• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.27-27
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• 2017

Biocompatible capsules have recently been highlighted as novel delivery platforms of any "materials" (e.g., drug, food, agriculture pesticide) to address current problems of living systems such as humans, animals, and plats in academia and industry for agriculture, biological, biomedical, environmental, food applications. For example, biocompatible alginate capsules were proposed as a delivery platform of biocontrol agents (e.g., bacterial antagonists) for an alternative to antibiotics, which will be a potential strategy in future agriculture. Here, we proposed a new platform based on biocompatible alginate capsules that can control the movements as an active target delivery strategy for various applications including agriculture and biological engineering. We designed and fabricated large scale biocompatible capsules using alginates and custom-made nozzles as well as gelling solutions. To develop the active target delivery platforms, we incorporated the iron oxide nanoparticles in the large scale alginate capsules. It was found that the sizes of large scale alginate capsules could be controlled via various working conditions such as concentrations of alginate solutions and iron oxide nanoparticles. As a proof of concept work, we showed that the iron oxide particles-incorporated large scale alginate capsules could be moved actively by the magnetic fields, which would be a strategy as active target delivery platforms for agriculture and biological engineering (e.g., controlled delivery of agriculture pesticides and biocontrol agents).

• Journal of the Korean Society of Radiology
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• v.8 no.6
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• pp.325-332
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• 2014

Metallic nanoparticles have attractive properties in biomedical applications such as diagnostics and therapeutics. Cross linked dextran coated iron oxide nanoparticles (SPIONs) and silica coated gadolinium oxide nanoparticles (SPGONs) have been synthesized as a radiosensitizer in the proton beam cancer therapy. The dextran and silicaused for the protective moieties on the SPIONs and SPGONs respectively. Size distributions of synthesized nanoparticles were confirmed 3~5 nm for SPIONs and 30~100 nm for SPGONs by transmission electron microscope (TEM). Cell survival fraction measurement and Western blot assay were performed to evaluate the radiosensitization effects of synthesized radiosensitizer. The calculated radiosensitization of SPIONs and SPGONs at 90 % cell death from the measured cell survival curves were 1.23 and 1.03 respectively. Western blotting results also show the same consistent results that the amount of released cytochrome c from mitochondria was considerably increased for the cancer cells taken up SPIONs.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1162-1165
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• 2004

Size and crystalline phase changes of $Fe_{2}O_{3}$ nanoparticles formed in a $H_{2}/O_{2}$ flame have been investigated. At flame temperatures below $1350^{\circ}C$, the mean particle size increased monotonously with the distance from the burner edge; but in high-temperature flames above $1650^{\circ}C$, it suddenly decreased from 20 nm to ${\sim}3$ nm with the distance from the burner edge. The results of X-ray diffraction and HRTEM showed that this sudden reduction of the size of nanoparticles was accompanied by a partial phase transformation from ${\gamma}$-$Fe_{2}O_{3}$ into ${\alpha}$-$Fe_{2}O_{3}$. We suggest the structural instability due to ${\gamma}-$ to ${\alpha}-phase$ transformation as a mechanism for a rapid fragmentation of 20 nm particles into 3 nm ones.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.424-425
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• 2006

The effects of reaction temperature and precursor concentration on the microstructure and magnetic properties of ${\gamma}-Fe_2O_3$ nanoparticles synthesized as final products of iron acetylacetonate in chemical vapor condensation (CVC) were investigated. Pure ${\gamma}-Fe_2O_3$ phase was obtained at temperature above $900^{\circ}C$ and crystallite size of ${\gamma}-Fe_2O_3$ nanoparticles decreased with lowering precursor concentration. Also, the coercivity decreases with decreasing crystallite size of nanopowder. The lowest coercivity was 7.8 Oe, which was obtained from the ${\gamma}-Fe_2O_3$ nanopowder sample synthesized at precursor concentration of 0.3M. Then, the crystallite size of ${\gamma}-Fe_2O_3$ nanoparticles was 8.8 nm.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.98-103
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• 2009

Superparamagnetic iron oxide nanoparticles (SPIOs)-embedded chitosan microspheres were developed for magnetic resonance (MR)-traceable embolotherapy. SPIOs-loaded chitosan microspheres were prepared by emulsion and cross-linking technique and 100-200 ${\mu}m$ sized spherical microsparticles were obtained. Loading efficacy and loading amount of SPIOs in microspheres were about 40% and 0.26-0.32%, respectively, when measured by inductively coupled plasma atomic emission spectroscopy. Within 30 days, about 60% of the incorporated SPIOs were released from low cross-linked microspheres, whereas only about 40% of SPIOs was released from highly cross-linked microspheres. Highly cross-linked microspheres were more efficient for lower degree of swelling leading to secure entrapment of SPIOs in matrix. Prepared novel embolic microspheres are expected to be practically applicable for traceable embolotherapy with high resolution and sensitivity through magnetic resonance imaging (MRI).

• Advances in nano research
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• v.8 no.2
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• pp.95-102
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• 2020

In this work the properties of iron oxide magnetic nanoparticles (MNPs) synthesized by electrochemical method using different water-alcohol proportions and alcohols have been investigated. The syntheses were carried out using 99% iron foils acting electrodes in a 0.04 M NaCl solutions at room temperature applying 22 mAcm^-2 on the working electrode, mostly obtaining magnetite nanoparticles. The impact of the electrolyte in the size of the synthesized MNPs has been evaluated by transmission electron microscopy (TEM), X-ray diffraction (XRD), chronopotentiometric studies, and magnetic characterization. The results have shown that nanoparticles can be obtained in the range of 6 to 26 nm depending on the type of alcohol and the proportions in the mixture of water-alcohol. The same trend has been observed for all alcohols. As the proportion of these in the medium increases, the nanoparticles obtained are smaller in size. This trend is maintained until a certain proportion of alcohol: 50% for methanol, and 60% for the rest of alcohols, proportions where obtaining a single phase of magnetite is not favored.

• Korean Journal of Veterinary Research
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• v.54 no.4
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• pp.245-252
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• 2014

This study was investigated the change of concentration and toxicity of thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION) on tissues of Sprague-Dawley rats. TCL-SPION at the dose of 15 mg/kg body weight was intravenously injected into the tail vein of the male Sprague-Dawley rats. The fate of TCL-SPION in serum, urine and tissues was observed during 28 days. Serum iron level was maximal at 0.25 h post-injection and gradually declined thereafter. In addition, the sinusoids of liver and the red pulp area of spleen were mainly accumulated iron from 0.5 h to 28-day post-injection. In kidney, iron deposition was detected in the tubular area until 0.5 h after injection. Malondialdehyde concentration in the liver slightly increased with time and was not different with that at zero time. In the liver and spleen, TNF-${\alpha}$ and IL-6 levels of TS treated with TCL-SPION were not different with those of the control during the experimental period. From the results, TCL-SPION could stay fairly long-time in certain tissues after intravenous injection without toxicity. The results indicated that TCL-SPION might be useful and safe as a contrast for the diagnosis of cancer or a carrier of therapeutic reagents to treat diseases.

• Journal of Pharmacopuncture
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• v.23 no.3
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• pp.165-172
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• 2020

Objectives: In the past few years, herbal medicines have gained popularity over synthetic drugs because of their natural source and minimal side effects which has led to a tremendous growth of phytopharmaceuticals usage. With the development of nanotechnology, it provides alternative approaches to overcome several limitations using nano-formulations. In spite of considerable quantity of antianemic preparations with different iron forms available, currently additives are used and represented in modern pharmaceutical market. Iron deficiency anemia is a major global public health problem which particularly affects pregnant women, children and elderly persons. The situation is complicated because of disadvantages and drug side effects from existing antianemic medicines. There is a great demand for the development of new antianemic preparations. Green synthesis of iron oxide nanoparticles, possess high potential in this field. Methods: Our study focuses on developing green synthesis of iron oxide nanoparticles (IONPs) of 10-50 nm with spherical shape where different dosages were used -1 mg/kg, 10 mg/kg and 100 mg/kg for exposure in Wistar albino female rats for 28 days. The toxicity was assessed using various parameters such as measurements of the rat body and organ mass, hematology, biochemical evaluation and histopathological examinations. Results: No significant differences were observed in body and organ weights. Hematological indices also indicated no significant differences whereas biochemical factors showed increase in levels of direct bilirubin and globulin of medium as well as high dose and SGPT levels were increased only in high dose. The major organs (heart, kidney and liver) showed histopathological alterations in 10 and 100 mg/kg whereas brain showed only in 100 mg/kg. Conclusion: The toxicity of IONPs was found to be more significant when the concentration was increased; however, low doses can be used for further investigation as an antianemic preparation.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.3957-3962
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• 2012

Iron-oxide nanoparticles (IONs) with biocompatible coatings are the only nanostructural materials which have been approved by the FDA for clinical use. Common biocompatible coatings such as hydrocarbons, polymers, and silica have profound influences on critical characteristics of IONs. Recently, amino acids were introduced as a novel biocompatible coating. In the present study, the effects of amino acids on IONs synthesis and characteristics have been evaluated. Magnetite nanoparticles with L-arginine and L-lysine coatings were synthesised by a coprecipitation reaction in aqueous solvent and their characteristics were compared with naked magnetite nanoparticles. The results showed that amino acids can be a perfect coating for IONs and would increase particle stability without any significant effects on the critical properties of nanoparticles such as particle size and magnetization saturation value.

• Polymer(Korea)
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• v.36 no.5
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• pp.586-592
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• 2012

Iron oxides ($Fe_3O_4$) are metabolically secreted after endocytosed by cells, indicating no cytotoxicity. Therefore, they are widely used as a contrast agent before photographing of magnetic resonance imaging. In this study, iron oxide nanoparticles are synthesized by the co-precipitation method and subsequently immobilized with a homing peptide (AP), which specifically interacts with interleukin-4 receptor located on the membrane of endothelial and bladder cancer cells. The size of AP-immobilized iron oxide particle is about 39 nm. Intracellular uptake of the AP-immobilized iron oxide nanoparticles was investigated using bladder cancer cells and fibroblasts as the control. As the result, the nanoparticles are specificially uptaken by bladder cancer cells. However, the nanoparticles are not specificially uptaken by fibroblast. It could be said that the AP-immobilized iron oxide nanoparticles have a potential to be used as a contrast agent for early diagnosis of cancer.