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Magnetic Nanocomposites and Their Biomedical Applications
Published in Suvardhan Kanchi, Rajasekhar Chokkareddy, Mashallah Rezakazemi, Smart Nanodevices for Point-of-Care Applications, 2022
Rajasekhar Chokkareddy, Raghavendra Vemuri, Nookaraju Muralasetti, Gan G. Redhi
Nanomaterials or nanostructured materials at least one dimension of which lies in the 1–100 nm range include nanoparticles, quantum dots, nanorods, nanowire, and nano-rings. The nanoparticles or nanomaterials are used in many applications, as shown in Figure 20.1 [11]. Thin films and bulk materials are also constructed from nanoscale building blocks or nanoscale structures [12]. Richard Feynman explored the manipulating possibility of material at an individual atomic or molecular level. Norio Taniguchi, a scientist at the University of Tokyo in 1974, first introduced nanotechnology. He referred to nanotechnology as an engineer, the materials precisely at the nanometer level. The research on nanoscience development and nanostructure investigation was started around 1980 with the invention of the scanning tunneling microscope (STM). Then the nanostructure solids concept was suggested [13,14]. The nanostructure size of the single sugar molecule is nearly 1 nm measured by Albert Einstein during the study from his doctoral degree then-experimental work diffusion data of sugar in water [15]. A non-nano-crystalline matrix of one material filled with the nanoparticles of another material is present in some nanocomposite materials. The addition of nanoparticles enhanced improvement in mechanical strength, toughness, and electrical conductivity. Magnetic nanoparticles are a set of nanoparticles that can be influenced by a magnetic field. Magnetic nanoparticles have promising applications for magnetic hyperthermia, magnetic resonance imaging (MRI), drug delivery, and magnetic resonance tomography (MRT).
Environmental Nanotechnology: An Introduction
Published in M. H. Fulekar, Bhawana Pathak, Environmental Nanotechnology, 2017
In nano sciences, nanoscale deals with the smaller parts of matter that can be manipulated at the nanoscale that the resulting materials often have different optical or electrical properties from the same material at the micro or macro scale (e.g. nano titanium oxide is a more effective catalyst than microscale titanium oxide). Magnetic nanoparticles and nano catalysts are often examples of using these materials for the treatment of polluted water for drinking, sanitation and irrigation. Nano-catalysts can chemically degrade pollutants. Zeolites can also be fabricated to separate harmful dynamic form of water to remove heavy metal ions. Naturally occurring altapulgite clays (Khider et al., 2004) and zeolite are also used in nano filtration technology. Researchers are developing new classes of nano porous materials that are more effective than conventional filters.
The Basis of Nanomagnetism: An Overview of Exchange Bias and Spring Magnets
Published in S. K. Sharma, Exchange Bias, 2017
Navadeep Shrivastava, M. Singh Sarveena, S. K. Sharma
In this section, we will discuss, within the framework of the book, the bulk and surface contributions of anisotropy to the MA. Usually, MCA and shape anisotropy make a major contribution to the MA. In thin films and multilayers, strain effects can give rise to the so-called magnetoelastic anisotropy. Contributions of interface anisotropy become important, depending on the interface properties of the different layers. Magnetic nanoparticles, drastically different from those of their bulk counterparts, are advantageous for utilization in a variety of applications such as storage media and probes in the biomedical sciences. Their fundamental magnetic properties such as blocking temperature (TB), spin life time (τ), coercivity (Hc), and susceptibility (χ) are strongly influenced by the nanoscaling laws. Hence, these scaling relationships can be used to control magnetism from ferromagnetic to superparamagnetic regimes. For example, life time of a magnetic spin is directly related to the MA energy and also to the size and volume of nanoparticles (Gaier 2009).
Kinetic resolution of racemic naproxen methyl ester by magnetic and non-magnetic cross-linked lipase aggregates
Published in Preparative Biochemistry & Biotechnology, 2020
Sema Salgın, Mustafa Çakal, Uğur Salgın
The magnetic nanoparticles were synthesized by cost effective co-precipitation in our laboratory. First, FeSO47H2O and FeCl3 salts (the mole ratio of Fe+2/Fe+3 = 1/2) were dissolved in 50 mL de-ionized water in room temperature for 1–2 min by using a sonicator (Elma S30H). 2 mL NH4OH solution was added in reaction medium and then by adding 300 µL oleic acid. The reaction stayed for 1 h reflux at 800 rpm and 80 °C under air atmosphere. The black precipitate obtained from the aging process was washed with deionized water by using a neodymium magnet until pH = 7. The magnetic iron oxide nanoparticles (MIONPs) synthesized were freeze-dried (Telstar, LyoQuest-85) and then stored at 4 °C. In order to obtain functionalized MIONPs, the surfaces of these nanoparticles were modified with APTMS by the silanization reaction. MIONPs were sonicated for 30 min at room temperature in a solution containing methanol, deionized water, and APTMS. By adding glycerol to the solution, silanization reaction carried out at 90 °C and 6 h by stirring at 800 rpm.[15]
Delivery of pemetrexed by magnetic nanoparticles: design, characterization, in vitro and in vivo assessment
Published in Preparative Biochemistry & Biotechnology, 2020
Güliz Ak, Didem Aksu, Eda Çapkın, Özge Sarı, Ilgın Kımız Geboloğlu, Şenay Hamarat Şanlıer
Magnetic nanoparticles are preferred in drug delivery systems since they effectively deliver drug molecules to the desired site by applying an external magnetic field. In addition to its use in drug delivery systems, magnetic nanoparticles are used as gene-therapy and magnetic resonance imaging contrast agents in medical applications. The application of magnetic nanoparticles in living systems requires consideration of properties such as size, surface charge, and hydrodynamic radius. The surface of magnetic nanoparticle is coated with polymer to prevent the aggregation of the magnetic nanoparticles, the interaction of the surface charge with the ligand, and to absorb the drug onto the particle.[6,14,15]
Remediation of water and wastewater by using engineered nanomaterials: A review
Published in Journal of Environmental Science and Health, Part A, 2018
Obadia K. Bishoge, Lingling Zhang, Shaldon L. Suntu, Hui Jin, Abraham A. Zewde, Zhongwei Qi
Zhang et al.[42] found that magnetic nanomaterials of ferrosoferric oxide (Fe3O4) can remove oil from wastewater when coated with silica and 3-amino-propyltriethoxysilane under the influence of quartenized chitosan grafted to yield quarternized chitosan-coated magnetic nanomaterials. Magnetic nanoparticles are ideal because they possess fast kinetics, high removal capacity, and great reactivity for pollutant removal owing to their small particle size, high surface area, and magnetic property.[73–78] All these characteristics enhance the performance of these nanomaterials in removing contaminants.