In order to improve the wettability and biocompatibility of the poly （butylene terephthalate） non-woven （PBTNW）, the method of surface modification is used to graft copolymerization of chitosan （CS） onto the PBT...In order to improve the wettability and biocompatibility of the poly （butylene terephthalate） non-woven （PBTNW）, the method of surface modification is used to graft copolymerization of chitosan （CS） onto the PBTNW under alkylpolyglycoside （APG） inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy （FrIR）, the electron spectroscopy for chemical analysis （ESCA）, the thermogravimetric （TG） and the scanning electron microscopy （SEM）. It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications.展开更多
Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wista...Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wistar rats were orally fed high fat emulsion and received sulfate chitosan derivatives for 5 weeks to determine the pre-treatment effect of sulfate chitosan derivatives on NAFLD. To evaluate the therapeutic effect of sulfate chitosan derivatives on NAFLD, the rats were orally fed with high concentration emulsion for 5 weeks, followed by sulfate chitosan derivatives for 3 weeks. Histological analysis and biomedical assays showed that sulfate chitosan derivatives can dramatically prevent the development of hepatic steatosis in hepatocyte cells. In animal studies, pre-treatment and treatment with sulfate chitosan derivatives significantly protected against hepatic steatohepatitis induced by high fat diet according to histological analysis. Furthermore, increased TC, ALT, MDA, and LEP in NAFLD were significantly ameliorated by pre-treatment and treatment with sulfate chitosan derivatives. Furthermore, increased TG, AST, and TNF-α in NAFLD were significantly ameliorated by treatment with sulfate chitosan derivatives. Sulfate chitosan derivatives have good pre-treatment and therapeutic effect on NAFLD.展开更多
Acid functionalized single walled carbon nanotubes （CNTs） were grafted to chitosan by first reacting the oxidized CNTs with thionyl chloride to form acyl-chlorinated CNTs. This product was subsequently dispersed in ...Acid functionalized single walled carbon nanotubes （CNTs） were grafted to chitosan by first reacting the oxidized CNTs with thionyl chloride to form acyl-chlorinated CNTs. This product was subsequently dispersed in chitosan and covalently grafted to form CNT-chitosan. CNT-chitosan was further grafted onto 3-trimethoxysilylpropyl methacrylate by free radical polymerization conditions, to yield CNT-g-chitosan-g-3-trimethoxysilylpropyl methacrylate （TMSPM）, hereafter referred to as CNT-chitosan-3-TMSPM. These composites were characterized by Fourier Transform Infrared Resonance Spectroscopy （FTIR）, carbon-13 nuclear magnetic resonance （13C NMR）, Yhermogravimetric Analysis （TGA）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The composite showed improved thermal stability and could be of great potential use in bone tissue engineering.展开更多
Porous silicon nanoparficles （pSiNPs） are a promising nanocarrier system for drug delivery owing to their biocompatibility, biodegradability, and non-inflammatory nature. Here, we investigate the fabrication and cha...Porous silicon nanoparficles （pSiNPs） are a promising nanocarrier system for drug delivery owing to their biocompatibility, biodegradability, and non-inflammatory nature. Here, we investigate the fabrication and characterization of thermally hydrocarbonized pSiNPs （THCpSiNPs） and chitosan-coated THCpSiNPs for therapeutic oligonucleotide delivery. Chitosan coating after oligonucleotide loading significantly improves sustained oligonucleotide release and suppresses burst release effects. Moreover, cellular uptake, endocytosis, and cytotoxicity of oligonucleotide-loaded THCpSiNPs have been evaluated in vitro. Standard cell viability assays demonstrate that cells incubated with the NPs at a concentration of 0.1 mg/mL are 95% viable. In addition, chitosan coating significantly enhances the uptake of oligonucleotide-loaded THCpSiNPs across the cell membrane. Moreover, histopathological analysis of liver, kidney, spleen, and skin tissue collected from mice receiving NPs further demonstrates the biocompatible and non-inflammatory properties of the NPs as a gene delivery vehicle for intravenous and subcutaneous administration in vivo. Taken together, these results suggest that THCpSiNPs provide a versatile platform that could be used as efficient vehicles for the intracellular delivery of oligonucleotides for gene therapy.展开更多
For the requirement of preliminary vascularization, the scaffolds for thick tissue engineering should have not only good cell affinity, but also anticoagulant ability. In this paper, enzymatically cross-linked hydroge...For the requirement of preliminary vascularization, the scaffolds for thick tissue engineering should have not only good cell affinity, but also anticoagulant ability. In this paper, enzymatically cross-linked hydrogel scaffolds based on sulfated chitosan （SCTS） were prepared. Firstly, sulfated chitosan-hydroxyphenylpionic acid （SCTS-HPA） conjugate was synthesized, and the structure of SCTS-HPA was identified by FITR and ~H NMR. And then the enzymatically cross-linked hydrogels were pre- pared in presence of horseradish peroxidase （HRP） and hydrogen peroxide （H202）. The gelation time, mechanical property, morphology and cytotoxicity to human umbilical vein endothelial cells （HUVECs） of the hydrogel were evaluated in vitro, the tissue compatibility of SCTS-HPA scaffold was studied in vivo. The results showed that the gelation time, mechanical property, morphology of the dehydrated hydrogel could be controlled by the the concentration of HRP and H202. The cytotoxicity test showed that the hydrogel extracts have no cytotoxicity to HUVECs. The in vivo assay indicated that SCTS-HPA scaffold have good tissue compatibility with no thrombus formation. All these results indicated that the SCTS-HPA scaffold could be used as a thick tissue engineering scaffold.展开更多
文摘In order to improve the wettability and biocompatibility of the poly （butylene terephthalate） non-woven （PBTNW）, the method of surface modification is used to graft copolymerization of chitosan （CS） onto the PBTNW under alkylpolyglycoside （APG） inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy （FrIR）, the electron spectroscopy for chemical analysis （ESCA）, the thermogravimetric （TG） and the scanning electron microscopy （SEM）. It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications.
基金supported by the National High Technology Research and Development Program of China (863 Program 2006AA090401)
文摘Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wistar rats were orally fed high fat emulsion and received sulfate chitosan derivatives for 5 weeks to determine the pre-treatment effect of sulfate chitosan derivatives on NAFLD. To evaluate the therapeutic effect of sulfate chitosan derivatives on NAFLD, the rats were orally fed with high concentration emulsion for 5 weeks, followed by sulfate chitosan derivatives for 3 weeks. Histological analysis and biomedical assays showed that sulfate chitosan derivatives can dramatically prevent the development of hepatic steatosis in hepatocyte cells. In animal studies, pre-treatment and treatment with sulfate chitosan derivatives significantly protected against hepatic steatohepatitis induced by high fat diet according to histological analysis. Furthermore, increased TC, ALT, MDA, and LEP in NAFLD were significantly ameliorated by pre-treatment and treatment with sulfate chitosan derivatives. Furthermore, increased TG, AST, and TNF-α in NAFLD were significantly ameliorated by treatment with sulfate chitosan derivatives. Sulfate chitosan derivatives have good pre-treatment and therapeutic effect on NAFLD.
文摘Acid functionalized single walled carbon nanotubes （CNTs） were grafted to chitosan by first reacting the oxidized CNTs with thionyl chloride to form acyl-chlorinated CNTs. This product was subsequently dispersed in chitosan and covalently grafted to form CNT-chitosan. CNT-chitosan was further grafted onto 3-trimethoxysilylpropyl methacrylate by free radical polymerization conditions, to yield CNT-g-chitosan-g-3-trimethoxysilylpropyl methacrylate （TMSPM）, hereafter referred to as CNT-chitosan-3-TMSPM. These composites were characterized by Fourier Transform Infrared Resonance Spectroscopy （FTIR）, carbon-13 nuclear magnetic resonance （13C NMR）, Yhermogravimetric Analysis （TGA）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The composite showed improved thermal stability and could be of great potential use in bone tissue engineering.
文摘Porous silicon nanoparficles （pSiNPs） are a promising nanocarrier system for drug delivery owing to their biocompatibility, biodegradability, and non-inflammatory nature. Here, we investigate the fabrication and characterization of thermally hydrocarbonized pSiNPs （THCpSiNPs） and chitosan-coated THCpSiNPs for therapeutic oligonucleotide delivery. Chitosan coating after oligonucleotide loading significantly improves sustained oligonucleotide release and suppresses burst release effects. Moreover, cellular uptake, endocytosis, and cytotoxicity of oligonucleotide-loaded THCpSiNPs have been evaluated in vitro. Standard cell viability assays demonstrate that cells incubated with the NPs at a concentration of 0.1 mg/mL are 95% viable. In addition, chitosan coating significantly enhances the uptake of oligonucleotide-loaded THCpSiNPs across the cell membrane. Moreover, histopathological analysis of liver, kidney, spleen, and skin tissue collected from mice receiving NPs further demonstrates the biocompatible and non-inflammatory properties of the NPs as a gene delivery vehicle for intravenous and subcutaneous administration in vivo. Taken together, these results suggest that THCpSiNPs provide a versatile platform that could be used as efficient vehicles for the intracellular delivery of oligonucleotides for gene therapy.
基金supported by the National Basic Research Program of China(973 Project,2011CB606202)the National Natural Science Foundation of China(51273095)
文摘For the requirement of preliminary vascularization, the scaffolds for thick tissue engineering should have not only good cell affinity, but also anticoagulant ability. In this paper, enzymatically cross-linked hydrogel scaffolds based on sulfated chitosan （SCTS） were prepared. Firstly, sulfated chitosan-hydroxyphenylpionic acid （SCTS-HPA） conjugate was synthesized, and the structure of SCTS-HPA was identified by FITR and ~H NMR. And then the enzymatically cross-linked hydrogels were pre- pared in presence of horseradish peroxidase （HRP） and hydrogen peroxide （H202）. The gelation time, mechanical property, morphology and cytotoxicity to human umbilical vein endothelial cells （HUVECs） of the hydrogel were evaluated in vitro, the tissue compatibility of SCTS-HPA scaffold was studied in vivo. The results showed that the gelation time, mechanical property, morphology of the dehydrated hydrogel could be controlled by the the concentration of HRP and H202. The cytotoxicity test showed that the hydrogel extracts have no cytotoxicity to HUVECs. The in vivo assay indicated that SCTS-HPA scaffold have good tissue compatibility with no thrombus formation. All these results indicated that the SCTS-HPA scaffold could be used as a thick tissue engineering scaffold.
