A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owi...A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owing to the unique three-dimensional network of c-MnOOH embedded in the porous structure of MWCNTs,the c-MnOOH/MWCNTs composite could have an advantage of high electrocatalytic activities over those of two other kinds of cathode materials(MWCNTs and c-MnOOH/MWCNTs mixture).The results of chargedischarge tests showed that the c-MnOOH/MWCNTs composite as a cathode material of lithium-air batteries could effectively enhance the catalytic activity for the oxygen evolution reduction(OER)process.The lithium-air battery based on c-MnOOH/MWCNTs composite exhibits low charge potential and high discharge capacity.展开更多
A series of nanocomposites based on poly（ε-caprolactone） （PCL） and graphene oxide （GO） were prepared by in situ polymerization. Scanning electron microscopy observation revealed not only a well dispersion of GO...A series of nanocomposites based on poly（ε-caprolactone） （PCL） and graphene oxide （GO） were prepared by in situ polymerization. Scanning electron microscopy observation revealed not only a well dispersion of GO but also a strong interfacial interaction between GO and the PCL matrix, as evidenced by the presence of some GO nanosheets embedded in the matrix. Effects of GO nanofillers on the crystal structure, crystallization behavior and spherulitic morphology of the PCL matrix were investigated in detail. The results showed that the crystallization temperature of PCL enhanced significantly due to the presence of GO in the nanocomposites, however, the addition of GO did not affect the crystal structure greatly. Thermal stability of PCL remarkably increased with the addition of GO nanosheets, compared with that of pure PCL. Incorporation of GO greatly improved the tensile strength and Young＇s modulus of PCL without a significant loss of the elongation at break.展开更多
X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copo...X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications.展开更多
A series of magnetic nanoeomposites based on poly（s-caprolactone） （PCL） and Fe3O4 nanoparticles were prepared using a facile in situ polymerization method. The chemical structures of the PCL/Fe3O4 nanocomposites w...A series of magnetic nanoeomposites based on poly（s-caprolactone） （PCL） and Fe3O4 nanoparticles were prepared using a facile in situ polymerization method. The chemical structures of the PCL/Fe3O4 nanocomposites were characterized by Fourier transform infrared （FTIR） spectroscopy. Results of wide-angle X-ray diffraction （WAXD） showed that the incorporation of the Fe3O4 nanoparticles did not affect the crystallization structure of the PCL. Both scanning electron microscopy （SEM） and transmission electron microscopy （TEM） were used to characterize the morphology and dispersion of the Fe3O4 nanoparticles within the as-synthesized nanocomposites. Results of differential scanning calorimetry （DSC） and polarizing optical microscopy （POM） showed that the crystallization temperature was raised and the spherulites size decreased by the presence of Fe3O4 nanoparticles in the nanocomposites due to the heterogeneous nucleation effect. The thermal stability of the PCL was depressed by incorporation of Fe3O4 nanoparticles from thermogravimetric analysis （TGA）. The superparamagnetic behavior of the PCL/Fe3O4 nanocomposites was testified by the superconducting quantum interference device （SQUID） magnetometer analysis. The obtained biodegradable nanocomposites will have a great potential in magnetic resonance imaging contrast and targeted drug delivery.展开更多
The aim of the current study is to report an inherently radiopaque drug-eluted beads(DEBs)as promising embolic materials for TACE techniques.Firstly,the synthesized radiopaque iodinated polycaprolactonepolyurethanes(I...The aim of the current study is to report an inherently radiopaque drug-eluted beads(DEBs)as promising embolic materials for TACE techniques.Firstly,the synthesized radiopaque iodinated polycaprolactonepolyurethanes(I-PCLUs)are synthesized by chain-extending method by using 4,4-′isopropylidinedi-(2,6-diiodophenol)(IBPA)as the radiopacifying agent.Then,doxorubicin(Dox)is introduced as a chemotherapeutic agent into I-PCLU beads via a double emulsification(W/O/W)method.The drug loading and controlled release behavior of two ratios of I-PCLU/Dox are found to be dependent upon the internal porous microstructure,and the radiopacity is well-retained after four weeks drug release.Besides,the I-PCLU/Dox beads exhibit positive in vitro anti-tumor effect.The in vivo intramuscular implantation and liver embolization results demonstrate that I-PCLU beads have good histocompatibility,occlusion effect and X-ray traceability.Furthermore,the drug-loaded I-PCLU beads are performed into a VX2 rabbit hepatocellular carcinoma(HCC)model using a micro-catheter,form embolization of hepatic arteries and inhibit the tumor growth after one week post-injection.Hence,this polymeric system provides a potential radiopaque chemoembolization candidate for HCC and other cancer therapies,which could bring opportunities to the next generation of multifunctional embolic agents.展开更多
基金supported by the National High Technology Research and Development Program of China(2011AA11A255)
文摘A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owing to the unique three-dimensional network of c-MnOOH embedded in the porous structure of MWCNTs,the c-MnOOH/MWCNTs composite could have an advantage of high electrocatalytic activities over those of two other kinds of cathode materials(MWCNTs and c-MnOOH/MWCNTs mixture).The results of chargedischarge tests showed that the c-MnOOH/MWCNTs composite as a cathode material of lithium-air batteries could effectively enhance the catalytic activity for the oxygen evolution reduction(OER)process.The lithium-air battery based on c-MnOOH/MWCNTs composite exhibits low charge potential and high discharge capacity.
基金financially supported by the National Natural Science Foundation of China(No.31000427)the Fundamental Research Funds for the Central Universities(DUT12JB09)
文摘A series of nanocomposites based on poly（ε-caprolactone） （PCL） and graphene oxide （GO） were prepared by in situ polymerization. Scanning electron microscopy observation revealed not only a well dispersion of GO but also a strong interfacial interaction between GO and the PCL matrix, as evidenced by the presence of some GO nanosheets embedded in the matrix. Effects of GO nanofillers on the crystal structure, crystallization behavior and spherulitic morphology of the PCL matrix were investigated in detail. The results showed that the crystallization temperature of PCL enhanced significantly due to the presence of GO in the nanocomposites, however, the addition of GO did not affect the crystal structure greatly. Thermal stability of PCL remarkably increased with the addition of GO nanosheets, compared with that of pure PCL. Incorporation of GO greatly improved the tensile strength and Young＇s modulus of PCL without a significant loss of the elongation at break.
基金financially supported by the National Natural Science Foundation of China(No.31500767)the Natural ScienceFoundation of Liaoning Province of China(No.20180510037)the Fundamental Research Funds for the Central Universities(No.DUT19LAB27)。
文摘X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications.
基金financially supported by the National Natural Science Foundation of China (Nos. 31000427, 50901011,81271719, 81271720)the Fundamental Research Funds for the Central Universities (DUT12JB09)
文摘A series of magnetic nanoeomposites based on poly（s-caprolactone） （PCL） and Fe3O4 nanoparticles were prepared using a facile in situ polymerization method. The chemical structures of the PCL/Fe3O4 nanocomposites were characterized by Fourier transform infrared （FTIR） spectroscopy. Results of wide-angle X-ray diffraction （WAXD） showed that the incorporation of the Fe3O4 nanoparticles did not affect the crystallization structure of the PCL. Both scanning electron microscopy （SEM） and transmission electron microscopy （TEM） were used to characterize the morphology and dispersion of the Fe3O4 nanoparticles within the as-synthesized nanocomposites. Results of differential scanning calorimetry （DSC） and polarizing optical microscopy （POM） showed that the crystallization temperature was raised and the spherulites size decreased by the presence of Fe3O4 nanoparticles in the nanocomposites due to the heterogeneous nucleation effect. The thermal stability of the PCL was depressed by incorporation of Fe3O4 nanoparticles from thermogravimetric analysis （TGA）. The superparamagnetic behavior of the PCL/Fe3O4 nanocomposites was testified by the superconducting quantum interference device （SQUID） magnetometer analysis. The obtained biodegradable nanocomposites will have a great potential in magnetic resonance imaging contrast and targeted drug delivery.
基金the financial support of the project from the National Natural Science Foundation of China(No.31500767)China Postdoctoral Science Foundation(2015M571300)+1 种基金the Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(No.20180510037)the Fundamental Research Funds for the Central Universities(DUT19LAB27)。
文摘The aim of the current study is to report an inherently radiopaque drug-eluted beads(DEBs)as promising embolic materials for TACE techniques.Firstly,the synthesized radiopaque iodinated polycaprolactonepolyurethanes(I-PCLUs)are synthesized by chain-extending method by using 4,4-′isopropylidinedi-(2,6-diiodophenol)(IBPA)as the radiopacifying agent.Then,doxorubicin(Dox)is introduced as a chemotherapeutic agent into I-PCLU beads via a double emulsification(W/O/W)method.The drug loading and controlled release behavior of two ratios of I-PCLU/Dox are found to be dependent upon the internal porous microstructure,and the radiopacity is well-retained after four weeks drug release.Besides,the I-PCLU/Dox beads exhibit positive in vitro anti-tumor effect.The in vivo intramuscular implantation and liver embolization results demonstrate that I-PCLU beads have good histocompatibility,occlusion effect and X-ray traceability.Furthermore,the drug-loaded I-PCLU beads are performed into a VX2 rabbit hepatocellular carcinoma(HCC)model using a micro-catheter,form embolization of hepatic arteries and inhibit the tumor growth after one week post-injection.Hence,this polymeric system provides a potential radiopaque chemoembolization candidate for HCC and other cancer therapies,which could bring opportunities to the next generation of multifunctional embolic agents.
