羟基磷灰石-明胶复合物的制备及表征

对均相沉淀法制备HAP-GEL粉体及溶胶进行了研究,结果表明:采用均相沉淀法可以制得小尺寸且分布均匀的颗粒;HAP-GEL溶胶可以稳定三个月以上;热分析图谱及TEM照片表明,在HAP-GEL结构中HAP微晶和GEL高分子产生了键连作用,且HAP沿着GEL纤维上呈现自组装结构。初步探索了Ca∶P、pH值、温度、搅拌强度、滴加速度、超声时间对产物性能、尺寸及稳定性的影响。采用琼脂糖凝胶电泳和钙红染色法对制备的HAP-GEL作了表面电位定性测试。     

超声时间对羟基磷灰石/明胶复合材料生物学性能的影响

在湿法共沉淀制备羟基磷灰石/明胶复合材料的基础上,采用超声辅助处理,重点研究了超声时间对复合材料生物学性能的影响,研究表明,超声处理3 h制备的复合材料两相分布均匀,材料内部呈支架结构,具有良好的生物降解性能和生物活性,可作为临床骨修复材料使用.     

羟基磷灰石明胶复合材料的研究进展

主要是介绍羟基磷灰石明胶复合材料的研究进展。分析了羟基磷灰石明胶物理复合方法和化学复合方法。及该系统在其他方面的应用．最后对羟基磷灰石明胶复合材料的发展进行了展望。     

超声处理对羟基磷灰石／明胶复合材料性能的影响

为了研究超声反应对制备羟基磷灰石/明胶复合材料的影响,制备性能优异的生物材料,在湿法共沉淀制备羟基磷灰石/明胶复合材料的基础上,采用超声处理,并采用戊二醛对明胶进行交联,重点研究了超声时间对复合材料结构和性能的影响.结果表明,超声处理3 h制备的复合材料的两相分布均匀,平均尺寸大约为30 nm×100 nm,平均长径比在2～3,晶粒形态与天然骨相似,其拉伸强度和抗压强度达到66.4 MPa和67.8 MPa.研究表明,超声处理3 h可以较好地改善羟基磷灰石的结晶状态,提高复合材料的力学性能.     

超声化学法合成羟基磷灰石-明胶复合材料

以Ca（NO3）2,（NH4）2HPO4,明胶和戊二醛为原料,用超声化学法合成了尺寸约为30nm×100nm,平均长径比在2-3,分散性良好的羟基磷灰石-明胶复合材料。对比研究了超声化学法与传统化学沉淀法对复合材料结晶性能和力学性能的影响。结果表明,与传统化学沉淀法相比,超声化学法可以在较短时间内显著提高羟基磷灰石的结晶度、改善结晶状态,使复合材料的抗拉强度和抗压强度分别达到52．4MPa和56．8MPa。     

碱法骨明胶促进纳米羟基磷灰石制备的研究

本文主要采用化学沉淀法,以碱法骨明胶为功能助剂,在室温下诱导合成羟基磷灰石,并对合成产物进行XRD,SEM表征。结果表明:碱法骨明胶可以促进羟基磷灰石的合成,且合成产物展现了很好的分散性,平均尺寸在40nm～80nm。碱法明胶与酸法明胶相比促进合成效果较好,随着碱法骨明胶含量的增加,羟基磷灰石的结晶度增加,粒径先增大后减小。     

羟基磷灰石微球的制备方法

羟基磷灰石[Ca_5(PO_4)_3(OH),HA]是一种重要的生物医学材料,尤其是球形羟基磷灰石更兼具比表面积大、流动性好和载药量高等特点,使其非常适于作为硬组织修复的基础材料,本文对现有球形羟基磷灰石(HA)的制备方法进行了综述,对各种制备方法所得微球的结构和尺寸大小作了比较,并对微球的成因进行了初步探讨。     

羟基磷灰石陶瓷微球的制备研究

羟基磷灰石陶瓷微球的流动性好、容易填充,近年来在骨修复,尤其是口腔手术中得到较多应用。以HA-(NaPO3)6-Mg(H2PO4)2-明胶为陶瓷浆料,应用液滴-冷凝法对羟基磷灰石陶瓷微球的制备工艺进行了探索研究,获得了球形度好、粒径均一的陶瓷微球。     

固相离子交换法制备碳酸羟基磷灰石涂层的研究

通过涂覆-烧结法在氧化铝(Al2O3)基体上制备羟基磷灰石(HA)/氟羟基磷灰石(FHA)双层涂层,然后采用固相离子交换法在湿CO2气氛中对HA表层进行碳酸化处理。XRD、FTIR和SEM测试结果表明:FHA中间层能有效地抑制HA与Al2O3的反应,湿CO2气氛中的湿气有利于分解相的恢复,而碳酸根能进入到表面涂层结构内部,形成A型替代为主的碳酸羟基磷灰石(CHA)。所获得的双层涂层具有多孔粗糙的表面,但与Al2O3基体结合紧密。     

生物活性梯度涂层中羟基磷灰石的相转变与结构稳定性

重点研究了生物活性梯度涂层中羟基磷灰石高温结构稳定性。探讨了羟基磷灰石在喷涂和热处理过程中的相变化,对比研究了不同热处理条件对羟基磷灰石晶体稳定性和羟基恢复的影响。发现经等离子喷涂后的生物活性梯度涂层中的羟基磷灰石结晶程度明显降低,并出现β－ＴＣＰ杂相。羟基磷灰石晶体中的羟基已完全分解脱落。适当条件的热处理可使喷涂涂层中的磷酸三钙转变为羟基磷灰石,晶体中的羟基可大部分恢复,其中大气热处理比真空热处     

Properties of New Composite Materials Based on Hydroxyapatite Ceramic and Cross-Linked Gelatin for Biomedical Applications

The main aim of the research was to develop a new biocompatible and injectable composite with the potential for application as a bone-to-implant bonding material or as a bone substitute. A composite based on hydroxyapatite, gelatin, and two various types of commercially available transglutaminase (TgBDF/TgSNF), as a cross-linking agent, was proposed. To evaluate the impacts of composite content and processing parameters on various properties of the material, the following research was performed: the morphology was examined by SEM microscopy, the chemical structure by FTIR spectroscopy, the degradation behavior was examined in simulated body fluid, the injectability test was performed using an automatic syringe pump, the mechanical properties using a nanoindentation technique, the surface wettability was examined by an optical tensiometer, and the cell viability was assayed by MTT and LDH. In all cases, a composite paste was successfully obtained. Injectability varied between 8 and 15 min. The type of transglutaminase did not significantly affect the surface topography or chemical composition. All samples demonstrated proper nanomechanical properties with Young’s modulus and the hardness close to the values of natural bone. BDF demonstrated better hydrophilic properties and structural stability over 7 days in comparison with SNF. In all cases, the transglutaminase did not lead to cell necrosis, but cellular proliferation was significantly inhibited, especially for the BDF agent.     

A Biomimetic Hybrid Hydrogel Based on the Interactions between Amino Hydroxyapatite and Gelatin/Gellan Gum

In this work, a gelatin (Gel)‐oxidized gellan gum (OG)/amino hydroxyapatite (mHap) hybrid hydrogel with Schiff base linkages is reported. The mHap is obtained by modifying hydroxyapatite with tetraethyl orthosilicate and 3‐aminopropyl‐triethoxysilane. The effects of different mHap contents on the structure, morphology, and properties of hydrogels are particularly investigated. Scanning electron microscopy coupled with energy dispersion spectroscopy reveals that mHap of around 100 nm is uniformly distributed inside the hydrogel with interconnected porous structures. Notably, the hydrogel with 1 wt% mHap possesses the highest compressive stress (2.01 ± 0.10 MPa) at 90% strain, as well as the lowest equilibrium swelling ratio (97% ± 5%) and degradation rate than other hydrogels. Besides, an ultra‐high compressive stress equivalent to 91% of the initial stress can be obtained by this hydrogel after 50 loading‐unloading cycles (85% strain). Meanwhile, after being swollen, this improved hydrogel also exhibits better structural stability than Gel‐OG hydrogel. The in vitro 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay further shows that all hydrogels are nontoxic against mouse fibroblasts. This work provides a biomimetic strategy to construct the organic/inorganic hydrogels with excellent interactions, elasticity, reversibility, and biocompatibility, which is of great importance for the practical applications in cartilage tissue engineering.     

Printability of Methacrylated Gelatin upon Inclusion of a Chloride Salt and Hydroxyapatite Nano‐Particles

3D biomaterial printing requires an ink to have suitable printability characteristics, as well as creating a final construct of controllable swelling and stiffness. To tune such properties, the impact of adding different levels of chloride salts (NaCl and CaCl₂) and hydroxyapatite nano‐particles (nHA) to a highly concentrated and photo‐crosslinkable methacrylated gelatin (GelMA) is investigated. By adding up to 100 mm CaCl₂ or 1.11 m NaCl, the GelMA viscosity decreases from that of control GelMA (no salt). Interestingly, a 25G needle and strong photo‐polymerization kinetics are able to overcome the low viscosity of the 50CaG ink during printing. Adding further CaCl₂ increases GelMA viscosity, while decreasing both the swelling and dynamic modulus of the UV‐cured construct observed in water. As all UV‐cured constructs have a dynamic modulus greater than 1 MPa, this novel system is able to match the dynamic modulus of articular cartilage—a feat not previously reported for a GelMA‐based system. Lastly, nHA inclusion improves ink printability, as well as decreases swelling and increases dynamic modulus of the final construct. Overall, this study leads to the successful development of a new advanced functional ink which will be beneficial in the 3D printing of biomaterials toward tissue engineering applications.     

溶胶凝胶法制备钛基羟基磷灰石涂层的研究

混合硝酸钙乙醇溶液和磷酸三甲酯水溶液作为羟基磷灰石(HA)前驱体,利用旋转涂膜技术在钛片表面制备羟基磷灰石涂层.研究了溶胶陈化时间和凝胶热处理温度对涂膜的影响,同时对涂层的生物活性进行了研究.样品利用X射线衍射仪(XRD)和扫描电子显微镜(ESEM)进行表征.结果表明:利用经过24 h陈化的溶胶涂膜的样品在500℃热处...     

气相扩散法合成不同形貌羟基磷灰石微球

利用简单的氨气扩散的方法分别合成出了花状多孔和空心微球羟基磷灰石,研究了磷酸根浓度和非离子表面活性剂PVA对最终产物羟基磷灰石形貌的影响,并用场发射扫描电子显微镜(FESEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射等方法对所得产物进行了表征.研究结果显示,在不含有PVA的溶液中,最初形成的物质为无定形磷酸钙(ACP),其随后转变为花状羟基磷灰石;增加磷酸根的浓度而保持钙离子浓度不变,得到的最终产物为空心羟基磷灰石微球.在溶液中加入非离子表面活性剂PVA,无论是否改变磷酸根浓度,得到的产物均为花状羟基磷灰石.     

Effects of Yttria-Stabilized Zirconia on Plasma-Sprayed Hydroxyapatite/Yttria-Stabilized Zirconia Composite Coatings

The low bonding strength between hydroxyapatite (HA) and the metal substrate interface of plasma-sprayed HA coating has been a point of potential weakness in its application as a biomedical prosthesis. In the present study, yttria-stabilized (8 wt%) zirconia (YSZ) has been used to enhance the mechanical properties of HA coatings. The effects of YSZ additions (in the range 10–50 wt%) on the phase composition, microstructure, bond strength, elastic modulus, and fracture toughness of plasma-sprayed HA/YSZ composite coatings have been studied. The results indicated that decomposition of HA during plasma spraying was reduced significantly with the addition of zirconia. The higher the zirconia content, the lower the amount of calcium oxide, tricalcium phosphate, and tetracalcium phosphate formed in the coatings. In addition, there was a trace of calcium zirconate formed when less than 30 wt% zirconia was present. A solid solution of HA mixed with YSZ formed during plasma spraying; however, the amount of unmelted particles increased as the zirconia increased. The mechanical properties of the HA/YSZ composite coatings, such as bond strength, elastic modulus, and fracture toughness, increased significantly as the contents of zirconia increased.     

再生丝素蛋白/羟基磷灰石多孔复合材料的制备

再生丝素蛋白具有良好的生物相容性,羟基磷灰石同时还具有成骨诱导性。通过将再生丝素蛋白制备形成丝素蛋白多孔材料,并在37℃下将其浸渍于模拟体液中可以制备再生丝素蛋白/羟基磷灰石多孔复合材料。扫描电镜研究发现在再生丝素蛋白多孔材料的孔隙中羟基磷灰石由针状晶体聚集而成,红外光谱和XRD等表征表明复合材料中羟基磷灰石以羰基取代的羟基磷灰石存在。制备的再生丝素蛋白/羟基磷灰石多孔材料有望作为骨组织修复材料使用。     

温度对甲壳素/明胶复合膜的影响

用明胶为原料（基体）,以甘油作为增塑剂,甲壳素作为增强相,制备一系列不同含量的甲壳素/明胶复合膜。在5、20、35（±1） ℃环境之中,测试其拉伸强度、断裂伸长率、水蒸气透过系数（WVP）、水溶性和失水率,探究温度对甲壳素/明胶复合膜的影响。结果表明,温度对复合膜的性能影响较大,35 ℃时拉伸强度为77.34~44.44 MPa,但断裂伸长率较低（13.35 %~2.75 %）,5 ℃时拉伸强度为6.06~4.75 MPa,断裂伸长率为111.4 %~64.2 %,低温时断裂伸长率较大,但拉伸强度较小,高温则相反;WVP随温度的升高而逐渐增加;水溶性随温度的升高而逐渐增大;甲壳素含量越大,复合膜内的水分子含量越少。     

3D Printable Composite Biomaterials Based on GelMA and Hydroxyapatite Powders Doped with Cerium Ions for Bone Tissue Regeneration

The main objective was to produce 3D printable hydrogels based on GelMA and hydroxyapatite doped with cerium ions with potential application in bone regeneration. The first part of the study regards the substitution of Ca²⁺ ions from hydroxyapatite structure with cerium ions (Ca_10-xCe_x(PO₄)₆(OH)₂, xCe = 0.1, 0.3, 0.5). The second part followed the selection of the optimal concentration of HAp doped, which will ensure GelMA-based scaffolds with good biocompatibility, viability and cell proliferation. The third part aimed to select the optimal concentrations of GelMA for the 3D printing process (20%, 30% and 35%). In vitro biological assessment presented the highest level of cell viability and proliferation potency of GelMA-HC5 composites, along with a low cytotoxic potential, highlighting the beneficial effects of cerium on cell growth, also supported by Live/Dead results. According to the 3D printing experiments, the 30% GelMA enriched with HC5 was able to generate 3D scaffolds with high structural integrity and homogeneity, showing the highest suitability for the 3D printing process. The osteogenic differentiation experiments confirmed the ability of 30% GelMA-3% HC5 scaffold to support and efficiently maintain the osteogenesis process. Based on the results, 30% GelMA-3% HC5 3D printed scaffolds could be considered as biomaterials with suitable characteristics for application in bone tissue engineering.