Surface-modified poly(lactide-··-glycolide) nanospheres for targeted bone imaging with enhanced labeling and delivery of radioisotope

Park, Yoon Jeong,Nah, Sook Hee,Lee, Jue Yeon,Jeong, Jae Min,Chung, Jun Key,Lee, Myung Chul,Yang, Victor C.,Lee, Seung Jin 梨花女子大學校 藥學硏究所 2003 藥學硏究論文集 Vol.- No.12

Surface-modified nanospheres can be utilized for targeting drugs and diagnostic agents to the bone and bone marrow while extending their circulation time in the blood stream. The surface modification of poly(lactide-co-glvcolide)(PLGA) nanospheres by radioisotope carrying poly(ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) triblock copolymers (Poloxamer 407) has been assessed by in vitro characterization and in vim biodistribution studies after intravenous administration of the nanospheres to the mouse. A hydroxyphenylpropionic acid, a ligand for ^(125)I and ^(131)I labeling, was conjugated to the hydroxyl group of the Poloxamer 407 by using dicyclohexyl carbodiimide. The ligand-conjugated Poloxamer 407 was adsorbed onto the surface of PLGA nanospheres. Surface coating was confirmed by measuring both size distribution and the surface charge of the nanospheres. Besides, ^(125)I-labeling efficiency, radiolabeling stability, whole body imaging, and biodistribution of the radioisotope-labeled nanosphercs were examined. Ligand-labeled, surface-modified PLCA nanospheres were in 100-nm size ranges, which may be adequate for long-circulation and further bone imaging. ^(125)I-labeling efficiency was >90% and was more stable at human serum for 24 h. A noticeable decrease in liver or spleen uptake was obtained by the surface-modified nanospheres, ^(125)I-labeled nanospheres showed higher blood maintenance and bone uptake compared with stannous colloid with the same size distribution. Therefore, a fully biodegradable, radioisotope-carrying, surface-modified nanosphere system has been developed as a promising tool for targeting bone and bone marrows.

Synthesis of highly-energetic nanoparticles based on monodisperse hollow mesoporous nanospheres

Kim, Myoeuem,Lim, Hyun Jun,Kwon, Seho,Lee, Minkee,Jeong, Tae-Yang,Kwon, Yong Ku Elsevier 2019 Microporous and mesoporous materials Vol.277 No.-

<P><B>Abstract</B></P> <P>Highly-energetic monodisperse nanospheres were prepared based on surface-modified, hollow mesoporous silica nanospheres. The monodisperse, cationic polymer nanospheres were prepared by the emulsifier-free emulsion copolymerization and used as a template to obtain copolymer/silica core-shell nanospheres and monodisperse, hollow mesoporous silica (HMS) nanospheres. The surface of the HMS nanospheres was treated with (3-aminopropyl) trimethoxysilane to obtain (3-aminopropyl)trimethoxysilane-grafted HMS nanospheres, which facilitated the adsorption of cyclomethylene trinitramine within the inorganic framework. The uptake of RDX within the dried, final nanospheres was measured by thermogravimetric analysis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel energetic nanoparticles with high surface area were prepared. </LI> <LI> A large quantity of RDX was immobilized within the inorganic framework. </LI> <LI> The nanoscale dispersion of energetic compounds was successfully obtained. </LI> <LI> A large amount of energy and minimum mass transport was achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Crosslinked Polyphosphazene Nanospheres with Anticancer Quercetin: Synthesis, Spectroscopic, Thermal Properties, and Controlled Drug Release

Simge Metinoğlu Örüm,Yasemin Süzen Demircioğlu 한국고분자학회 2018 Macromolecular Research Vol.26 No.8

In this study, novel cross-linked inorganic-organic hybrid polyphosphazene nanospheres were synthesized via self-assembly precipitation polymerization between hexachlorocyclotriphosphazene (HCCP) as a crosslinker molecule and anticancer featured quercetin (QCT). The technique used for synthesizing QCT nanospheres is quite simple and rapid, and has some advantages like using just ultrasonic power. Furthermore, it does not require any surfactant or stabilizer. Growth of nanospheres and reaction time effect on the formation of QCT nanospheres were investigated. Quercetin and 4',7-dihydroxyflavone were compared for the formation of nanospheres. The particle size of the spheres was determined to be approximately 434 nm by DLS (dynamic light scattering) measurements in 3 hours reaction time. The structure and morphology of synthesized QCT nanospheres were investigated by SEMEDX (scanning electron microscope) and XRD (X-ray diffractometer). The spectroscopic and thermal properties of cyclomatrix polyphosphazene QCT nanospheres were investigated by FTIR (Fourier transform infrared spectroscopy), UV-vis (ultravioletvisible), fluorescence, and TGA (thermogravimetric analysis). Moreover, QCT nanospheres were used for controlled release of acriflavine which had been chosen as a model drug.

Facile Synthesis of Fluorine-Doped Hollow Mesoporous Carbon Nanospheres for Supercapacitor Application

이민기,반유정,이주호,이하영,이영동,권용구 한국고분자학회 2020 Macromolecular Research Vol.28 No.13

Hollow mesoporous carbon nanospheres doped with fluorine (FHMC) were synthesized for high-performance supercapacitor applications. Monodisperse nanospheres with a copolymeric core-silica shell were produced by charge density matching. The copolymeric chains in the core phase were crosslinked through a Friedel-Crafts reaction, followed by carbonization at 800 oC under a N2 atmosphere to obtain the core-shell (CSC) nanospheres with a carbon core and silica/carbon composite shell. The silica phase of these core-shell nanospheres was etched selectively during the thermal decomposition of Teflon to synthesize the FHMC nanospheres. During the etching process of silica in the shell phase, the surfaces of the nanospheres were doped with fluorine. The BET surface area was increased significantly from 788 m2/g and 1.31 cm3/g for the CSC nanospheres to 1021 m2/g and 2.55 cm3/g for the FHMC nanospheres. The specific capacitance of the FHMC nanospheres prepared was approximately 174 F/g at a current density of 0.5 A/g. The capacity retention after 10000 charge/discharge cycles at a current density of 1 A/g was approximately 93.6%.

Cholesterol removal onto the different hydrophobic nanospheres: A comparison study

Tulden Kalburcu,Nevra Ozturk,Nalan Tuzmen,Adil Denizli,Sinan Akgo¨ l 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.1

The aim of this study is to prepare two different hydrophobic polymeric nanospheres for cholesterolremoval. Poly(HEMA–MAT) nanospheres with an average size of 100 nm and poly(HEMA–MAP)nanospheres with an average size of 158 nm were produced by surfactant free emulsion polymerizationof HEMA and MAT and MAP monomers. These hydrophobic nanospheres were characterized by FTIR,SEM, elemental analysis, particle size and surface area measurements. Cholesterol removal experimentswere performed in a batch experimental set-up and removal medium was methanol. Cholesteroladsorption capacity of poly(HEMA–MAP) nanospheres was approximately three times higher than thatof poly(HEMA–MAT) nanospheres.

Solvothermal Synthesis of InOOH Nanospheres with Enhanced Photocatalytic Activity

Shuang Yang,Cheng-Yan Xu,Sheng-Peng Hu,Wen-Shou Wang,Jing Yu,Liang Zhen 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.4

Monodispersive indium oxyhydroxide (InOOH) nanospheres were successfully synthesized by an acetic acid-assisted solvothermal method. The structure and morphology of InOOH nanospheres were characterized by means of X-ray diffraction, scanning electron microscope, and transmission electron microscope. The obtained InOOH nanospheres have a porous structure with diameters of 400–650 nm and a relative large specific surface area of 60.63 m2/g. Introducing a trace amount of acetic acid into the reaction system can effectively adjust the reaction rate, realizing the morphology and phase tuning of InOOH nanospheres. The InOOH nanospheres exhibit excellent photocatalytic degradation of Rhodamine B under UV light irradiation, which is ascribed to the porous structures and high-Brunauer–Emmett–Teller surface area of InOOH nanospheres.

Hydrothermal synthesis of wurtzite Zn_1-xNi_xS mesoporous nanospheres: With blue-green emissions and ferromagnetic Curie point above room temperature

Amaranatha Reddy, D.,Kim, D.H.,Rhee, S.J.,Jung, C.U.,Lee, B.W.,Liu, C. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.588 No.-

Wurtzite Zn<SUB>1-x</SUB>Ni<SUB>x</SUB>S (x=0.00, 0.01, 0.02, 0.03, 0.04 and 0.05) mesoporous nanospheres were successfully synthesized via a versatile hydrothermal method with the assistance of ethylenediamine (EN). The as synthesized nanospheres were uniform, mono-dispersed with a spherical shape. Microstructure investigations revealed that these nanospheres were mesoporous clusters of Zn<SUB>1-x</SUB>Ni<SUB>x</SUB>S nanoparticles with the size around 5nm. X-ray Diffraction, X-ray photoelectron spectroscopy, and Energy-dispersive X-ray spectroscopy studies confirmed that the Ni ions substituted into ZnS host lattice without altering the crystal structure. The Fourier-transform infrared spectra confirmed the coupling between the EN molecules and ZnS. The absorption edge in the diffuse reflection spectra shifted towards lower wavelength with increasing Ni concentration, indicating an expansion in the band gap energy that is estimated to be in the range of 3.53-3.60eV. The photoluminescence spectra of the doped and un-doped samples contained a broad emission band covering the range of 350-650nm. Room temperature magnetization studies indicated that the undoped ZnS nanospheres yielded only diamagnetism, whereas the doped samples exhibited ferromagnetism that can be attributed to the Ni<SUP>2+</SUP> dopants. The temperature dependence of magnetization revealed that the Zn<SUB>1-x</SUB>Ni<SUB>x</SUB>S nanospheres have Curie point above room temperature. The intrinsic ferromagnetism and ferromagnetic Curie point above room temperature promise a great deal of potential applications in spintronic devices for Zn<SUB>1-x</SUB>Ni<SUB>x</SUB>S nanospheres.

Close-Packed Colloidal Monolayers of Ultra-Smooth Gold Nanospheres by Controlled Trapping onto Polymer Thin Films

Kim, Jun-Min,Jung, Dae-Woong,Lee, Gaehang,Yi, Gi-Ra The Polymer Society of Korea 2018 Macromolecular Research Vol.26 No.6

Ultra-smooth and highly-spherical gold nanoparticles can form uniform colloidal film from evaporating sessile droplets on substrates at relatively high temperature, in which gold nanospheres are assembled at the air-liquid interface due to fast evaporation and further form multilayers on polystyrene-coated silicon wafer. Then, gold nanospheres at bottom layer are wetted by polystyrene upon thermal annealing around <TEX>$80^{\circ}C$</TEX> and securely trapped in polymer solid film during cooling step. Finally, additionally stacked nanospheres in multilayer film are washed out by simple sonication leaving high-quality colloidal monolayers of gold nanospheres.

Synthesis of NiCo2S4 nanospheres/reduced graphene oxide composite as electrode material for supercapacitor

Weijun Peng,Huilan Chen,Wei Wang,Yanfang Huang,Guihong Han 한국물리학회 2020 Current Applied Physics Vol.20 No.2

The NiCo2S4 nanospheres arrayed on the surface of reduced graphene oxide (rGO) was fabricated via one-step hydrothermal method. The effect of initial feeding mass of Ni(NO3)2·6H2O and Co(NO3)2·6H2O to rGO on the microstructure and electrochemical performance of the as-prepared composites was studied. The results indicated that the specific capacitances of the composites were first increased and then reduced due to the aggregation of NiCo2S4 nanospheres. NiCo2S4 nanospheres/rGO composites exhibited a remarkable specific capacitance of 1406 F/g and excellent cyclic stability of 82.36% at the current density of 1 A/g, which were better than those of individual NiCo2S4 (792 F/g and 64.77%) counterpart. These results showed that the as-prepared NiCo2S4 nanospheres/rGO composites were outstanding candidate for electrode material of supercapacitors

ON THE FORMATION OF TITANIUM/TITANIUM OXIDE NANOFIBROUS STRUCTURES AND NANOSPHERES USING FEMTOSECOND LASER IN AIR

M. ALUBAIDY,K. VENKATAKRISHNAN,B. TAN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.2

In this paper, we report a unique growth of nanofibrous structures and nanospheres of titanium using femtosecond laser in air and without the need for any type of catalyst. The femtosecond laser was used to generate nanoparts on a titanium substrate. The irradiated substrate is assumed to be subjected to plane stress type of temperature variation and a new method combining finite difference and Runge–Kutta 4 transient thermal model has been developed to calculate the temperature distribution on the top surface of the substrate during laser ablation. A Matlab code has been developed and validated with the known results from the literature. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffractograms (XRD) and micro-Raman analysis were conducted to characterize the microstructure and revealed metallic and oxide phases in the nanostructure analyses. Results showed that nanofibers and nanospheres were grown in the order of few hundreds nanometers or more. The effect of the laser power on the energy/pulse and hence the temperature was studied. It was found that high temperature results in the formation of nanofibers while lower temperature results in formation of nanospheres. This first time observation could have potential application in biomedical, optoelectronics and photocatalysis.