the surface of a larger magnetic particle. An alternating external magnetic field results in significant temperature increase on the catalytic surface. This enables high temperature reactions to be undertaken in low boiling point solvents such as water and a more efficient energy transfer into chemical reactions.
Magnetic properties of nanostructured materials – such as magnetic state, remnant magnetization and magnetic anisotropy – are directly related to the size, shape and architecture of the underlying particles as well as the relationship between the particle dimensions and magnetic domain size of the material. Fabrication of magnetic materials with the desired properties (e.g. hard or soft magnets) therefore requires precision control over the underlying nanoparticles.
Typically, nanoparticle suppliers provide non-uniform or polydisperse (CV values >20% or even >50%) material in which particles have a range of sizes, shapes and architectures. This results in substantially diminished performance as particles in such material have a range of magnetic properties.
Particle Works offers a unique high-performance magnetic material: Cobalt- Iron Oxide Core-Shell nanoparticles. The material brings the following benefits:
|Oxidatively stable magnetic nanoparticles||We recommend powdered Co-Fe3O4 for re-dispersion and processing in organic solvents|
|We recommend PEG functionalized Co-Fe3O4 for re-dispersion and processing in aqueous solvents. (available on request only)|