Biomedical applications based on magnetic nanoparticles

Pharmaceutical Research, 2012

Magnetite nanoparticles covalently coated with polysaccharide arabic acid are investigated as possible constituents of aqueous ferrofluids for biomedical applications. The nanoparticles have been characterized by transmission electron microscopy and with magnetic measurements. 1 H nuclear magnetic resonance T 1 relaxation experiments of the coating which cover the nanoparticles have been also carried out in an attempt to probe the dynamic (superparamagnetic) behaviour of the magnetic nanoparticles. Finally, magnetic hyperthermia experiments of the synthesized ferrofluid have been performed and the dependence of the measured Specific Absorption Rate coefficient (SAR) as a function of the amplitude of the irradiation field is discussed.

Pharmaceutical Communications

In nanotechnology field, iron oxide magnetic nanoparticles (IONPs) have gained much interest. The magnetic nanoparticles have been widely explored for applications due to ease of manufacturing and functionalization with polymers and other materials which makes them highly sensitive for many biological and biomedical applications. They transform electromagnetic energy into heat when exposed to magnetic field, and, hence, prove themselves as potent anti-cancer agent. The most advanced application of nanoscale materials towards human health is application as contrast agents in imaging modalities. MNPs proved safer as imaging contrast agents than conventional methods. MNPs have also been used in overcoming bacterial resistance and as anti-viral agent. They provide further evidences as emerging means in treatment and diagnosis of CVD and chronic inflammatory diseases like Rheumatoid arthritis. They also have employed in gene therapy to treat chronic diseases now a day.

2021

The study of magnetic nanoparticles (MNPs) is an emergent field of science in this era due to their widespread utilization in the various fields of biomedical science. Developing concerns of magnetic nanoparticles in the researcher’s field led to design a huge number of MNPs including individual or binary metallic particles, oxides, (ferrites), biopolymer coated composites, metallic carbides and graphene mediated nanoparticles. Numerous synthetic routes are defined in literature to attain the desired size, crystal structure, morphology and magnetic properties. To build up biocompatibility, MNPs subjected to surface treatments by coating with some suitable organic or inorganic biomaterials which not only improves its physical characteristics but also elevate its chemical stability. These biomaterials coat either isolatly or in a combined state to enhance the colloidal stability, magnetic properties as well as prevent it cytotoxicity and surface corrosion in the biological media. Thes...

2018

Nanoparticles have a potential impact on numerous biomedical applications. Various synthesis roots and a wide range of applications in the area of bioimaging, drug delivery biosensing, nanomedicine and Magnetic Fluid Hyperthermia (MFH) makes magnetic nanoparticles as an attractive material for bioresearch. Magnetic nanoparticles are a group of nanoparticles that can be influenced using a magnetic field. In recent time these group of particles has been the focus of more research since they have remarkable properties. In nanoscale phenomena of finite size and surface, effects start to dominate the magnetic behaviour of individual nanoparticles. Because of the widespread applications of magnetic nanoparticles [MNPs], in this context, we discuss methods of magnetic nanoparticle synthesis in the first part followed by the role of magnetic nanoparticles in different biomedical applications.

International journal of molecular sciences, 2013

Due to finite size effects, such as the high surface-to-volume ratio and different crystal structures, magnetic nanoparticles are found to exhibit interesting and considerably different magnetic properties than those found in their corresponding bulk materials. These nanoparticles can be synthesized in several ways (e.g., chemical and physical) with controllable sizes enabling their comparison to biological organisms from cells (10-100 μm), viruses, genes, down to proteins (3-50 nm). The optimization of the nanoparticles' size, size distribution, agglomeration, coating, and shapes along with their unique magnetic properties prompted the application of nanoparticles of this type in diverse fields. Biomedicine is one of these fields where intensive research is currently being conducted. In this review, we will discuss the magnetic properties of nanoparticles which are directly related to their applications in biomedicine. We will focus mainly on surface effects and ferrite nanopar...

2013

Magnetic nanoparticles present unique properties that make them suitable for applications in biomedical field such as magnetic resonance imaging (MRI), hyperthermia and drug delivery systems. Magnetic hyperthermia involves heating the cancer cells by using magnetic particles exposed to an alternating magnetic field. The cell temperature increases due to the thermal propagation of the heat induced by the nanoparticles into the affected region. In order to increase the effectiveness of the treatment hyperthermia can be combined with drug delivery techniques. As a spectroscopic technique MRI is used in medicine for the imaging of tissues especially the soft ones and diagnosing malignant or benign tumors. For this purpose ZnxCo1-xFe2O4 ferrite nanoparticles with x between 0 and 1 have been prepared by co-precipitation method. The cristallite size was determined by X-ray diffraction, while the transmission electron microscopy illustrates the spherical shape of the nanoparticles. Magnetic characterizations of the nanoparticles were carried out at room temperature by using a vibrating sample magnetometer. The specific absorption rate (SAR) was measured by calorimetric method at different frequencies and it has been observed that this value depends on the chemical formula, the applied magnetic fields and the frequency. The study consists of evaluating the images, obtained from an MRI facility, when the nanoparticles are dispersed in agar phantoms compared with the enhanced ones when Omniscan was used as contrast agent. Layer-by-layer technique was used to achieve the necessary requirement of biocompatibility. The surface of the magnetic nanoparticles was modified by coating it with oppositely charged polyelectrolites, making it possible for the binding of a specific drug.

CRC Press eBooks, 2016

Nanotechnology is revolutionizing human's life. Synthesis and application of magnetic nanoparticles is a fast burgeoning field which has potential to bring significant advance in many fields, for example diagnosis and treatment in biomedical area. Novel nanoparticles to function efficiently and intelligently are in desire to improve the current technology. We used a magnetron-sputtering-based nanocluster deposition technique to synthesize magnetic nanoparticles in gas phase, and specifically engineered nanoparticles for different applications. Alternating magnetic field heating is emerging as a technique to assist cancer treatment or drug delivery. We proposed high-magnetic-moment Fe 3 Si particles with relatively large magnetic anisotropy energy should in principle provide superior performance. Such nanoparticles were experimentally synthesized and characterized. Their promising magnetic properties can contribute to heating performance under suitable alternating magnetic field conditions. When thermal energy is used for medical treatment, it is ideal to work in a designed temperature range. Biocompatible and "smart" magnetic nanoparticles with temperature self-regulation were designed from both materials science and biomedicine aspects. We chose Fe-Si material system to demonstrate the concept. Temperature dependent physical property was adjusted by tuning of exchange coupling between Fe atoms through incorporation of various amount of Si. The magnetic moment can still be kept in a promising range. The two elements are both biocompatible, which is favored by in-vivo

ChemInform, 2012

In this review an overview about biological applications of magnetic colloidal nanoparticles will be given, which comprises their synthesis, characterization, and in vitro and in vivo applications. The potential future role of magnetic nanoparticles compared to other functional nanoparticles will be discussed by highlighting the possibility of integration with other nanostructures and with existing biotechnology as well as by pointing out the specific properties of magnetic colloids. Current limitations in the fabrication process and issues related with the outcome of the particles in the body will be also pointed out in order to address the remaining challenges for an extended application of magnetic nanoparticles in medicine.

Current Medicinal Chemistry, 2010

During this past decade, science and engineering have seen a rapid increase in interest for nanoscale materials with dimensions less than 100 nm, which lie in the intermediate state between atoms and bulk (solid) materials. Their attributes are significantly altered relative to the corresponding bulk materials as they exhibit size dependent behavior such as quantum size effects (depending on bulk Bohr radius), optical absorption and emission, coulomb staircase behavior (electrical transport), superparamagnetism and various unique properties. They are active components of ferrofluids, recording tape, flexible disk recording media along with potential future applications in spintronics: a new paradigm of electronics utilizing intrinsic charge and spin of electrons for ultra-high-density data storage and quantum computing. They are used in a gamut of biomedical applications: bioseparation of biological entities, therapeutic drugs and gene delivery, radiofrequency-induced destruction of cells and tumors (hyperthermia), and contrast-enhancement agents for magnetic resonance imaging (MRI). The magnetic nanoparticles have optimizable, controllable sizes enabling their comparison to cells (10-100 m), viruses (20-250 nm), proteins (3-50 nm), and genes (10-100 nm). Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) provide necessary characterization methods that enable accurate structural and functional analysis of interaction of the biofunctional particles with the target bioentities. The goal of the present discussion is to provide a broad review of magnetic nanoparticle research with a special focus on the synthesis, functionalization and medical applications of these particles, which have been carried out during the past decade, and to examine several prospective directions.

2009

The thesis focuses on the specific design of multifunctional magnetic nano-carriers for different biomedical areas. Different shapes of core/shell bi-magnetic nanoparticle have been synthesized by seedmediated growth, and their structural and magnetic properties have been studied. The experimental results showed that core/shell nanoparticles have a higher specific absorption rate compared to the core ones. For drug delivery application, the surface of the magnetic nanoparticles is functionalized using different techniques (Diels-Alder reaction and layer-by-layer technique). More precisely, a novel bi-functional thermo-responsive system, which consists of core/shell bi-magnetic nanoparticles with furan surface functionality, is bonded with N-(2-Carboxyethyl)maleimide through Diels-Alder reaction. The chemotherapeutics doxorubicin is attached onto the surface of the nanocarriers, and a high loading efficiency of 92% is obtained. This system with high responsiveness to a high frequency external alternating magnetic field shows a very good therapeutic efficiency in hyperthermia and drug release at relatively low temperatures (50 °C). On the other hand, a switch-controlled drug release is realized by coating the core/shell bi-magnetic nanoparticle with a pH-and thermo-responsive polymer shell. Doxorubicin is loaded onto the surface of the last coating layer, and a high loading efficiency is obtained. The nano-carriers are characterized with FTIR, dynamic light scattering, Zeta potential, In vitro hyperthermia, and vibrating sample magnetometry. The in vitro drug release experiments confirm that a small amount of doxorubicin is released at body temperature and physiological pH, whereas a high drug release is obtained at acidic tumor pH under hyperthermia conditions (43 °C). The core/shell bi-magnetic nano-carriers facilitate controllable release of doxorubicin as effect of induced thermo-and pHresponsiveness of the polymer when are subjected to an high-frequency alternating magnetic field at acidic pH; thereby the drug release rate is controlled using on-off cycles of the applied field. iii KURZFASSUNG Diese Arbeit befasst sich mit der speziellen Gestaltung von multifunktionalen magnetischen Nanopartikeln für diverse biomedizinische Anwendungen. Verschiedene Formen der Kern/Schale-bimagnetischen Nanopartikel wurden durch die "seed-mediated growth" Methode synthetisiert, und die strukturellen und magnetischen Eigenschaften dieser Formen untersucht. Die Versuchsergebnisse haben gezeigt, dass die Kern/Schale-Nanopartikel eine höhere spezifische Energiea als reine Kern Partikel haben. Für die Drug Delivery Anwendung wird die Oberfläche der magnetischen Nanopartikel auf unterschiedlichen Wege (Diels-Alder-Reaktion und Layer-by-Layer-Verfahren) funktionalisiert. Dazu wurde an ein neuartiges bifunktionelles thermosensitives System, welches aus furanbeschichteten Kern/Schale bi-magnetischen Nanopartikel besteht, N-(2-Carboxyethyl) maleimid durch Diels-Alder Reaktion angebunden. Mit der Anbindung des chemotherapeutischen Doxorubicins an die Oberfläche der nano-carriers wurde ein hohe Beladungsgrad von 92% erzielt. Dieses System mit hoher Ansprechempfindlichkeit auf hochfrequente äußere magnetische Wechselfelder zeigt eine sehr gute therapeutische Wirksamkeit in der Hyperthermie und als Drug-Delivery-System bei relativ niedrigen Temperaturen (50 °C). Ein schaltbare Wirkstofffreisetzung wird durch Beschichtung der Kern/Schale bimagnetischen Nanopartikel mit einer pH-und temperaturempfindlichen Polymerschicht ermöglicht. Mit der Anbringung des Doxorubicins auf die Oberfläche der letzten Beschichtung wurde eine hohe Beladungseffizienz erhalten. Diese System wird mittels dynamischer Lichtstreuung, FT-IR-, In-vitro-Hyperthermie, UV/Vis-und Fluoreszenz-Spektroskopie, sowie Zetapotential-Messungen charakterisiert. Die in vitro Wirkstofffreisetzungsversuche bestätigen, dass eine kleine Menge von Doxorubicin bei Raumtemperatur und physiologischen pH freigesetzt wird, während eine hohe Wirkstofffreisetzung bei sauren pH-Werten in Tumoren unter Hyperthermi Bedingungen (43 ° C) erhalten wird. Die Kern/Schale bimagnetischen Nanopartikel erleichtern die Freisetzung von Doxorubicin infolge der induzierten thermound pH-Ansprechempfindlichkeit des Polymers, wenn sie in einem hochfrequenten magnetischen Wechselfeld einem sauren pH-Wert ausgesetzt werden. Dadurch wird die Arzneimittelfreisetzungsrate anhand on-off-Zyklen des angelegten Feldes gesteuert. iv