电泳沉积制备羟基磷灰石／生物玻璃梯度涂层的研究

本文研究了羟基磷灰石颗料，生物玻璃颗粒在醋酸介质中的电泳沉积规律，利用它们不同的沉积规律设计了羟基磷灰石／生物玻璃梯度沉积装置，用电子探针分析了涂层横截面元素分布，表明所设计的装置可实现羟基磷灰石和生物玻璃的梯度涂层。     

氧化锆基羟基磷灰石梯度涂层材料的研究

本文采用涂覆-烧结法制备了一种以氧化锆为基体的生物玻璃-羟基磷灰石梯度涂层材料，并对其热学、力学性能进行了测试实验发现，在生物玻璃-羟基磷灰石梯度设计时，羟基磷灰石含量对复合体材料的热膨胀性能有着较大的影响．这种影响的原因是，随着羟基磷灰石含量的变化，复合体材料的结构发生改变，从玻璃相为主晶相向羟基磷灰石为主晶相转变．文中对梯度涂层各层中的热应力进行了计算，其结果与涂层-基体的结合强度相吻合.     

氧化锆基羟基磷灰石梯度涂层材料的研究

本文采用涂覆－烧结法制备了一种以氧化锆为基体的生物玻璃－羟基磷灰石梯度涂层材料，并对其热学、力学性能进行了测试。实验发现，在生物玻璃－羟基磷灰石梯度设计时，羟基磷灰石含量对复合体材料的热膨胀性能有着较大的影响。这种影响的原因是，随着羟基磷在石含量的变化，复合体材料的结构发生改变，从玻璃相为主晶相向羟基磷灰石为主晶相转变。文中对梯度涂层各层中的热尖力进行了计算，其结果与涂层－基体的结合强度相吻合。     

羟基磷灰石/生物玻璃复合涂层的研究

设计了适合在Ti6Al4V金属基体上制备涂层的生物玻璃，通过电泳沉积以及后续热处理在Ti6Al4V合金上制备了羟基磷灰石／生物玻璃复合涂层，实现了底层致密表层多孔的结构梯度。利用平底锥头法对涂层剪切强度进行了测试；利用SEM观察了其表面形貌；利用EPMA分析了复合涂层断面结构和组成。     

电化学制备羟基磷灰石涂层的生物活性研究

应用电化学沉积方法在钛金属表面制得致密均匀的羟基磷灰石涂层;使用MG63人成骨肉瘤细胞的培养评价涂层的生物活性.结果表明电化学沉积方法制得的羟基磷灰石涂层具有优良的生物相容性,涂层的晶粒尺寸及涂层的微观形貌对涂层的生物性能有较大影响.     

声电沉积透钙磷石和羟基磷灰石涂层动力学对比研究

借助声电沉积技术，在碳／碳复合材料表面制备了生物活性透钙磷石和羟基磷灰石涂层。采用分析天平称量了不同温度和时间的涂层重量，通过理论分析研究了涂层沉积的动力学规律。结果表明随时间温度增加，涂层的质量增加。透钙磷石和羟基磷灰石沉积都受扩散过程控制，并且得出羟基磷灰石的扩散活化能是7．24Kcal／mol，透钙磷石的扩散活化能很小，在本实验范围内不能求出，但通过比较分析，可知透钙磷石的扩散活化能远小于羟基磷灰石涂层，因此从理论上揭示了声电沉积工艺中，透钙磷石优先羟基磷灰石涂层沉积的本质原因。     

碳纳米管/羟基磷灰石生物复合涂层的制备与微观结构研究

采用电泳沉积的方法在钛板表面制备了碳纳米管/羟基磷灰石复合涂层。XRD研究发现,复合涂层的成分主要是羟基磷灰石和碳纳米管;IR研究发现,复合涂层中含有羟基、磷酸根等官能团;SEM研究发现,复合涂层均匀致密,碳纳米管与羟基磷灰石颗粒混合均匀,且碳纳米管的表面已被1层羟基磷灰石薄膜均匀包覆。随着碳纳米管含量从20%增加到40%,复合涂层的致密度逐渐提高,其表面质量逐渐改善。     

用电化学方法合成羟基磷灰石涂层的研究进展

简单比较了制备羟基磷灰石涂层的等离子喷涂与电化学沉积方法.概述了电化学沉积的研究进展及影响电沉积羟基磷灰石涂层形成的因素.重点阐述了电化学沉积羟基磷灰石涂层的生长机理:前驱体转变机理和直接沉积机理及其他机理.指出了电化学法制备羟基磷灰石涂层存在的问题及可能的解决方法.     

羟基磷灰石涂层材料的制备及其性能表征

设计并采用类似搪瓷涂覆的工艺制备了羟基磷灰石－Ｔｉ６Ａｌ４Ｖ复合材料．使用ＸＲＤ、ＳＥＭ对复合材料的相组成和显微结构进行分析和表征,在模拟体液中观察了获得材料的生物相容性．结果表明;在涂层中,羟基磷灰石粒子均匀地分散在玻璃基体中,它们保持原有的晶格结构,未发生相分解等现象．烧成温度对中间层玻璃涂层的显微结构有着较为明显的影响．中间层玻璃涂层与钛合金的结合强度或不小于２９．７３ＭＰａ,远高于等离子喷涂,达到使用要求．在模拟体液中浸泡一段时间后,ＸＰＳ分析表明复合材料表面有新生羟基磷灰石粒子析出,表明复合涂层有优良的生物相容性．     

电沉积法可控制备纳米羟基磷灰石涂层的研究

采用电化学沉积法在医用金属钛表面制备钙磷盐涂层,通过XRD、FT-IR和SEM表征,侧重探索电化学沉积技术在温和条件下制备结晶结构优良的纯羟基磷灰石涂层的可控性.通过控制电流密度和反应时间,即研究在恒电量条件下羟基磷灰石涂层的电化学沉积规律性,并获得电化学沉积制备纳米有序结构羟基磷灰石涂层的最佳实验条件,同时对纳米有序结构羟基磷灰石涂层的电化学沉积机理进行讨论.     

Bioactivity and mineralization of hydroxyapatite with bioglass as sintering aid and bioceramics with Na3Ca6(PO4)5 and Ca5(PO4)2SiO4 in a silicate matrix

Hydroxyapatite and Bioglass^®-45S5 were sintered together creating new ceramic compositions that yielded increased apatite deposition and osteoblast differentiation and proliferation in vitro compared to hydroxyapatite. The sintered products characterized by X-ray diffraction, revealed hydroxyapatite as the main phase when small quantities (1, 2.5 and 5 wt.%) of bioglass was added. Bioglass behaved as a sintering aid with β-TCP (Ca₃(PO₄)₂) being the minor phase. The amount of β-TCP increased with the amount of bioglass added. In compositions with larger additions of bioglass (10 and 25 wt.%), new phases with compositions of calcium phosphate silicate (Ca₅(PO₄)₂SiO₄) and sodium calcium phosphate (Na₃Ca₆(PO₄)₅) were formed respectively within amorphous silicate matrices. In vitro cell culture studies of the ceramic compositions were examined using bone marrow stromal cell (BMSC). Cell proliferation and differentiation of bone marrow stromal cells into osteoblasts were determined by Pico Green DNA assays and alkaline phosphatase (ALP) activity, respectively. All hydroxyapatite–bioglass co-sintered ceramics exhibited larger cell proliferation compared to pure hydroxyapatite samples. After 6 days in cell culture, the ceramic with Ca₅(PO₄)₃SiO₄ in a silicate matrix formed by reacting hydroxyapatite with 10 wt.% bioglass exhibited the maximum proliferation of the BMSC's. The ALP activity was found to be largest in the ceramic with Na₃Ca₆(PO₄)₅ embedded in a silicate matrix synthesized by reacting hydroxyapatite with 25 wt.% bioglass.     

磷酸盐生物玻璃粘接剂对HA植入体烧结的影响

通过在原料中添加磷酸盐玻璃粘接剂改善HA生物陶瓷的烧结性能，测定试样的线收缩率，研究了粘接剂对HA植入体烧结的影响。结果表明磷酸盐生物玻璃粘接剂能形成液相而促进材料烧结，降低烧结温度。     

Polyfunctional bioceramics based on calcium phosphate and M-type hexagonal ferrite for medical applications

Magnetic biologically active ceramics based on calcium phosphate with a content of M-type hexagonal ferrite (HF) particles varying from 10 to 50 wt % has been synthesized and characterized. It has been found that the ceramics synthesized consists of a biocompatible carbonated hydroxyapatite (CHA) with the matrix containing M-type HF particles, leading to the magnetic characteristics of the ceramics synthesized being significantly higher than those of iron-oxide-modified bioglass ceramics used in medicine.     

Microstructure and in vitro behaviour of 45S5 bioglass coatings deposited by high velocity suspension flame spraying (HVSFS)

The high-velocity suspension flame spraying technique (HVSFS) was employed in order to deposit 45S5 bioactive glass coatings onto titanium substrates, using a suspension of micron-sized glass powders dispersed in a water + isopropanol mixture as feedstock. By modifying the process parameters, five coatings with different thickness and porosity were obtained. The coatings were entirely glassy but exhibited a through-thickness microstructural gradient, as the deposition mechanisms of the glass droplets changed at every torch cycle because of the increase in the system temperature during spraying. After soaking in simulated body fluid, all of the coatings were soon covered by a layer of hydroxyapatite; furthermore, the coatings exhibited no cytotoxicity and human osteosarcoma cells could adhere and proliferate well onto their surfaces. HVSFS-deposited 45S5 bioglass coatings are therefore highly bioactive and have potentials as replacement of conventional hydroxyapatite in order to favour osseointegration of dental and prosthetic implants.     

卵磷脂对生物活性玻璃表面改性的研究

采用卵磷脂对生物活性玻璃粉体表面进行改性处理, 并研究了生物活性玻璃与卵磷脂的相互作用. 热分析(TG/DSC)、傅立叶变换红外光谱（FTIR）分析表明, 卵磷脂在生物活性玻璃表面附着,通过氢键等弱键相互作用. 表面改性后的生物活性玻璃粉体与壳聚糖复合后, 复合材料的力学强度与未处理的相比有明显提高. 扫描电子显微镜(SEM)结果显示, 经处理后的生物活性玻璃粉体在壳聚糖中分散均匀, 两者结合紧密, 表明卵磷脂改性可以有效地提高生物活性玻璃粉体与壳聚糖有机基质的界面结合强度.     

In vitro bioactivity of titanium-doped bioglass

Previous studies have suggested that incorporating relatively small quantities of titanium dioxide into bioactive glasses may result in an increase in bioactivity and hydroxyapatite formation. The present work therefore investigated the in vitro bioactivity of a titanium doped bioglass and compared the results with 45S5 bioglass. Apatite formation was evaluated for bioglass and Ti-bioglass in the presence and absence of foetal calf serum. Scanning electron microscopy (SEM) images were used to evaluate the surface development and energy dispersive X-ray measurements provided information on the elemental ratios. X-ray diffraction spectra confirmed the presence of apatite formation. Cell viability was assessed for bone marrow stromal cells under direct and indirect contact conditions and cell adhesion was assessed using SEM.     

Electrochemistry assisted reacting deposition of hydroxyapatite in porous chitosan scaffolds

Electrochemistry assisted reacting deposition method was employed to prepare porous chitosan/hydroxyapatite (CS/HA) composite scaffold with a new design device using ion exchange membranes to separate calcium salt and phosphate solutions. The results determined from XRD and SEM indicates hydroxyapatite can be electrochemically deposited in the chitosan scaffold using the device. After electrochemistry assisted reacting deposition, the surface of the chitosan scaffold was coated with low crystalline HA, particularly at the frame edge of the scaffold. The pores in the scaffold still kept interconnected well and the deposited hydroxyapatite has a cluster microsphere shape whose size is about 3-5 μm.     

Microstructure of Bioglass/Hydroxyapatite Coatings on Ti Substrate

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Microstructure of Bioglass/Hydroxynpatite Coatings on Ti Substrate

Composite coatings of bioglass and hydroxyapatite (briefly named HA/BG) with different hydroxyapatite contents on titanium substrate were successfully fabricated. The fabricated coatings are characterized by rough and poriform surface.The densities of the coatings decrease with the increase of HA content. There is a transition layer with a 5 μm thickness between the BG coating and the substrate. During heat-treatment, hydroxyapatite crystals with hexastyle shape have precipitated from the BG.