Synthesis of Amino-Functionalized Hexagonal Mesoporous Silica for Adsorption of Pb2＋

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.

Octacalcium Phosphate Fiber Synthesized by Homogeneous Precipitation Method

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.

Improved the biocompatibility of cancellous bone with compound physicochemical decellularization process

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.