Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical ...Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.展开更多
The calcium phosphate coatings were prepared by virtue of electrochemical deposition in order to improve the corrosion resistance of Mg-1.0Ca alloys in simulated body fluids.The chemical compositions,structures and mo...The calcium phosphate coatings were prepared by virtue of electrochemical deposition in order to improve the corrosion resistance of Mg-1.0Ca alloys in simulated body fluids.The chemical compositions,structures and morphologies of the coatings were investigated by energy dispersive spectroscopy(EDS),X-ray diffractometry(XRD)and scanning electron microscopy(SEM), respectively.The potentiodynamic electrochemical technique was employed to investigate the bio-degradation behavior of Mg-1.0Ca alloys with Ca-P coatings in Hank's solutions.The experimental results show that the deposited coatings predominately consist of flake-shape brushite(DCPD,CaHPO4·2H2O)crystallites.The corrosion resistance of the substrates with coatings is improved in Hank's solutions significantly.展开更多
基金financially supported by National High Technology Research and Development Program of China(863 Program,Grant No.2007AA091603)
文摘Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.
基金Projects(CSTC2009AB4008)supported by Key Technologies R&D Program and Natural Science Foundation of Chongqing Science and Technology Commission,ChinaProject(KJ100808,KJ08065)supported by Science and Technology Research Fund of Chongqing Municipal Education Commission,China
文摘The calcium phosphate coatings were prepared by virtue of electrochemical deposition in order to improve the corrosion resistance of Mg-1.0Ca alloys in simulated body fluids.The chemical compositions,structures and morphologies of the coatings were investigated by energy dispersive spectroscopy(EDS),X-ray diffractometry(XRD)and scanning electron microscopy(SEM), respectively.The potentiodynamic electrochemical technique was employed to investigate the bio-degradation behavior of Mg-1.0Ca alloys with Ca-P coatings in Hank's solutions.The experimental results show that the deposited coatings predominately consist of flake-shape brushite(DCPD,CaHPO4·2H2O)crystallites.The corrosion resistance of the substrates with coatings is improved in Hank's solutions significantly.
