Pros and Cons on Magnetic Nanoparticles Use in Biomedicine and Biotechnologies Applications

Abstract

In recent years, the design and synthesis of colloidal magnetic suspensions have attracted an increased interest especially in the fields of biotechnology and biomedicine because they have many applications including targeted drug delivery, cell labeling and magnetic cell separation, hyperthermia, tissue repairing, magnetic resonance imaging (MRI) contrast enhancement, enzyme immobilization, immunoassays, protein purification, etc. IntroductionMagnetic nanoparticles (MNPs) used in biomedicine must meet several requirements. They have to be non-toxic, chemically stabile, uniform in size, well stabilized under physiological conditions, biocompatible and to present high magnetization. Magnetite (Fe 3 O 4 ) and maghemite (γ-Fe 2 O 3 ) are the most suitable iron oxide nanoparticles employed for biomedical applications because they are biocompatible, have low toxicity in the human body and show a superparamagnetic behavior.Therefore, synthesis of magnetic iron oxide nanoparticles with tailored properties has attracted considerable scientific and technological interest. Various synthesis routes were developed for producing magnetic particles, such as co-precipitation, microemulsion method, thermal decomposition of different organic precursors, spray pyrolysis, and sol-gel method.For biomedical applications, magnetic iron oxide nanoparticles must be dispersed in biocompatible media in order to obtain stable colloidal suspensions. In order to prevent the particle aggregation and to improve the biocompatibility and stability, nanoparticles are coated with various surfactants: poly(ethylene glycol),

Magnetic modification of cells

“…In general, magnetic properties of the modifiers (labels) are caused by the presence of nano-or microparticles of magnetic iron oxides, namely magnetite (Fe 3 O 4 ) or maghemite (γ-Fe 2 O 3 ) or their mixtures; in some cases also ferrite particles (Fortin et al, 2008;Liu et al, 2009a), chromium dioxide particles (Hughes et al, 2007), nickel (Choi et al, 2007) or metallic cobalt (Bromberg et al, 2010) have been employed for specific purposes. Magnetic iron oxide particles prepared by different routes (e.g., combustion synthesis versus co-precipitation ones) can exhibit various effects on the treated cells (Bojin and Paunescu, 2015); also magnetic particles' surface modification (coating, stabilization) can dramatically influence the magnetic particles' biocompatibility (Bromberg et al, 2010). The attached magnetic labels usually do not have a negative effect on the viability and phenotype alternation of modified cells.…”