Nanobiomagnetics

Abstract

The application of nanomagnetic materials to biological systems has produced significant advances in research, diagnosis, and treatment of numerous pathologies. This chapter summarizes the major applications of magnetic materials: magnetic targeting, drug and gene delivery, magnetic separation, the use of magnetic beads in manipulating single molecules, as contrast agents in magnetic resonance imaging, and for hyperthermia. Biocompatibility requirements for magnetic materials used in these applications are reviewed.

Magnetization and Specific Absorption Rate Studies of Ball-Milled Iron Oxide Nanoparticles for Biomedicine

“…Hyperthermia cancer treatment is possible due to the capabilities of manufactured nanoparticles. With the means of achieving subsingle-magnetic domain particle sizes through various physical and chemical methods [9][10][11][12][13][14], superparamagnetic particles in the form of ferrofluids can be attained. When subjected to a magnetic field whose direction alternates rapidly, ferrofluids can absorb electromagnetic energy, which is readily dissipated to their environment by Brownian (particle rotation) and Néel (moment reorientation) relaxation mechanisms [8].…”

“…When experiments are replicated in vivo, elevated local temperatures of 40 ∘ C to 46 ∘ C can be achieved, adequate to induce cell death or cell ablation in tumor tissue [5,15,16]. Iron oxide nanoparticles are ideal for application to hyperthermia treatment as they are biocompatible even up to 250 mg/kg of body weight of direct injection [12]. The most prevalent nanoparticle systems considered for biomedical applications are based on maghemite ( -Fe 2 O 3 ) and magnetite (Fe 3 O 4 ).…”

Effect of the Molecular Weight of Poly(ethylene glycol) on the Properties of Biocompatible Magnetic Fluids

“…Poly(ethylene glycol) is a linear polymer consisting of repeated units of CH 2 −CH 2 −O, the number of which depends on the molecular weight. Polyethylene glycol and related polymers covalently bond to surfaces or are adsorbed on magnetic nanoparticles and can prolong the circulation time in the bloodstream [1,2]. The immobilization of PEG on nanoparticles increases the amount of nanoparticle uptake into cancer cells in comparison to unmodified nanoparticles [3].…”

“…Magnetic nanoparticles must remain suspended in the fluid and cannot form aggregates due to van der Waals or magnetic interactions [1].…”

Synthesis and Evaluation of Magnetic Nanoparticles for Biomedical Applications

“…Recently, they are also used in biomedical applications such as MRI contrast agents for imaging [6], magnetic hyperthermia [7], and targeted drug delivery [8] because of their size compatibility [9] to cells, genes, and viruses. A size reduction of these materials from bulk to the nanoscale permits them to display various size related properties.…”