Highly dispersed perovskite NdCoO3 nanoparticles were prepared by a novel salt-assisted combustion process. The effects of NaCl content and calcination temperature on the characteristics of the products were character...Highly dispersed perovskite NdCoO3 nanoparticles were prepared by a novel salt-assisted combustion process. The effects of NaCl content and calcination temperature on the characteristics of the products were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and BET surface area measurement. The facile introduction of NaCl in the conventional combustion synthesis process was found to result in the formation of well-dispersed perovskite nanoparticles and increase specific surface areas of the resultants from 1.7 to 43.2 m2·g-1. The catalytic properties of the typical NdCoO3 samples for thermal decomposition of ammonia perchlorate (AP) and their correlation with the NdCoO3 microstructure were investigated by Differential Scanning Calorimetry (DSC). The DSC results indicate that the addition of the amorphous NdCoO3 nanoparticles to AP incorporates two small exothermic peaks of AP into a strong exothermic peak, decreases the temperature of the AP exothermic peak to 314.0 ℃ by reduction of 138.3 ℃ and increases the apparent decomposition heat from 515 J·g-1 to over 1441 J·g-1, showing the intense catalytic activity for thermal decomposition of AP. It is also clear that the catalytic activity of the resultant NdCoO3 is related to their microstructure. According to Kissinger′s method, the kinetics parameters of the thermal decomposition of AP catalyzed by the as-prepared NdCoO3 samples were calculated to account for the order of their catalytic activity.展开更多
Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuousl...Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuously pursued.Unlike normal PSCs fabricated on rigid substrates,producing high-efficiency UF-PSCs remains a challenge due to the difficulty in achieving full coverage and minimizing defects of metal halide perovskite(MHP)films.In this study,we utilized Al_(2)O_(3) nanoparticles(NPs)as an inorganic surface modifier to enhance the wettability and reduce the roughness of poly-bis(4-phenyl)(2,4,6-trimethylphenyl)amine simultaneously.This approach proves essentials in fabricating UF-PSCs,enabling the deposition of uniform and dense MHP films with full coverage and fewer defects.We systematically investigated the effect of Al_(2)O_(3) NPs on film formation,combining simulation with experiments.Our strategy not only significantly increases the power conversion efficiency(PCE)from 11.96%to 16.33%,but also promotes reproducibility by effectively addressing the short circuit issue commonly encountered in UF-PSCs.Additionally,our UF-PSCs demonstrates good mechanical stability,maintaining 98.6%and 79.0%of their initial PCEs after 10,000 bending cycles with radii of 1.0 and 0.5 mm,respectively.展开更多
The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions f...The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions for preparing well-dispersed nanoparticles were found as follows: 0.4 mol/L NaBH4 was added into solution containing 0.2 mol/L Cu2+, 1.0% gelatin dispersant in mass fraction, and 1.2 mol/L NH3?H2O at pH 12 and 313 K. In addition, a series of experiments were performed to discover the reaction process. NH3?H2O was found to be able to modulate the reaction process. At pH=10, Cu2+ was transformed to Cu(NH3)42+ as precursor after the addition of NH3?H2O, and then Cu(NH3)42+ was reduced by NaBH4 solution. At pH=12, Cu2+ was transformed to Cu(OH)2 as precursor after the addition of NH3?H2O, and Cu(OH)2 was then reduced by NaBH4 solution.展开更多
Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid （FA） ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 n...Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid （FA） ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 nanoparticles were characterized by X-ray diffraction diffractometer, transmission electron microscope, FT-IR spectrometer, vibrating sample magnetometer, and dynamic light scattering instrument. The in vivo labeling effect of folate-conjugated Fe3O4 nanoparticles on the hepatoma cells was investigated in tumor-bearing rat. The results demonstrate that the as-prepared nanoparticles have cubic structure of Fe3O4 with a particle size of about 8 nm and hydrated diameter of 25.7 nm at a saturation magnetization of 51 A·m2/kg. These nanoparticles possess good physiological stability, low cytotoxicity on human skin fibroblasts and negligible effect on Wistar rats at the concentration as high as 3 mg/kg body mass. The folate-conjugated Fe3O4 nanoparticles could be effectively mediated into the human hepatoma Bel 7402 cells through the binding of folate and folic acid receptor, enhancing the signal contrast of tumor tissue and surrounding normal tissue in MRI imaging. It is in favor of the tumor cells labeling, tracing, magnetic resonance imaging （MRI） target detection and magnetic hyperthermia.展开更多
Y2O3： Er^3＋, Yb^3＋ nanoparticles were synthesized by a homogeneous precipitation method without and with different concentrations of EDTA 2Na. Upconversion luminescence spectra of the samples were studied under 980...Y2O3： Er^3＋, Yb^3＋ nanoparticles were synthesized by a homogeneous precipitation method without and with different concentrations of EDTA 2Na. Upconversion luminescence spectra of the samples were studied under 980 nm laser excitation. The results of XRD showed that the obtained Y2O3：Er^3＋,Yb^3＋ nanoparticles were of a cubic structure. The average crystallite sizes calculated were in the range of 28-40 nm. Green and red upconversion emission were observed, and attributed to ^2H11/2,^4S3/2→^4I15/2 and ^4F9/2→^4I15/2 transitions of the ion, respectively. The ratio of the intensity of green emission to that of red emission drastically changed with a change in the EDTA 2Na concentration. In the sample synthesized without EDTA, the relative intensity of the green emission was weaker than that of the red emission. The relative intensities of green emission increased with the increased amount of EDTA 2Na used. The possible upconversion luminescence mechanisms were discussed.展开更多
Glypican-3 （GPC3） is reported as a great promising tumor marker for hepatocellular carcinoma （HCC） diagnosis. Highly sensitive and accurate analysis of serum GPC3 （sGPC3）, in combination with or instead of tradi...Glypican-3 （GPC3） is reported as a great promising tumor marker for hepatocellular carcinoma （HCC） diagnosis. Highly sensitive and accurate analysis of serum GPC3 （sGPC3）, in combination with or instead of traditional HCC marker alpha-fetoprotein （AFP）, is essential for early diagnosis of I-ICC. Biomaterial-functionalized magnetic particles have been utilized as solid supports with good biological compatibility for sensitive immunoassay. Here, the magnetic nanoparticles （MnPs） and magnetic microparticles （MmPs） with carboxyl groups were further modified with streptavidin, and applied for the development of chemiluminescence enzyme immunoassay （CLEIA）. After comparing between MnPs- and MmPs-based CLEIA, MnPs-based CLEIA was proved to be a better method with less assay time, greater sensitivity, better linearity and longer chemiluminescence platform. MnPs-based CLEIA was applied for detection of sGPC3 in normal liver, hepatocirrhosis, secondary liver cancer and HCC serum samples. The results indicated that sGPC3 was effective in diagnosis of HCC with high performance.展开更多
The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM）, UV-vis diffuse ...The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM）, UV-vis diffuse reflectance spectrum, and photoluminescence spectra.The results of XRD indicated that the obtained LaF3：Eu^3＋ nanoparticles were well crystallized with a hexagonal structure.The FE-SEM image illustrated that the LaF3：Eu^3＋ nanoparticles were spherical with an average size around 30 nm.Under irradiation of UV light, the emission spectrum of LaF3：Eu^3＋ nanoparticles exhibited the characteristic line emissions arising from the 5D0→7FJ（J=1, 2, 3, 4） transitions of the Eu3＋ ions, with the dominating emission centered at 590 nm.In addition, the emissions from the 5D1 level could be clearly observed due to the low phonon energies（-350 cm^-1） of LaF3 matrix.The optimum doping concentration for LaF3：Eu3＋ nanoparticles was determined to be 20mol.%.展开更多
Schwann ceils and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this stud...Schwann ceils and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this study, we have transfected neurotrophin-3 into Schwann cells cultured in vitro using nanoparticle liposomes. Results showed that neurotrophin-3 was successfully transfected into Schwann cells, where it was expressed effectively and steadily. A composite of Schwann cells transfected with neurotrophin-3 and poly（lactic-co-glycolic acid） biodegradable conduits was transplanted into rats to repair 10-mm sciatic nerve defects. Transplantation of the composite scaffold could restore the myoelectricity and wave amplitude of the sciatic nerve by electrophysiological examination, promote nerve axonal and myelin regeneration, and delay apoptosis of spinal motor neurons. Experimental findings indicate that neurotrophin-3 transfected Schwann cells combined with bridge grafting can promote neural regeneration and functional recovery after nerve injury.展开更多
Peroxidase-like catalytic properties of Fe3O4 nanoparficles （NPs） with three different sizes, synthesized by chemical coprecipitation and sol-gel methods, were investigated by UV-vis spectrum analysis. By comparing ...Peroxidase-like catalytic properties of Fe3O4 nanoparficles （NPs） with three different sizes, synthesized by chemical coprecipitation and sol-gel methods, were investigated by UV-vis spectrum analysis. By comparing Fe3O4 NPs with average diameters of 11, 20, and 150 nm, we found that the catalytic activity increases with the reduced nanoparticle size. The electrochemical method to characterize the catalytic activity of Fe3O4 NPs using the response currents of the reaction product and substrate was also developed.展开更多
AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divid...AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divided into group A receiving normal saline, group B receiving magnetic nanoparticles containing 5-fluorouracil (5-FU), group C receiving 5-FU, and group D receiving magnetic nanoparticles containing 5-FU with a magnetic field built in tumor tissues. The tumor volume was measured on the day before treatment and 1, 4, 7, 10 and 13 d after treatment. Tumor tissues were isolated for examination of the expression of bcl-2, bax and caspase 3 by immunohistochemical method, reverse transcription polymerase chain reaction and Western blotting. RESULTS: The tumor volume was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01). The volume was markedly lower in group D than in group C (P < 0.05). The expression of protein and mRNA of bcl-2 was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01), and was markedly lower in group D than in group C (P < 0.01). The expression of bax and caspase 3 in groups C and D was signif icantly increased, compared with that in groups A and B (P < 0.01). CONCLUSION: The targeted magnetic nanoparticles containing 5-FU can improve the chemotherapeutic effect of 5-FU against hepatocellular carcinoma by decreasing the expression of bcl-2 gene, and increasing the expression of bax and caspase 3 genes.展开更多
An in situ reduction method has been developed to fabricate metallic Ag nanoparticles inside the channels of mesoporous carbon CMK-3. This approach combines function of the CMK-3 surface by oxidation using HNO3 with t...An in situ reduction method has been developed to fabricate metallic Ag nanoparticles inside the channels of mesoporous carbon CMK-3. This approach combines function of the CMK-3 surface by oxidation using HNO3 with the subsequent absorption of Ag^＋ The resultant nanocomposite materials were characterized by nitrogen adsorption, X-ray diffraction, Auger electron spectroscopy and transmission electron microscopy. Compared with the conventional impregnation method, our approach shows that Ag nanonarticles of 2-4 nm can be uniformlv incorporated into CMK-3.展开更多
Fe3O4 nanoparticles were prepared by chemistry co-precipitation and the mean crystal size was 17.9 nm measured by XRD. After it had been treated by silane-coupling agents KH570, magnetic micro-spheres dispersed in org...Fe3O4 nanoparticles were prepared by chemistry co-precipitation and the mean crystal size was 17.9 nm measured by XRD. After it had been treated by silane-coupling agents KH570, magnetic micro-spheres dispersed in organic medium glycol were gained and the mean size of Fe3O4 nanopowders was 33.7 nm. So it can be concluded that magnetic micro-sphere is made of a few Fe3O4 crystals. Many factors of modification were researched, such as the time of ball milling, the content of Fe3O4 and the content of KH570. The modification of Fe3O4 is relative to the time of ball milling, but the dominant function is affected by the content of Fe3O4 and KH570. When the content of Fe3O4 is known, there is a suitable content of KH570. Different content of Fe3O4 will make the different suitable content of KH570, but the range of latter is less than former, which is relative to the distribution of KH570 on Fe3O4 surface or in the solution.展开更多
In this study, poly（y-glutamic acid）-coated Fe3O4 magnetic nanoparticles （y-PGA/Fe304 MNPs） were successfully fabricated using the co-precipitation method. Fe3O4 MNPs were also prepared for comparison. The av erag...In this study, poly（y-glutamic acid）-coated Fe3O4 magnetic nanoparticles （y-PGA/Fe304 MNPs） were successfully fabricated using the co-precipitation method. Fe3O4 MNPs were also prepared for comparison. The av erage size and specific surface area results reveal that 7-PGA/Fe304 MNPs （52.4 nm, 88.41 m2.g-1） have smaller particle size and larger specific surface area_ than Fe3O4 MNPs （62.0 nm, 76.83 mLg-1）. The y-PGA/Fe3O4 MNPs展开更多
Polyacrylonitrile（PAN）/Fe3O4 composite nanofibers were successfully obtained through electrospinning and sol-gel technology. The resulting magnetic Fe3O4 nanoparticles were homogeneously distributed on the surface o...Polyacrylonitrile（PAN）/Fe3O4 composite nanofibers were successfully obtained through electrospinning and sol-gel technology. The resulting magnetic Fe3O4 nanoparticles were homogeneously distributed on the surface of PAN nanofibers and the diameters of polyacrylonitrile nanofibers and nanoparticles were easily controlled, respectively. The distribution of Fe3O4 nanoparticles inside the nanofibrous composite was investigated by field emission scanning electron microscopy and transmission electron microscopy. X-ray diffraction reveals the presence of Fe3O4 nanoparticles in the composite nanofiber. The resulting sample shows a super paramagnetic behavior.展开更多
A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Cop...A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.展开更多
Objective:To investigate the inhibitory effect of humanized anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles conjugate on growth of human hepatocellular carcinoma both in vitro and in vivo,which may be a potential agents...Objective:To investigate the inhibitory effect of humanized anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles conjugate on growth of human hepatocellular carcinoma both in vitro and in vivo,which may be a potential agents with sensitivity and targeting ability for human hepatocellular cancer.Methods:Humanized anli-VECFR-2 ScFv-As2O3-stealth nanoparticles conjugate was previously constructed using ribosome display technology and antibody conjugate technology.In this combined in vitro and in vivo study,the inhibitory effects of anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles conjugate on tumor growth,invasion,and metastasis was observed with human liver carcinoma cell line Bel7402 and normal cell L02 by MTT assay,Tanswell assay,Hochest33258 staining,and DNA ladder analysis.The anticancer activity and distribution of anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles was then verified in a mouse model of Bel7402xenografts.Results:Anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles significantly inhibited the proliferation of Bel7402 in the 3-(4,5-dimethylthiazol-2-yh-2,5-diphenyltetrazolium bromide assay while had almost no effects on L02 cells.And the apoptosis inducing effects were proved by Hochest33258 staining and DNA ladder analysis.Transwell assay found that the drug also inhibited the metastasis ability of tumor cells.Furthermore,anti-VEGFR-2 ScFv-As^-stealth nanoparticles significantly delayed the growth of Bel7402 xenografts after administration（92.9%）,followed by As2O3-stealth nanoparticles,anti-VEGFR-2 ScFv,and As203（61.4%,58.8%,20.5%,P【0.05）.The concentration of As2O3 in anti-VEGFR-2 ScFv-As2O3-steallh nanoparticles group was more selectively.Conclusions:Anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles is a potent and selective anti-hepatocellular carcinoma agent which could inhibit the growth of liver cancer as a targeting agent both in vitro and in vivo and also significantly inhibit angiogenesis.展开更多
Inhibiting the “shuttle effect” of soluble polysulfides and improving reaction kinetics are the key factors necessary for further exploration of high-performance Li-S batteries. Herein, an effective interface engine...Inhibiting the “shuttle effect” of soluble polysulfides and improving reaction kinetics are the key factors necessary for further exploration of high-performance Li-S batteries. Herein, an effective interface engineering strategy is reported, wherein nitriding of an Ni-based precursor is controlled to enhance Li-S cell regulation. The resulting in-situ formed NiO-Ni_(3)N heterostructure interface not only has a stronger polysulfide adsorption effect than that of monomeric NiO or Ni_(3)N but also has a faster Li ion diffusion ability than a simple physical mixture. More importantly, this approach couples the respective advantages of NiO and Ni_(3)N to reduce polarization and facilitate electron transfer during polysulfide reactions and synergistically catalyze polysulfide conversion. In addition, ultrafine nanoparticles are thought to effectively improve the use of additive materials. In summary, Li-S batteries based on this NiO-Ni_(3)N heterostructure have the features of long cycle stability, rapid charging-discharging, and good performance under high sulfur loading.展开更多
The surface organic modification of Fe3O4 nanoparticles with silane coupling reagent KH570 was studied. The modified and unmodified nanoparticles were characterized by FT-IR, XPS and TEM. The spectra of FT-IR and XPS ...The surface organic modification of Fe3O4 nanoparticles with silane coupling reagent KH570 was studied. The modified and unmodified nanoparticles were characterized by FT-IR, XPS and TEM. The spectra of FT-IR and XPS revealed that KH570 was coated onto the surface of Fe3O4 nanoparticles to get Fe-O- Si bond and an organic coating layer also was formed. Fe3O4 nanoparticles were spheres partly with mean size of 18,8 nm studied by TEM, which was consistent with the result 17.9 nm calculated by Scherrer＇s equation. KH570 was adsorbed on surface and formed chemistry bond to be steric hindrance repulsion which prevented nanoparticles from reuniting. Then glycol-based Fe3O4 magnetic liquids dispersed stably was gained.展开更多
基金the National Natural Science Foundation of China (50306008)Start up Research Fund of Nanchang University and the Natural Science Foundation of Higher Education Institutions in Anhui Province (KJ2007B231)
文摘Highly dispersed perovskite NdCoO3 nanoparticles were prepared by a novel salt-assisted combustion process. The effects of NaCl content and calcination temperature on the characteristics of the products were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and BET surface area measurement. The facile introduction of NaCl in the conventional combustion synthesis process was found to result in the formation of well-dispersed perovskite nanoparticles and increase specific surface areas of the resultants from 1.7 to 43.2 m2·g-1. The catalytic properties of the typical NdCoO3 samples for thermal decomposition of ammonia perchlorate (AP) and their correlation with the NdCoO3 microstructure were investigated by Differential Scanning Calorimetry (DSC). The DSC results indicate that the addition of the amorphous NdCoO3 nanoparticles to AP incorporates two small exothermic peaks of AP into a strong exothermic peak, decreases the temperature of the AP exothermic peak to 314.0 ℃ by reduction of 138.3 ℃ and increases the apparent decomposition heat from 515 J·g-1 to over 1441 J·g-1, showing the intense catalytic activity for thermal decomposition of AP. It is also clear that the catalytic activity of the resultant NdCoO3 is related to their microstructure. According to Kissinger′s method, the kinetics parameters of the thermal decomposition of AP catalyzed by the as-prepared NdCoO3 samples were calculated to account for the order of their catalytic activity.
基金supported by the National Natural Science Foundation of China(22005043,52272193)the National Key Research and Development Program of China(2019YFA0709102 and 2020YFA0714502)+1 种基金the Liaoning Revitalization Talents Program(XLYC2007038,XLYC2008032)the Fundamental Research Funds for the Central Universities(DUT22LAB602,DUT22GJ201).
文摘Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuously pursued.Unlike normal PSCs fabricated on rigid substrates,producing high-efficiency UF-PSCs remains a challenge due to the difficulty in achieving full coverage and minimizing defects of metal halide perovskite(MHP)films.In this study,we utilized Al_(2)O_(3) nanoparticles(NPs)as an inorganic surface modifier to enhance the wettability and reduce the roughness of poly-bis(4-phenyl)(2,4,6-trimethylphenyl)amine simultaneously.This approach proves essentials in fabricating UF-PSCs,enabling the deposition of uniform and dense MHP films with full coverage and fewer defects.We systematically investigated the effect of Al_(2)O_(3) NPs on film formation,combining simulation with experiments.Our strategy not only significantly increases the power conversion efficiency(PCE)from 11.96%to 16.33%,but also promotes reproducibility by effectively addressing the short circuit issue commonly encountered in UF-PSCs.Additionally,our UF-PSCs demonstrates good mechanical stability,maintaining 98.6%and 79.0%of their initial PCEs after 10,000 bending cycles with radii of 1.0 and 0.5 mm,respectively.
文摘The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions for preparing well-dispersed nanoparticles were found as follows: 0.4 mol/L NaBH4 was added into solution containing 0.2 mol/L Cu2+, 1.0% gelatin dispersant in mass fraction, and 1.2 mol/L NH3?H2O at pH 12 and 313 K. In addition, a series of experiments were performed to discover the reaction process. NH3?H2O was found to be able to modulate the reaction process. At pH=10, Cu2+ was transformed to Cu(NH3)42+ as precursor after the addition of NH3?H2O, and then Cu(NH3)42+ was reduced by NaBH4 solution. At pH=12, Cu2+ was transformed to Cu(OH)2 as precursor after the addition of NH3?H2O, and Cu(OH)2 was then reduced by NaBH4 solution.
基金Project(2011JQ028)supported by the Fundamental Research Funds for the Central Universities,ChinaProjects(2008SK3114,2010SK3113)supported by Hunan Provincial Science&Technology Plan,China+2 种基金Project(B2007086)supported by Science&Research Funds of Hunan Health Department,ChinaProject(12JJ5057)supported by Natural Science Foundation of Hunan Province,ChinaProjects(XCX1119,XCX12073)supported by University Students Innovative Experiment Plan Project of Hunan Agricultural University,China
文摘Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid （FA） ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 nanoparticles were characterized by X-ray diffraction diffractometer, transmission electron microscope, FT-IR spectrometer, vibrating sample magnetometer, and dynamic light scattering instrument. The in vivo labeling effect of folate-conjugated Fe3O4 nanoparticles on the hepatoma cells was investigated in tumor-bearing rat. The results demonstrate that the as-prepared nanoparticles have cubic structure of Fe3O4 with a particle size of about 8 nm and hydrated diameter of 25.7 nm at a saturation magnetization of 51 A·m2/kg. These nanoparticles possess good physiological stability, low cytotoxicity on human skin fibroblasts and negligible effect on Wistar rats at the concentration as high as 3 mg/kg body mass. The folate-conjugated Fe3O4 nanoparticles could be effectively mediated into the human hepatoma Bel 7402 cells through the binding of folate and folic acid receptor, enhancing the signal contrast of tumor tissue and surrounding normal tissue in MRI imaging. It is in favor of the tumor cells labeling, tracing, magnetic resonance imaging （MRI） target detection and magnetic hyperthermia.
基金the Foundation for the University by Educational Department of Liaoning (05L337)Key Laboratory of Rare Earth Chemistry and Physics, Chinese Academy of Sciences
文摘Y2O3： Er^3＋, Yb^3＋ nanoparticles were synthesized by a homogeneous precipitation method without and with different concentrations of EDTA 2Na. Upconversion luminescence spectra of the samples were studied under 980 nm laser excitation. The results of XRD showed that the obtained Y2O3：Er^3＋,Yb^3＋ nanoparticles were of a cubic structure. The average crystallite sizes calculated were in the range of 28-40 nm. Green and red upconversion emission were observed, and attributed to ^2H11/2,^4S3/2→^4I15/2 and ^4F9/2→^4I15/2 transitions of the ion, respectively. The ratio of the intensity of green emission to that of red emission drastically changed with a change in the EDTA 2Na concentration. In the sample synthesized without EDTA, the relative intensity of the green emission was weaker than that of the red emission. The relative intensities of green emission increased with the increased amount of EDTA 2Na used. The possible upconversion luminescence mechanisms were discussed.
基金supported by the National Basic Research Program of China (973 Program,No.2007CB714507)the National Natural Science Foundation of China (No.90813015)
文摘Glypican-3 （GPC3） is reported as a great promising tumor marker for hepatocellular carcinoma （HCC） diagnosis. Highly sensitive and accurate analysis of serum GPC3 （sGPC3）, in combination with or instead of traditional HCC marker alpha-fetoprotein （AFP）, is essential for early diagnosis of I-ICC. Biomaterial-functionalized magnetic particles have been utilized as solid supports with good biological compatibility for sensitive immunoassay. Here, the magnetic nanoparticles （MnPs） and magnetic microparticles （MmPs） with carboxyl groups were further modified with streptavidin, and applied for the development of chemiluminescence enzyme immunoassay （CLEIA）. After comparing between MnPs- and MmPs-based CLEIA, MnPs-based CLEIA was proved to be a better method with less assay time, greater sensitivity, better linearity and longer chemiluminescence platform. MnPs-based CLEIA was applied for detection of sGPC3 in normal liver, hepatocirrhosis, secondary liver cancer and HCC serum samples. The results indicated that sGPC3 was effective in diagnosis of HCC with high performance.
基金supported by the Natural Science Foundation of Henan Province (082300440130, 2008A180039, 2007150049)Startup Fund for Doctoral Program of Zhoukou Normal University
文摘The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM）, UV-vis diffuse reflectance spectrum, and photoluminescence spectra.The results of XRD indicated that the obtained LaF3：Eu^3＋ nanoparticles were well crystallized with a hexagonal structure.The FE-SEM image illustrated that the LaF3：Eu^3＋ nanoparticles were spherical with an average size around 30 nm.Under irradiation of UV light, the emission spectrum of LaF3：Eu^3＋ nanoparticles exhibited the characteristic line emissions arising from the 5D0→7FJ（J=1, 2, 3, 4） transitions of the Eu3＋ ions, with the dominating emission centered at 590 nm.In addition, the emissions from the 5D1 level could be clearly observed due to the low phonon energies（-350 cm^-1） of LaF3 matrix.The optimum doping concentration for LaF3：Eu3＋ nanoparticles was determined to be 20mol.%.
基金financially supported by the grants for Science and Technology Innovation Talents in Universities in Ministry of Education of Henan Province in 2010,No.2010HASTIT036
文摘Schwann ceils and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this study, we have transfected neurotrophin-3 into Schwann cells cultured in vitro using nanoparticle liposomes. Results showed that neurotrophin-3 was successfully transfected into Schwann cells, where it was expressed effectively and steadily. A composite of Schwann cells transfected with neurotrophin-3 and poly（lactic-co-glycolic acid） biodegradable conduits was transplanted into rats to repair 10-mm sciatic nerve defects. Transplantation of the composite scaffold could restore the myoelectricity and wave amplitude of the sciatic nerve by electrophysiological examination, promote nerve axonal and myelin regeneration, and delay apoptosis of spinal motor neurons. Experimental findings indicate that neurotrophin-3 transfected Schwann cells combined with bridge grafting can promote neural regeneration and functional recovery after nerve injury.
基金This work was supported by the National Natural Science Foundation of China （Nos. 90406023 and 60571031）；National Important Science Research Program of China （Nos. 2006CB933206 and 2006CB705606）.
文摘Peroxidase-like catalytic properties of Fe3O4 nanoparficles （NPs） with three different sizes, synthesized by chemical coprecipitation and sol-gel methods, were investigated by UV-vis spectrum analysis. By comparing Fe3O4 NPs with average diameters of 11, 20, and 150 nm, we found that the catalytic activity increases with the reduced nanoparticle size. The electrochemical method to characterize the catalytic activity of Fe3O4 NPs using the response currents of the reaction product and substrate was also developed.
基金Supported by the Hi-Tech Research and Development Program of China, NO.2002AA214061
文摘AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divided into group A receiving normal saline, group B receiving magnetic nanoparticles containing 5-fluorouracil (5-FU), group C receiving 5-FU, and group D receiving magnetic nanoparticles containing 5-FU with a magnetic field built in tumor tissues. The tumor volume was measured on the day before treatment and 1, 4, 7, 10 and 13 d after treatment. Tumor tissues were isolated for examination of the expression of bcl-2, bax and caspase 3 by immunohistochemical method, reverse transcription polymerase chain reaction and Western blotting. RESULTS: The tumor volume was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01). The volume was markedly lower in group D than in group C (P < 0.05). The expression of protein and mRNA of bcl-2 was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01), and was markedly lower in group D than in group C (P < 0.01). The expression of bax and caspase 3 in groups C and D was signif icantly increased, compared with that in groups A and B (P < 0.01). CONCLUSION: The targeted magnetic nanoparticles containing 5-FU can improve the chemotherapeutic effect of 5-FU against hepatocellular carcinoma by decreasing the expression of bcl-2 gene, and increasing the expression of bax and caspase 3 genes.
基金the financial support of the National Natural Science Foundation of China(No.20573106)the Ministry of Science and Technology of China through the National Key Project of Fundamental Research.
文摘An in situ reduction method has been developed to fabricate metallic Ag nanoparticles inside the channels of mesoporous carbon CMK-3. This approach combines function of the CMK-3 surface by oxidation using HNO3 with the subsequent absorption of Ag^＋ The resultant nanocomposite materials were characterized by nitrogen adsorption, X-ray diffraction, Auger electron spectroscopy and transmission electron microscopy. Compared with the conventional impregnation method, our approach shows that Ag nanonarticles of 2-4 nm can be uniformlv incorporated into CMK-3.
基金This work was financially supported by the Graduate Innovation Plan Projects of Jiangsu Province in 2005.
文摘Fe3O4 nanoparticles were prepared by chemistry co-precipitation and the mean crystal size was 17.9 nm measured by XRD. After it had been treated by silane-coupling agents KH570, magnetic micro-spheres dispersed in organic medium glycol were gained and the mean size of Fe3O4 nanopowders was 33.7 nm. So it can be concluded that magnetic micro-sphere is made of a few Fe3O4 crystals. Many factors of modification were researched, such as the time of ball milling, the content of Fe3O4 and the content of KH570. The modification of Fe3O4 is relative to the time of ball milling, but the dominant function is affected by the content of Fe3O4 and KH570. When the content of Fe3O4 is known, there is a suitable content of KH570. Different content of Fe3O4 will make the different suitable content of KH570, but the range of latter is less than former, which is relative to the distribution of KH570 on Fe3O4 surface or in the solution.
基金Supported by the National Natural Science Foundation of China （21276124）, the Research Project of Natural Science for Universities Affiliated to Jiangsu Province （10KJB530002）, Key Projects in the National Science ＆ Technology Pillar Pro-gram （2011BAE07B09-3）, the Jiangsu Provincial Science and Technology Support Program （BE2011831）, and the State High Technology Research and Development Prograr of China （2011AA02A201）.
文摘In this study, poly（y-glutamic acid）-coated Fe3O4 magnetic nanoparticles （y-PGA/Fe304 MNPs） were successfully fabricated using the co-precipitation method. Fe3O4 MNPs were also prepared for comparison. The av erage size and specific surface area results reveal that 7-PGA/Fe304 MNPs （52.4 nm, 88.41 m2.g-1） have smaller particle size and larger specific surface area_ than Fe3O4 MNPs （62.0 nm, 76.83 mLg-1）. The y-PGA/Fe3O4 MNPs
基金Supported by the National High Tech Research and Development Programme of China(No.2007AA03Z324)National Basic Research Program of China(No. 228 2007CD936203)National Natural Science Foundation of China(Nos.20674027 and50873045)
文摘Polyacrylonitrile（PAN）/Fe3O4 composite nanofibers were successfully obtained through electrospinning and sol-gel technology. The resulting magnetic Fe3O4 nanoparticles were homogeneously distributed on the surface of PAN nanofibers and the diameters of polyacrylonitrile nanofibers and nanoparticles were easily controlled, respectively. The distribution of Fe3O4 nanoparticles inside the nanofibrous composite was investigated by field emission scanning electron microscopy and transmission electron microscopy. X-ray diffraction reveals the presence of Fe3O4 nanoparticles in the composite nanofiber. The resulting sample shows a super paramagnetic behavior.
文摘A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.
基金supported by Natural Science Foundation of China(81060187)the Natural Science Foundation of Jiangxi Province(2008GQY0050)
文摘Objective:To investigate the inhibitory effect of humanized anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles conjugate on growth of human hepatocellular carcinoma both in vitro and in vivo,which may be a potential agents with sensitivity and targeting ability for human hepatocellular cancer.Methods:Humanized anli-VECFR-2 ScFv-As2O3-stealth nanoparticles conjugate was previously constructed using ribosome display technology and antibody conjugate technology.In this combined in vitro and in vivo study,the inhibitory effects of anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles conjugate on tumor growth,invasion,and metastasis was observed with human liver carcinoma cell line Bel7402 and normal cell L02 by MTT assay,Tanswell assay,Hochest33258 staining,and DNA ladder analysis.The anticancer activity and distribution of anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles was then verified in a mouse model of Bel7402xenografts.Results:Anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles significantly inhibited the proliferation of Bel7402 in the 3-(4,5-dimethylthiazol-2-yh-2,5-diphenyltetrazolium bromide assay while had almost no effects on L02 cells.And the apoptosis inducing effects were proved by Hochest33258 staining and DNA ladder analysis.Transwell assay found that the drug also inhibited the metastasis ability of tumor cells.Furthermore,anti-VEGFR-2 ScFv-As^-stealth nanoparticles significantly delayed the growth of Bel7402 xenografts after administration（92.9%）,followed by As2O3-stealth nanoparticles,anti-VEGFR-2 ScFv,and As203（61.4%,58.8%,20.5%,P【0.05）.The concentration of As2O3 in anti-VEGFR-2 ScFv-As2O3-steallh nanoparticles group was more selectively.Conclusions:Anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles is a potent and selective anti-hepatocellular carcinoma agent which could inhibit the growth of liver cancer as a targeting agent both in vitro and in vivo and also significantly inhibit angiogenesis.
基金financial support of the Youth Project of the Provincial Natural Science Foundation of Anhui(No. 2008085QE267)the Doctoral Research Initiation Foundation of Anhui Normal University (No. 751973)+2 种基金the National Natural Science Foundation of China (No. 51972162)the Fundamental Research Funds for the Central Universities (No. 0213-14380196)the Science and Technology Project of Nanchang (No. 2017-SJSYS-008)。
文摘Inhibiting the “shuttle effect” of soluble polysulfides and improving reaction kinetics are the key factors necessary for further exploration of high-performance Li-S batteries. Herein, an effective interface engineering strategy is reported, wherein nitriding of an Ni-based precursor is controlled to enhance Li-S cell regulation. The resulting in-situ formed NiO-Ni_(3)N heterostructure interface not only has a stronger polysulfide adsorption effect than that of monomeric NiO or Ni_(3)N but also has a faster Li ion diffusion ability than a simple physical mixture. More importantly, this approach couples the respective advantages of NiO and Ni_(3)N to reduce polarization and facilitate electron transfer during polysulfide reactions and synergistically catalyze polysulfide conversion. In addition, ultrafine nanoparticles are thought to effectively improve the use of additive materials. In summary, Li-S batteries based on this NiO-Ni_(3)N heterostructure have the features of long cycle stability, rapid charging-discharging, and good performance under high sulfur loading.
基金the Natural Science Fund of Jiangsu province (No.BK2007586)Jiangsu Planned Projects(No.0701012B)for Postdoctoral Research Funds
文摘The surface organic modification of Fe3O4 nanoparticles with silane coupling reagent KH570 was studied. The modified and unmodified nanoparticles were characterized by FT-IR, XPS and TEM. The spectra of FT-IR and XPS revealed that KH570 was coated onto the surface of Fe3O4 nanoparticles to get Fe-O- Si bond and an organic coating layer also was formed. Fe3O4 nanoparticles were spheres partly with mean size of 18,8 nm studied by TEM, which was consistent with the result 17.9 nm calculated by Scherrer＇s equation. KH570 was adsorbed on surface and formed chemistry bond to be steric hindrance repulsion which prevented nanoparticles from reuniting. Then glycol-based Fe3O4 magnetic liquids dispersed stably was gained.
