Highly ordered amino-functionalized hexagonal mesoporous silica (HMS-NH2) had been synthesized successfully by co-condensation. The resultant materials were characterized by means of XRD, TEM, FT-IR, N2 ad-desorptio...Highly ordered amino-functionalized hexagonal mesoporous silica (HMS-NH2) had been synthesized successfully by co-condensation. The resultant materials were characterized by means of XRD, TEM, FT-IR, N2 ad-desorption and 29Si NMR to confirm the ordered mesoporous structure and the functionalization of the amino groups. The sample was employed as a Pb2+ adsorbent in aqueous solutions at room temperature. Both Lagergren's first order kinetic model and Lagergren's second order kinetic model were used to describe the adsorption data. It was found that the pseudo second order model fitted the sorption kinetic data better than the pseudo first order model. According to the information analyzed from AAS, HMS-NH2 had a Pb2+ adsorption amount of over 90.7 mg·g-1 , showing a promising application for the treatment of wastewater containing Pb2+ ions.展开更多
Calcium phosphate fiber was synthesized by homogeneous precipitation method using urea as precipitation agent. Effects of the reactant concentration and hydrothermal temperature on the calcium phosphate morphology and...Calcium phosphate fiber was synthesized by homogeneous precipitation method using urea as precipitation agent. Effects of the reactant concentration and hydrothermal temperature on the calcium phosphate morphology and composition were studied using SEM, FTIR and XRD. It is found that fine octacalcium phosphate(OCP)fiber can be synthesized when the reactant concentrations are 0.167 mol/L for Ca(NO3)2, 0.1 mol/L for (NH4)2HPO4, and 0.6-0.7 mol/L for (NH2)2CO, respectively, with the initial reactant solution pH value around 2.2, hydrothermal temperature 90 ℃ and termination reaction at pH value around 5.0. At very low urea concentration, the product size distribution is highly inhomogeneous, however, at an excessively high concentration the product becomes larger and shorter and a mixture of OCP and hydroxyapatite (HA). Increasing the hydrothermal temperature is favorable to the fast precipitation of OCP, higher productivity and finer product.展开更多
Due to the unique microstructures and components of extracellular matrix(ECM),decellularized scaffolds had been used widely in clinical.The reaction of the host toward decellularized scaffolds depends on their biocomp...Due to the unique microstructures and components of extracellular matrix(ECM),decellularized scaffolds had been used widely in clinical.The reaction of the host toward decellularized scaffolds depends on their biocompatibility,which should be satisfied before applied in clinical.The aim of this study is to develop a decellularized xenograft material with good biocompatibility for further bone repair,in an effective and gentle method.The existing chemical and physical decellularization techniques including ethylene diamine tetraacetic acid(EDTA),sodium dodecyl sulfate(SDS)and supercritical carbon dioxide(SC-CO2)were combined and modified to decellularize bovine cancellous bone(CB).After decellularization,almost 100%of A-Gal epitopes were removed,the combination of collagen,calcium and phosphate was reserved.The direct and indirect contact with macrophages was used to evaluate the cytotoxicity and immunological response of the materials.Mesenchymal stem cells(MSCs)were used in the in vitro cells’proliferation assay.The decellularized CB was proved has no cytotoxicity(grade 1)and no immunological response(NO,IL-2,IL-6 and TNF-α secretion inhibited),and could support MSCs proliferated continuedly.These results were similar to that of commercial decellularized human bone.This study suggests the potential of using this kind of combine decellularization process to fabricate heterogeneous ECM scaffolds for clinical application.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 50732003, U0834003) and High Technology Study Plan of China (Nos. 2007AA021908, 2006AA03Z356).
文摘Highly ordered amino-functionalized hexagonal mesoporous silica (HMS-NH2) had been synthesized successfully by co-condensation. The resultant materials were characterized by means of XRD, TEM, FT-IR, N2 ad-desorption and 29Si NMR to confirm the ordered mesoporous structure and the functionalization of the amino groups. The sample was employed as a Pb2+ adsorbent in aqueous solutions at room temperature. Both Lagergren's first order kinetic model and Lagergren's second order kinetic model were used to describe the adsorption data. It was found that the pseudo second order model fitted the sorption kinetic data better than the pseudo first order model. According to the information analyzed from AAS, HMS-NH2 had a Pb2+ adsorption amount of over 90.7 mg·g-1 , showing a promising application for the treatment of wastewater containing Pb2+ ions.
基金Funded by the Guangzhou Municipal Science and Technology Bureau(No. 2008J1-C101)supported in part by the National Natural Science Foundation of China (No. 50803019)the Doctoral Program of Ministry of Education of China (No. 200805611030)
文摘Calcium phosphate fiber was synthesized by homogeneous precipitation method using urea as precipitation agent. Effects of the reactant concentration and hydrothermal temperature on the calcium phosphate morphology and composition were studied using SEM, FTIR and XRD. It is found that fine octacalcium phosphate(OCP)fiber can be synthesized when the reactant concentrations are 0.167 mol/L for Ca(NO3)2, 0.1 mol/L for (NH4)2HPO4, and 0.6-0.7 mol/L for (NH2)2CO, respectively, with the initial reactant solution pH value around 2.2, hydrothermal temperature 90 ℃ and termination reaction at pH value around 5.0. At very low urea concentration, the product size distribution is highly inhomogeneous, however, at an excessively high concentration the product becomes larger and shorter and a mixture of OCP and hydroxyapatite (HA). Increasing the hydrothermal temperature is favorable to the fast precipitation of OCP, higher productivity and finer product.
基金supported by National Natural Science Foundation of China(51502094)Special Fund Project for Guangdong Academy of Sciences to Build First-Class Research Institutions in China(2020GDASYL-20200103038)+4 种基金National Key R&D Plans(2018YFC1105902)China Postdoctoral Science Foundation(2017M612657)Guangdong Province Science and Technology Projects(2013B021800137)Pearl River Nova Program of Guangzhou(201610010168)Guangdong Province Medical Research Foundation(A2016060).
文摘Due to the unique microstructures and components of extracellular matrix(ECM),decellularized scaffolds had been used widely in clinical.The reaction of the host toward decellularized scaffolds depends on their biocompatibility,which should be satisfied before applied in clinical.The aim of this study is to develop a decellularized xenograft material with good biocompatibility for further bone repair,in an effective and gentle method.The existing chemical and physical decellularization techniques including ethylene diamine tetraacetic acid(EDTA),sodium dodecyl sulfate(SDS)and supercritical carbon dioxide(SC-CO2)were combined and modified to decellularize bovine cancellous bone(CB).After decellularization,almost 100%of A-Gal epitopes were removed,the combination of collagen,calcium and phosphate was reserved.The direct and indirect contact with macrophages was used to evaluate the cytotoxicity and immunological response of the materials.Mesenchymal stem cells(MSCs)were used in the in vitro cells’proliferation assay.The decellularized CB was proved has no cytotoxicity(grade 1)and no immunological response(NO,IL-2,IL-6 and TNF-α secretion inhibited),and could support MSCs proliferated continuedly.These results were similar to that of commercial decellularized human bone.This study suggests the potential of using this kind of combine decellularization process to fabricate heterogeneous ECM scaffolds for clinical application.