Hydroxyapatite(HAP)/Chitosan(CS) composite is a biocompatible and bioactive material for tissue engineering. A novel homogeneous HAP/CS composite scaffold was developed via lyophilization and in situ hydration. A mode...Hydroxyapatite(HAP)/Chitosan(CS) composite is a biocompatible and bioactive material for tissue engineering. A novel homogeneous HAP/CS composite scaffold was developed via lyophilization and in situ hydration. A model CS solution with a Ca/P atom ratio of 1.67 was prepared through titration and stirring so as to attain a homogeneous dispersion of HAP particles. After lyophilization and in situ hydration, rod-shaped HAP particles (5 μm in diameter) within the CS matrix homogeneously scattered at the pore wall of the CS scaffold. X-ray diffraction (XRD) and Fouri-er-Transformed Infrared spectroscopy (FTIR) confirmed the formation of HAP crystals. The compressive strength in the composite scaffold indicated a significant increment over a CS-only scaffold. Bioactivity in vitro was completed by immersing the scaffold in simulated body fluid (SBF), and the result suggested that there was an increase in apatite formation on the HAP/CS scaffolds. Biological in vivo cell culture with MC 3T3-E1 cells for up to 7 days demonstrated that a homogeneous incorporation of HAP particles into CS scaffold led to higher cell viability compared to that of the pure CS scaffold or the HAP/CS scaffold blended. The results suggest that the homogeneous composite scaffold with better strength, bioactivity and biocompatibility can be prepared via in vitro hydration, which may serve as a good scaffold for bone tissue engineering.展开更多
With a homogeneous distribution of hydroxyapatite （HAP） crystals in polymer matrix, composite scaffolds chitosan/HAP and chitosanJcollagen/HAP were fabricated in the study. XRD, SEM and EDX were used to characterize...With a homogeneous distribution of hydroxyapatite （HAP） crystals in polymer matrix, composite scaffolds chitosan/HAP and chitosanJcollagen/HAP were fabricated in the study. XRD, SEM and EDX were used to characterize their components and structure, in vitro cell culture and in vivo animal tests were used to evaluate their biocompatibility. HAP crystals with rod-like shape embeded in chitosan scaffold, while HAP fine-granules bond with collagen/chitosan scaffold compactly. A homogenous distribution of Ca and P elements both in chitosan/HAP scaffold and chitosan/collagen/HAP scaffold was defined by EDX pattern. The presence of collagen brought a more homogenous distribution of HAP due to its higher ability to induce HAP precipitation. The results of in vitro cell culture showed that the composite＇s biocompatibility was enhanced by the homogenous distribution of HAP. In vivo animal studies showed that the in vivo biodegradation was effectively improved by the addition of HAP and collagen, and was less influenced by the homogeneous distribution of HAP when compared with a concentrated distribution one. The composite scaffolds with a homogeneous HAP distribution would be excellent alternative scaffolds for bone tissue engineering.展开更多
Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone tissue engineering. A new bone repair scaffold was generated by thorough mixing of icariin and chitosan/ hydroxyapatite ...Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone tissue engineering. A new bone repair scaffold was generated by thorough mixing of icariin and chitosan/ hydroxyapatite (icariin-CS/HA) using freeze-drying technigue. Characteristics of morphology, mechanical properties, biocompatibility, drug release behavior and bone repair abilities in vivo were evaluated. The results show that drug loading process of icariin did not affect physical structure of CS/HA composite significantly but decreased mechanical properies of CS/HA composite, which happened with a high dosage; icariin-CS/HA had favorable cell compatibility and promoted osteogenic differentiation of hBMSCs; the controlled release of icariin was satisfactory and the release retained after 90 d in vitro. In addition, icariin-CS/HA scaffolds had favorable osteoconduction and osteoinduction in vivo, and could fill bone defect sites and stimulate newborn bone tissues formation at early stage. On the basis of these data, icariin-CS/HA is believed to be an optical bone repair scaffold for tissue engineering.展开更多
以16.7%(质量分数)的柠檬酸水溶液作溶剂,通过粒子沥滤法制备了 n HA/CS多孔材料,并对其进行了IR、XRD、SEM、孔隙率及力学性能测试。结果表明n HA/CS复合材料中羟基磷灰石呈弱结晶状态,复合前后两组分的化学组成未发生显著变化,但两相...以16.7%(质量分数)的柠檬酸水溶液作溶剂,通过粒子沥滤法制备了 n HA/CS多孔材料,并对其进行了IR、XRD、SEM、孔隙率及力学性能测试。结果表明n HA/CS复合材料中羟基磷灰石呈弱结晶状态,复合前后两组分的化学组成未发生显著变化,但两相间发生了相互作用。多孔材料呈高度多孔结构,孔壁上富含微孔,孔间贯通性高;复合材料/致孔剂质量比为1时,多孔材料的孔隙率为 53%,其抗压强度可达17 MPa左右,可以满足组织工程支架材料的要求。展开更多
文摘Hydroxyapatite(HAP)/Chitosan(CS) composite is a biocompatible and bioactive material for tissue engineering. A novel homogeneous HAP/CS composite scaffold was developed via lyophilization and in situ hydration. A model CS solution with a Ca/P atom ratio of 1.67 was prepared through titration and stirring so as to attain a homogeneous dispersion of HAP particles. After lyophilization and in situ hydration, rod-shaped HAP particles (5 μm in diameter) within the CS matrix homogeneously scattered at the pore wall of the CS scaffold. X-ray diffraction (XRD) and Fouri-er-Transformed Infrared spectroscopy (FTIR) confirmed the formation of HAP crystals. The compressive strength in the composite scaffold indicated a significant increment over a CS-only scaffold. Bioactivity in vitro was completed by immersing the scaffold in simulated body fluid (SBF), and the result suggested that there was an increase in apatite formation on the HAP/CS scaffolds. Biological in vivo cell culture with MC 3T3-E1 cells for up to 7 days demonstrated that a homogeneous incorporation of HAP particles into CS scaffold led to higher cell viability compared to that of the pure CS scaffold or the HAP/CS scaffold blended. The results suggest that the homogeneous composite scaffold with better strength, bioactivity and biocompatibility can be prepared via in vitro hydration, which may serve as a good scaffold for bone tissue engineering.
基金the National High Technology Development Program (No. 2007AA091603)the National Natural Science Foundation of China (Nos. 30870612 and 20604010)
文摘With a homogeneous distribution of hydroxyapatite （HAP） crystals in polymer matrix, composite scaffolds chitosan/HAP and chitosanJcollagen/HAP were fabricated in the study. XRD, SEM and EDX were used to characterize their components and structure, in vitro cell culture and in vivo animal tests were used to evaluate their biocompatibility. HAP crystals with rod-like shape embeded in chitosan scaffold, while HAP fine-granules bond with collagen/chitosan scaffold compactly. A homogenous distribution of Ca and P elements both in chitosan/HAP scaffold and chitosan/collagen/HAP scaffold was defined by EDX pattern. The presence of collagen brought a more homogenous distribution of HAP due to its higher ability to induce HAP precipitation. The results of in vitro cell culture showed that the composite＇s biocompatibility was enhanced by the homogenous distribution of HAP. In vivo animal studies showed that the in vivo biodegradation was effectively improved by the addition of HAP and collagen, and was less influenced by the homogeneous distribution of HAP when compared with a concentrated distribution one. The composite scaffolds with a homogeneous HAP distribution would be excellent alternative scaffolds for bone tissue engineering.
基金Supported by the National Basic Research Program (Grant No. 2009CB930000)National Natural Science Foundation of China (Grant No. 30700180)Chinese Postdoctoral Science Foundation (Grant No. 20060390206)
文摘Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone tissue engineering. A new bone repair scaffold was generated by thorough mixing of icariin and chitosan/ hydroxyapatite (icariin-CS/HA) using freeze-drying technigue. Characteristics of morphology, mechanical properties, biocompatibility, drug release behavior and bone repair abilities in vivo were evaluated. The results show that drug loading process of icariin did not affect physical structure of CS/HA composite significantly but decreased mechanical properies of CS/HA composite, which happened with a high dosage; icariin-CS/HA had favorable cell compatibility and promoted osteogenic differentiation of hBMSCs; the controlled release of icariin was satisfactory and the release retained after 90 d in vitro. In addition, icariin-CS/HA scaffolds had favorable osteoconduction and osteoinduction in vivo, and could fill bone defect sites and stimulate newborn bone tissues formation at early stage. On the basis of these data, icariin-CS/HA is believed to be an optical bone repair scaffold for tissue engineering.
