scholarly journals Maghemite nanoparticles coated by methacrylamide-based polymer for magnetic particle imaging

2021 ◽  
Vol 23 (2) ◽  
Author(s):  
Vít Herynek ◽  
Michal Babič ◽  
Ondřej Kaman ◽  
Hana Charvátová ◽  
Mariana Veselá ◽  
...  
Keyword(s):  
Mössbauer Spectroscopy ◽  
Sodium Hypochlorite ◽  
Magnetic Particle ◽  
Colloidal Stability ◽  
Mossbauer Spectroscopy ◽  
Hydrodynamic Diameter ◽  
Mößbauer Spectroscopy ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

AbstractA wise selection of tracers is critical for magnetic particle imaging (MPI). Most of the current tracers are based on superparamagnetic iron oxide nanoparticles (SPIONs) with a suitable coating. We prepared maghemite cores (γ-Fe2O3) by coprecipitation of Fe(II) and Fe(III) salts with ammonium hydroxide followed by oxidation with hydrogen peroxide and stabilization as an anionic (γ-Fe2O3⊖) or cationic colloid (γ-Fe2O3⨁). The cores were coated by poly(N-(2-hydroxypropyl)methacrylamide)-co-N-[2-(hydroxyamino)-2-oxo-ethyl]-2-methyl-prop-2-enamide. The particles were characterized by dynamic light scattering, transmission electron microscopy, X-ray diffraction, Mössbauer spectroscopy, tested in vitro in a field-free point MPI scanner, and compared to nanoparticles prepared by oxidation with sodium hypochlorite and to the commercially available Resovist®. The cores had an average diameter of 8.0 nm (γ-Fe2O3⨁) and 8.7 nm (γ-Fe2O3⊖); the hydrodynamic diameter was 88 nm. Zeta potential values for both positively charged (+52 mV) and negatively charged particles (–60 mV) provided for good colloidal stabilization. Spinel structure of maghemite was confirmed by Mössbauer spectroscopy. The uncoated γ-Fe2O3⨁ particles yielded an MPI signal lower (by 16 %) than Resovist; the coated ones reached 88 % of the Resovist signal. Anionic γ-Fe2O3⊖ particles reached a higher (uncoated particles, by 15 %) or comparable (coated ones) signal relative to Resovist with a substantially lower signal dispersion. Control particles prepared by oxidation with sodium hypochlorite scored the weakest results. To conclude, a suitable size, narrow size distribution, and colloidal stability predispose the synthetized particles for use as a tracer for MPI. The anionic particles provided a higher signal with a lower dispersion than commercial tracers.

scholarly journals Study of the Structural and Magnetic Properties of COFE2O4 Nanoparticles for Therapeutic Agent for Cancer Therapy

2021 ◽  
pp. 69-75
Author(s):  
M Khairul Islam ◽  
M Nasir Uddin Khan ◽  
M Shahinuzzaman
Keyword(s):  
Particle Size ◽  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Hydrodynamic Diameter ◽  
Cofe2o4 Nanoparticles ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Set Up ◽  
Co Precipitation

The cobalt ferrite (CoFe2O4) nanoparticles were synthesized by chemical co-precipitation technique and characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and Mössbauer spectroscopy. The CoFe2O4 nanoparticles coated with biocompatible chitosan at different concentrations to produce homogeneous suspensions were also characterized by dynamic light scattering (DLS) and hyperthermia set-up. XRD data of the sample explored the particle size near about 7 nm in as-dried condition. TEM micrograph of bare CoFe2O4 nanoparticles provided the particle size nearly too about 8 nm which is in good agreement with the XRD data. This particle size after coating with chitosan became 14 nm. EDX results of this sample confirmed its nano dimension with spinel structure. VSM results of the sample in as-dried condition showed the ferromagnetic character which has been beyond proved by Mössbauer spectroscopy. The hydrodynamic diameter (Hd) and polydispersity index (PDI) of the chitosan-coated samples also provided promising results. The samples were tested for their induction heating properties with an RF magnetic field of 20 mT and a frequency of 342 kHz. We also studied therapeutic efficiency in-vitro on 9L gliosarcoma cancer cells, which revealed > 98% of mortality through hyperthermia protocol with the same RF field and frequency using chitosan-coated CoFe2O4nanoparticles. GUB JOURNAL OF SCIENCE AND ENGINEERING, Vol 7, Dec 2020 P 69-75

scholarly journals Navigation of a magnetic micro-robot through a cerebral aneurysm phantom with magnetic particle imaging

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anna C. Bakenecker ◽  
Anselm von Gladiss ◽  
Hannes Schwenke ◽  
André Behrends ◽  
Thomas Friedrich ◽  
...  
Keyword(s):  
Magnetic Fields ◽  
Cerebral Aneurysm ◽  
Magnetic Particle ◽  
Cerebral Aneurysms ◽  
Localization Accuracy ◽  
Magnetic Particle Imaging ◽  
Micro Robot ◽  
Life Threatening ◽  
Particle Imaging

AbstractCerebral aneurysms are potentially life threatening and nowadays treated by a catheter-guided coiling or by a neurosurgical clipping intervention. Here, we propose a helically shaped magnetic micro-robot, which can be steered by magnetic fields in an untethered manner and could be applied for a novel coiling procedure. This is shown by navigating the micro-robot through an additively manufactured phantom of a human cerebral aneurysm. The magnetic fields are applied with a magnetic particle imaging (MPI) scanner, which allows for the navigation and tomographic visualization by the same machine. With MPI the actuation process can be visualized with a localization accuracy of 0.68 mm and an angiogram can be acquired both without any radiation exposure. First in-vitro phantom experiments are presented, showing an idea of a robot conducted treatment of cerebral aneurysms.

scholarly journals Lactoferrin conjugated iron oxide nanoparticles for targeting brain glioma cells in magnetic particle imaging

Nanoscale ◽  
2015 ◽  
Vol 7 (40) ◽  
pp. 16890-16898 ◽  
Author(s):  
Asahi Tomitaka ◽  
Hamed Arami ◽  
Sonu Gandhi ◽  
Kannan M. Krishnan
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Magnetic Particle ◽  
Glioma Cells ◽  
Oxide Nanoparticles ◽  
Brain Glioma ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

Monodisperse lactoferrin conjugated iron oxide nanoparticles were synthesized and evaluated forin vitroglioma imaging using Magnetic Particle Imaging (MPI).

scholarly journals Complex Relationship Between Signal Intensity Properties in Magnetic Particle Imaging (MPI) and Iron Oxide Nanoparticle Degradation

2020 ◽  
Author(s):  
Julia Guzy ◽  
Shatadru Chakravarty ◽  
Foster Buchanan ◽  
Haoran Chen ◽  
Jeffrey M. Gaudet ◽  
...  
Keyword(s):  
Magnetic Particle ◽  
Imaging Modality ◽  
Quantitative Imaging ◽  
Superparamagnetic Nanoparticles ◽  
Iron Oxide Nanoparticle ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

Magnetic particle imaging (MPI) is an exciting new biomedical imaging technology that uses superparamagnetic nanoparticles as an imaging tracer. MPI is touted as a quantitative imaging modality but MPI signal properties have never been characterized for nanoparticles undergoing biodegradation. Here we characterize the nature of the MPI signal properties as a function of degradation of various magnetic particle formulations. We show that MPI signal properties can increase or decrease as a function of nanoparticle formulation and chemical environment and that long-term in vitro experiments only roughly approximate long-term in vivo MPI signal properties. Data are supported by electron microscopy of nanoparticle degradation. Knowledge of MPI signal property changes during nanoparticle degradation will be critical in design and interpretation of all MPI experiments. Further, we demonstrate for the first time, an environmentally sensitive MPI contrast mechanism opening the door to smart contrast paradigms in MPI.<br>

scholarly journals Complex Relationship Between Signal Intensity Properties in Magnetic Particle Imaging (MPI) and Iron Oxide Nanoparticle Degradation

2020 ◽  
Author(s):  
Julia Guzy ◽  
Shatadru Chakravarty ◽  
Foster Buchanan ◽  
Haoran Chen ◽  
Jeffrey M. Gaudet ◽  
...  
Keyword(s):  
Magnetic Particle ◽  
Imaging Modality ◽  
Quantitative Imaging ◽  
Superparamagnetic Nanoparticles ◽  
Iron Oxide Nanoparticle ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

Magnetic particle imaging (MPI) is an exciting new biomedical imaging technology that uses superparamagnetic nanoparticles as an imaging tracer. MPI is touted as a quantitative imaging modality but MPI signal properties have never been characterized for nanoparticles undergoing biodegradation. Here we characterize the nature of the MPI signal properties as a function of degradation of various magnetic particle formulations. We show that MPI signal properties can increase or decrease as a function of nanoparticle formulation and chemical environment and that long-term in vitro experiments only roughly approximate long-term in vivo MPI signal properties. Data are supported by electron microscopy of nanoparticle degradation. Knowledge of MPI signal property changes during nanoparticle degradation will be critical in design and interpretation of all MPI experiments. Further, we demonstrate for the first time, an environmentally sensitive MPI contrast mechanism opening the door to smart contrast paradigms in MPI.<br>

scholarly journals Magnetic Particle Imaging: In vitro Signal Analysis and Lumen Quantification of 21 Endovascular Stents

2021 ◽  
Vol Volume 16 ◽  
pp. 213-221
Author(s):  
Franz Wegner ◽  
Anselm von Gladiss ◽  
Julian Haegele ◽  
Ulrike Grzyska ◽  
Malte Maria Sieren ◽  
...  
Keyword(s):  
Signal Analysis ◽  
Magnetic Particle ◽  
Endovascular Stents ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

scholarly journals Complex Relationship Between Signal Intensity Properties in Magnetic Particle Imaging (MPI) and Iron Oxide Nanoparticle Degradation

2020 ◽  
Author(s):  
Julia Guzy ◽  
Shatadru Chakravarty ◽  
Foster Buchanan ◽  
Haoran Chen ◽  
Jeffrey M. Gaudet ◽  
...  
Keyword(s):  
Magnetic Particle ◽  
Imaging Modality ◽  
Quantitative Imaging ◽  
Superparamagnetic Nanoparticles ◽  
Iron Oxide Nanoparticle ◽  
Magnetic Particle Imaging ◽  
Particle Imaging

Magnetic particle imaging (MPI) is an exciting new biomedical imaging technology that uses superparamagnetic nanoparticles as an imaging tracer. MPI is touted as a quantitative imaging modality but MPI signal properties have never been characterized for nanoparticles undergoing biodegradation. Here we characterize the nature of the MPI signal properties as a function of degradation of various magnetic particle formulations. We show that MPI signal properties can increase or decrease as a function of nanoparticle formulation and chemical environment and that long-term in vitro experiments only roughly approximate long-term in vivo MPI signal properties. Data are supported by electron microscopy of nanoparticle degradation. Knowledge of MPI signal property changes during nanoparticle degradation will be critical in design and interpretation of all MPI experiments. Further, we demonstrate for the first time, an environmentally sensitive MPI contrast mechanism opening the door to smart contrast paradigms in MPI.<br>

scholarly journals Effect of key parameters on synthesis of superparamagnetic nanoparticles (SPIONs)

2016 ◽  
Vol 2 (1) ◽  
pp. 529-532
Author(s):  
Ankit Malhotra ◽  
Felix Spieß ◽  
Corinna Stegelmeier ◽  
Christina Debbeler ◽  
Kerstin Lüdtke-Buzug
Keyword(s):  
Cross Correlation ◽  
Magnetic Particle ◽  
Amplitude Spectrum ◽  
Correlation Spectroscopy ◽  
Superparamagnetic Nanoparticles ◽  
Hysteresis Curve ◽  
Hydrodynamic Diameter ◽  
Magnetic Particle Imaging ◽  
Co Precipitation ◽  
Particle Imaging

AbstractThere are various methods to synthesize superparamagnetic nanoparticles (SPIONs) useful for MPI (magnetic particle imaging) and in therapy (Hypothermia) such as co-precipitation, hydrothermal reactions etc. In this research, the focus is to analyse the effects of crucial parameters such as effect of molecular mass of dextran and temperature of the co-precipitation. These parameters play a crucial role in the inherent magnetic properties of the resulting SPIONs. The amplitude spectrum and hysteresis curve of the SPIONs is analysed with MPS (magnetic particle spectrometer). PCCS (photon cross-correlation spectroscopy) measurements are done to analyse the size distribution of hydrodynamic diameter the resulting SPIONs.

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