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ABSTRACT: A methotrexate (MTX)-loaded layered double hydroxide (LDH) nanoparticle system was synthesized by intercalating MTX into the interlayer spaces of LDH. In vivo pharmacokinetic study demonstrated that the MTX-LDH hybrid had similar kinetic behaviors as free MTX, showing a rapid decline in the plasma MTX level, with characteristics of a biexponential function. However, the hybrid system remarkably suppressed tumor growth in human osteosarcoma-bearing mice compared to an equivalent amount of free MTX. Using MTX-LDH nanoparticles, a significantly high amount of MTX was delivered to target tumor tissue, whereas a low level was found in normal tissues. Moreover, LDH nanocarriers did not accumulate in any specific tissue nor cause acute toxicity up to the applied dose for the hybrid system. These results suggest that the MTX-LDH nanohybrid system has great potential as an anti-cancer drug with enhanced in vivo anti-tumor activity and bioavailability in target tumor tissue along with reduced side effects.
Current pharmaceutical design 03/2013; · 4.41 Impact Factor
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ABSTRACT: In this review, we are going to demonstrate the recent progresses in inorganic nanomaterial-based nanomedicines and their labeling for effective biological imaging. Nanomaterials which are classified according to their dimensionality, from zero- to three-dimensions can be utilized as nanomedicines including drug delivery, therapy and diagnosis. In the following section, the labeling of nanomaterials with various contrasting agent is introduced. Various labeling agent like fluorescence, quantum dots, upconversion nanoparticles, magnetic particles and radioisotopes can be tagged on nanomaterials for effective imaging such as optical, magnetic resonance, computed tomography, positron emission tomography and etc. The labeling of contrasting agent on nanomedicine can be summarized into intercalation, surface modification, embedment and combination how and where the label is tagged. Through these approaches, multimodal biological imaging and multifunctional nanomedicine could besuggested.
Current topics in medicinal chemistry 02/2013; · 4.47 Impact Factor
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ABSTRACT: This review outlines research and patents relating to the use of inorganic nanomaterial, layered double hydroxide, as nanocontainers for drug delivery and gene reservoirs. Various intercalative synthetic routes including coprecipitation, ion exchange, reconstruction and exfoliation-reassembly have been explored to incorporate drug or gene molecules. Its unique two-dimensional structure allows layered double hydroxide to act as a nanospace for the stabilization, targeted delivery or controlled release of gene or drug molecules. Intercalative hybrid nanomaterials have uses such as pharmaceutically active ingredients, in oral- or cellular delivery systems, cosmetic ingredients, molecular coding units and etc. Toxicological studies have found layered double hydroxides to be biocompatible compared with widely used nanoparticles such as iron oxide, silica, and single-walled carbon nanotubes. Due to their versatile functionality and biocompatibility, layered double hydroxides have been widely studied and their applicability can be expanded to other nanoparticle based bio-medical applications.
Recent patents on nanotechnology. 06/2012;
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02/2012; , ISBN: 9783527610419
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Miri Baek,
Hae-Eun Chung,
Jin Yu,
Jung-A Lee,
Tae-Hyun Kim, Jae-Min Oh,
Won-Jae Lee,
Seung-Min Paek,
Jong Kwon Lee,
Jayoung Jeong,
Jin-Ho Choy,
Soo-Jin Choi
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ABSTRACT: This study explored the pharmacokinetics, tissue distribution, and excretion profile of zinc oxide (ZnO) nanoparticles with respect to their particle size in rats.
Two ZnO nanoparticles of different size (20 nm and 70 nm) were orally administered to male and female rats, respectively. The area under the plasma concentration-time curve, tissue distribution, excretion, and the fate of the nanoparticles in organs were analyzed.
The plasma zinc concentration of both sizes of ZnO nanoparticles increased during the 24 hours after administration in a dose-dependent manner. They were mainly distributed to organs such as the liver, lung, and kidney within 72 hours without any significant difference being found according to particle size or rat gender. Elimination kinetics showed that a small amount of ZnO nanoparticles was excreted via the urine, while most of nanoparticles were excreted via the feces. Transmission electron microscopy and x-ray absorption spectroscopy studies in the tissues showed no noticeable ZnO nanoparticles, while new Zn-S bonds were observed in tissues.
ZnO nanoparticles of different size were not easily absorbed into the bloodstream via the gastrointestinal tract after a single oral dose. The liver, lung, and kidney could be possible target organs for accumulation and toxicity of ZnO nanoparticles was independent of particle size or gender. ZnO nanoparticles appear to be absorbed in the organs in an ionic form rather than in a particulate form due to newly formed Zn-S bonds. The nanoparticles were mainly excreted via the feces, and smaller particles were cleared more rapidly than the larger ones. ZnO nanoparticles at a concentration below 300 mg/kg were distributed in tissues and excreted within 24 hours. These findings provide crucial information on possible acute and chronic toxicity of ZnO nanoparticles in potential target organs.
International Journal of Nanomedicine 01/2012; 7:3081-97. · 3.13 Impact Factor
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ABSTRACT: This tutorial review describes a new class of data processing system that applies information theory at the molecular level. We also summarize the recent multidisciplinary advances in biotechnology and nanotechnology that have facilitated the development of reliable nano-level code systems. After a brief introduction of information theory, we present possible ways to adapt this concept to the molecular world. This review explains the requirements and solutions for each step necessary to apply a nano code system to real products. Finally, we introduce a designed nano code system for agricultural products as one example of the many possible applications for nano codes.
Chemical Society Reviews 02/2011; 40(2):583-95. · 28.76 Impact Factor
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ABSTRACT: Intracellular drug delivery of layered double hydroxide (LDH) nanocarriers have been examined in human osteosarcoma Saos-2 cell culture line by both electron and confocal microscopies. For transmission electron microsopic (TEM) study, LDHs and anticancer drug, methotrexate (MTX) loaded LDHs were synthesized and the particle size was controlled. From the scanning electron microscopic (SEM) studies, morphologies of LDH nanoparticle and its MTX intercalated form were proven to be platelike hexagonal with an average size of approximately 150 nm. In order to understand the cellular penetration behavior, both nanoparticles were treated to human osteosarcoma Saos-2 cell culture lines and the cellular uptake pattern with respect to incubation time was observed by TEM and SEM. We observed that the nanoparticles are attached at the cellular membrane at first and then internalized into the cells via endocytosis within 1 h. Then are located in the intracellular vacuole (endosome). In order to examine the intracellular drug delivery mechanism of LDH nanoparticles, fluorescein 5-isothiocyanate (FITC) labeled MTX was intercalated into LDH and treated on Saos-2 cells. Laser scanning confocal microscopic studies revealed that the FITC-MTX molecules were first internalized with LDH nanocarriers via endocytosis, and located in endosome to deliver loaded drug to target cellular organ. It was, therefore, concluded that LDH could play a role as drug delivery nanocarriers.
Journal of Nanoscience and Nanotechnology 02/2011; 11(2):1632-5. · 1.56 Impact Factor
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ABSTRACT: The fabrication of layered nanomaterials, such as inorganic-inorganic, organic-inorganic, and bioinorganic nanohybrids has been demonstrated through controlled lattice engineering techniques including intercalation, exfoliation-reassembling, and pillaring reactions. Such a lattice engineering method gives rise to an almost unlimited set of new hybrid compounds with a large spectrum of desirable properties. Due to the unique two-dimensional structures and properties, various kinds of functional nanohybrid materials can be utilized as photocatalysts, electrode materials, superconducting thin films, gas separation membranes, drug-delivery systems, and biomolecule reservoirs.
Chemistry - An Asian Journal 02/2011; 6(2):324-38. · 4.50 Impact Factor
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ABSTRACT: We have investigated the diffusion of various solvents on nanoporous membranes with various pore size and surface energy. We have modified the size of pore channel and surface energy of porous membrane through grafting different sized alkyl chain on inorganic membranes. Typically, disc type zirconia membranes with pore size of 3 nm and silica ones with 1 nm pore were purchased from Inocermic Co. Ltd. (Germany), and the surface and pore channel was modified by either octyltriethoxysilane (OTS) with chain length approximately 1 nm or pentyltriethoxysilane (PTS) with chain length approximately 0.5 nm. The water contact angles of both OTS and PTS grafted membrane were larger than 100 degrees indicating the hydrophobically modified surface. Contact angles of hydrophilic and hydrophobic solvents were also examined to obtain exact surface energy (gamma(sv)) of grafted membrane, and the values were determined to be 56.3, 45.3, and 42.2 mN/m for ungrafted, PTS- and OTS-grafted membrane, respectively. The solvent diffusion patterns were evaluated by measuring the concentration gradient of small dye molecule, azobenzene. The diffusion coefficients of various solvents were measured on the basis of Fick's diffusion law. It was concluded that the diffusivity is dependent on the pore size for solvent with low surface tension and on the gamma(sv) value for solvent with high surface tension.
Journal of Nanoscience and Nanotechnology 02/2011; 11(2):1656-9. · 1.56 Impact Factor
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ABSTRACT: A chemically well-defined Bio Core@Inorganic Shell nanohybrid, which consists of rationally designed DNA molecule core with a size of ∼100 nm and spherical inorganic nanoshell with an overall thickness of ∼10 nm reassembled with exfoliated layered metal hydroxide (MH nanosheets), is prepared. The DNA encapsulation and its release, due to the pH-dependent solubility of the MH nanoshell, plays a crucial role in maximizing the stability of base sequence-manipulated and probe-functionalized DNA molecules with designed information. The present DNA Core@MH Shell nanohybrid can provide wide bioinspired applications converged with nanotechnology, such as an advanced gene delivery system and a biomedical diagnostics, tracing/collection/sensing system for DNA-based information.
Journal of the American Chemical Society 12/2010; 132(47):16735-6. · 9.91 Impact Factor
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08/2010: pages 163 - 187; , ISBN: 9780470661406
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ABSTRACT: Nanoencapsulation technology has a diverse range of applications, including drug-delivery systems (DDS) and cosmetic and chemical carriers, because it can deliver various bio- and organic-molecules and improve their stabilities. Conjugated linoleic acid (CLA) has health benefits, including being an anticancer agent, but it decreases flavor due to volatiles from oxidation. To improve the stability of CLA for food applications, nanoencapsulated CLA was synthesized for use in zinc basic salt (ZBS) and characterized by powder X-ray diffractometry, thermogravimetric analysis (TGA), elemental CHN analysis, inductively coupled plasma (ICP) analysis, UV/VIS spectroscopy, and FTIR spectroscopy. The thermal stability of nanoencapsulated CLA at 180 degrees C, a temperature similar to that used in cooking, was analyzed by gas chromatography. The gallery height of nanoencapsulated CLA was determined to be approximately 26 A through powder X-ray diffractometry; therefore, the CLA molecules were closely packed with zig-zag form between the intracrystalline spaces of nano particles. Elemental CHN analysis and ICP data determined the chemical composition of nanoencapsulated CLA to be Zn(4.86)(OH)(8.78)(CLA)(0.94). By TGA, it was determined about 45% (wt/wt) of weight loss corresponded to CLA, which is good agreement with the 42.13% (wt/wt) determined from high-performance liquid chromatography (HPLC) and elemental CHN analysis. UV/VIS spectroscopy and Fourier-transformed infrared (FTIR) spectroscopy showed encapsulated CLA maintained a conjugated diene structure, supporting the presence of CLA. Nanoencapsulation improved the thermal stability of CLA by about 25%, compared to pristine CLA. Practical Application: This system can be used for protection of encapsulated negatively-charged food ingredients from thermal processing.
Journal of Food Science 08/2010; 75(6):N63-8. · 1.66 Impact Factor
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ABSTRACT: We have developed new hybrid systems consisting of anticancer drugs such as methotrexate (MTX) or 5-fluorouracil (5-FU) and two-dimensional inorganic delivery carrier like layered double hydroxide (LDH). Such an inorganic vector with biocompatible metal ions can be used to overcome toxicity, immunogenecity and poor integration capacity, which are critical problems caused by conventional viral vectors, cationic liposomes and polymers. Moreover, the intercellular mechanism of LDH nanoparticles is primarily related to clathrin-mediated endocytosis, resultihg in effective delivery and eventually enhancing drug efficacy. In this report, the effect of LDH intercalated with 5-Fu (5-Fu-LDH) was evaluated in whole animal by studying pharmacokinetic behavior and tissue distribution. The results showed that 5-Fu-LDH exhibited favorable blood clearance profiles compared to free 5-Fu, such as sustained drug release, prolonged drug half-life, and increased drug accumulation in target tumor tissue. Furthermore, LDH nanoparticles were rapidly excreted from the body and not accumulated in the organs after administration as 5-Fu-LDH. Therefore, the hybrid system can be promising anticancer chemotherapy agent for tumor targeting with biocompatibility.
Journal of Nanoscience and Nanotechnology 04/2010; 10(4):2913-6. · 1.56 Impact Factor
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ABSTRACT: Because candidiasis is usually associated with immunosuppression, candida arthritis in an immunocompetent patient is rare. The symptoms of candidiasis are similar to bacterial infections, tuberculosis, and autoimmune diseases. In our patient with no predisposing factors, candida arthritis was initially excluded because the probability of occurrence was low. The patient had no leukocytosis, the acid-fast bacteria (AFB) stain was negative, and the autoimmune antibody screen was negative. After Candida parapsilosis was cultured in the synovial fluid, the patient was treated with amphotericin B (0.7 mg/kg/day) and oral fluconazole (400 mg/day). The treatment was successful and there were no side effects of the medications.
The Open Rheumatology Journal 01/2010; 4:7-9.
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Advanced Functional Materials 03/2009; 19(10):1617 - 1624. · 10.18 Impact Factor
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ABSTRACT: Layered double hydroxides, a class of anionic nanoclays, have emerged as drug delivery carriers characterized by an effective uptake mechanism via clathrin-mediated endocytosis and high reservoir capacity. In the present review, the efficacy of an anti-cancer drug with ceramic nanocarriers, i.e. layered double hydroxides, is discussed in context of the cellular uptake mecha-nism in cell culture lines and pharmacokinetic and tissue distribution studies in whole animals. In addition, research results on the biodistribution patterns of only fluorescently labeled layered double hydroxides and the subsequent histopathological analysis are described in detail to assess the biocompatibility of layered double hydroxides in vivo. The determination of rela-tionships between delivery efficiency and toxicity can be useful for the rational development of layered double hydroxides as drug delivery systems.
©2009 The Ceramic Society of Japan Journal of the Ceramic Society of Japan. 01/2009; 1175:543-549.
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ABSTRACT: Layered double hydroxides (LDHs) are biocompatible materials which can be used as drug-delivery nanovehicles. In order to define the optimum size of LDH nanoparticles for efficient cellular uptake and drug-delivery pathway, we prepared different sized LDH nanoparticles with narrow size distribution by modulating the crystal growth rate, and labelled each LDH particle with a fluorophore using a silane coupling reaction. The cellular uptake rate of LDHs was found to be highly dependent on particle size (50 > 200 > or = 100 > 350 nm), whose range of 50 to 200 nm was selectively internalized into cells through clathrin-mediated endocytosis with enhanced permeability and retention. Our study clearly shows that not only the particle size plays an important role in the endocytic pathway and processing, but also the size control of LDH nanoparticles results in their targeted uptake to site-specific clathrin-mediated endocytosis. This result provides a new perspective for the design of LDH nanoparticles with maximum ability towards targeted drug delivery.
Chemistry - An Asian Journal 12/2008; 4(1):67-73. · 4.50 Impact Factor
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ABSTRACT: We have successfully intercalated gadolinium (III) diethylenetriamine pentaacetic acid (Gd-DTPA) into layered double hydroxide (LDH). X-ray diffractometry, Infrared spectroscopy, and electron microscopic studies together with T1-weighed contrast image analyses revealed the possiblity of Gd-DTPA/LDH as in vivo magnetic resonance (MR) contrast nanoparticles.
Journal of Nanoscience and Nanotechnology 11/2008; 8(10):5181-4. · 1.56 Impact Factor
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ABSTRACT: Core-shell nanohybrid, Fe3O4@PPY, which consists of superparamagnetic Fe3O4 core and DNA attractive polypyrrole, was successfully synthesized through the free radical polymerization. The DNA retrieval efficacy of the nanohybrid was found to be very high in DNA solution with low concentration (approximately 33% uptake in 100 microM).
Journal of Nanoscience and Nanotechnology 11/2008; 8(10):5014-7. · 1.56 Impact Factor
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ABSTRACT: 4-hydroxy-3-methoxybenzoic acid (vanillic acid: VA), which is a widely used flavoring agent in foods, was successfully intercalated into layered double hydroxide (LDH) to produce VA-LDH nanohybrids. The structure and VA release kinetics of the nanohybrids were systematically investigated with respect to charge density of host LDHs.
Journal of Nanoscience and Nanotechnology 11/2008; 8(10):5018-21. · 1.56 Impact Factor
