Ti6Al4V微弧氧化膜的生物相容性

采用微弧氧化(MAO)手段在Ti6Al4V表面制备TiO2陶瓷膜层,结合水热处理(HS)方法诱发膜层内生成羟基磷灰石(HA);以抗凝血性能、抗溶血性能、抗血小板黏附和材料的细胞毒性为指标,对Ti6Al4V基体合金、具有微弧氧化陶瓷膜层的Ti6Al4V合金和经水热合成处理后的Ti6Al4V微弧氧化膜层样品进行生物相容性综合评定。结果表明,经微弧氧化和水热合成处理后样品表现出优异的抗溶血性,良好的抗凝血性和血小板黏附以及无毒性,说明Ti6Al4V合金表面生成的羟基磷灰石复合薄膜赋予材料表面良好的生物相容性。     

泡沫碳化硅的生物相容性

依据国家标准GB／T16886,评价了用“高分子热解结合可控熔渗反应烧结技术”制备的泡沫碳化硅的生物相容性．结果表明：这种泡沫碳化硅没有细胞毒性,没有潜在的皮肤致敏性,遗传毒性试验、皮下和骨植入试验均未见异常反应,具有良好的生物相容性,可应用在外形复杂和长段承重骨缺损的修复．     

防粘连壳聚糖衍生物共混膜的生物学性质研究

将甲壳素、羧甲基壳聚糖和羟丙基壳聚糖按一定比例共混交联,流延成膜法制备CM-C-HP共混膜.利用细胞培养、扫描电镜、HE染色等方法对共混膜的吸水率、溶胀比、细胞相容性、细胞贴附性、皮内刺激反应、急性全身毒性、体内外降解性和生物相容性进行了评价.结果表明,该共混膜具有一定吸水率,溶胀比小,无皮内刺激反应和急性全身毒性,具有良好的细胞相容性,生物可降解性和生物相容性,对成纤维细胞的生长有较强的抑制作用,是一种极具潜力的具有良好生物安全性的可吸收防粘连膜片.     

类金刚石薄膜对纯钛的磨损保护及安全性评价

评价了以TiN为过渡层的类金刚石（DLC）复合梯度膜对齿科纯钛（TA2）的磨损防护效果以及生物安全性。采用脉冲真空多弧等离子体镀膜机,在齿科纯钛表面镀制TiN梯度膜和DLC表面膜。在体外对比检测镀膜的耐磨损能力和与纯钛的结合力,同时观察检测磨损后的表面形貌和元素分布。应用MTT法评价其生物相容性。结果表明,DLC薄膜的耐磨损能力以及与纯钛的结合力明显高于其余表面处理方法,表面形貌改变小。细胞毒性实验表明,DLC膜表面的L-929细胞增值良好。复合梯度膜的应用,可以明显提高DLC镀膜与纯钛基体的结合力。耐磨试验表明,DLC复合梯度膜可以承受日常口腔刷牙的磨耗,安全可靠,可以应用于人体。     

镁合金表面铈多层膜的抗腐蚀性及细胞相容性研究

利用旋转涂布法在镁合金表面构建了由聚乙烯亚胺(Polyethyleneimine,PEI)、明胶(Gelatin,Gel)和硝酸铈(Cerium nitrate)组成的抗腐蚀性铈多层膜.采用接触角测试仪表征了铈多层膜在镁合金表面的组装过程;利用电化学交流阻抗图谱和极化曲线研究了铈多层膜修饰的镁合金在0.14mol/L NaCl溶液中的抗腐蚀性能;以MTT和碱性磷酸酶考察了铈多层膜修饰镁合金的细胞相容性.结果表明,在镁合金表面形成了铈多层膜结构,铈多层膜表面处理提高了镁合金的抗腐蚀性能和细胞相容性.该表面处理为镁合金植入体的应用提供了新思路.     

TiN/TiCN多层调制结构薄膜的耐蚀性

多弧离子镀和磁控溅射制备薄膜各有优缺点,将2种技术复合制膜的研究还少有报道.采用多弧离子镀和磁控溅射复合技术在304不锈钢基体表面制备了TiN单层和TiN/TiCN多层膜,采用扫描电镜、X射线衍射仪并结合电化学测试等着重研究了不同调制周期下薄膜组织结构与耐腐蚀性能的变化规律.结果表明:所制备的TiN/TiCN多层膜表面平整、致密,随着调制周期的减小,TiN/TiCN多层膜发生生长取向的转变,且具有(111)晶面生长织构;TiN/TiCN多层膜在3.5 ％NaC1溶液中的抗腐蚀能力优于基体和单层TiN薄膜,随着多层膜调制周期的减小,其抗腐蚀性逐渐增强,在λ =0.150 μm时,多层膜的自腐蚀电流密度和极化电阻分别为0.106 7μA/cm2和679.700 kΩ·cm2,腐蚀速率下降到最低,具有良好的耐腐蚀性.     

铀表面非平衡磁控溅射离子镀Ti基薄膜的组织结构与腐蚀性能

金属铀的化学性质十分活泼,极易发生氧化腐蚀。本文采用磁过滤多弧离子镀在金属铀表面制备Ti过渡层,然后采用非平衡磁控溅射离子镀技术制备了Ti、TiN单层膜及Ti/TiN多层薄膜,以期改善基体的抗腐蚀性能。采用X射线衍射、极化曲线、盐雾腐蚀试验对镀层的结构、表面形貌、抗腐蚀性能进行了分析。结果表明,采用磁控溅射在金属铀表面制备一层Ti/TiN多层膜后,多层膜界面较清晰,大量的界面可终止柱状晶的生长,细化晶粒,提高镀层的致密性,有效地改善了基体的抗腐蚀性能。     

Ti/TiN纳米多层薄膜改性层在Troyde s模拟体液中的抗腐蚀性能

用电弧离子镀设备，在医用不锈钢基体上沉积Ti／TiN纳米多层薄膜，考察薄膜在Troyde’s模拟体液中的抗腐蚀性能．结果表明，在中性与酸性模拟体液中316L Ti／TiN(45／45s)体系的击穿电位分别提高5倍和2倍，腐蚀电流密度为基体的1／8与1／3，明显降低发生局部腐蚀的敏感性，但滞后环的出现说明薄膜被击穿后自修复能力较差．分析说明薄膜的纳米多层结构与纯Ti层的存在可有效提高医用不锈钢在Troyde’s模拟体液中的抗点蚀能力．     

多弧离子镀Ti(C,N)/TiN多元多层膜研究

在LF6防锈铝的基体上采用多弧离子镀技术沉积了Ti(C，N)／TiN／Ti(C，N)/TiN／TiN(C，N)／TiN六层多元多层膜，并对其组织结构与性能进行了研究。结果表明：多元多层膜表面膜层均匀，未出现龟裂现象；膜与基体之间形成了纳米级厚度的Al3Ti新相层，说明膜与基体间的结合存在化学键合，结合强度良好，划痕临界载荷达79N。显微硬度达HV0．11911．0，与基体相比，其表面显微硬度提高了近20倍，耐磨性提高了10倍以上，但摩擦因数较高(μ＝0．66)，粘着对偶件磨损，使对偶件磨损较严重。     

PLLA纳米纤维编织缝合线的制备及生物相容性研究

以PLLA为原料,采用静电纺丝和圆盘定向收集得到具有有序排列的纳米纤维束,并将其编织成线,得到PLLA纳米纤维缝合线.对新型可吸收PLLA缝线的微观形貌、血液相容性、细胞毒性进行了性能表征,并测试了其力学性能.结果表明,纳米纤维在一定的圆盘转速下表现出较好的定向性,力学性能良好.缝线在溶血试验中溶血率＜5%,符合医用材料的溶血要求.MTT实验结果表明缝线材料无细胞毒性,且显示出较高的增殖率,说明新型可吸收PLLA纳米纤维缝线具有良好的生物相容性和安全性.     

Bactericidal and biocompatible properties of TiN/Ag multilayered films by ion beam assisted deposition

Nanoscale TiN/Ag multilayered films of thickness 500 nm were synthesized on AISI317 stainless steel by ion beam assisted deposition (IBAD) with the modulation period of 4, 5, 6, 7.5, and 12 nm. The bactericidal and biocompatible properties of TiN/Ag multilayered films were investigated through Gram negative E. coli bacteria and L929 cells (mice fibroblast) as well as human umbilical vein endothelial cells (HUVEC). The results show that the TiN/Ag multilayered films with the modulation period of 7.5 nm possess the strongest bactericidal property. The cytotoxicity grade of TiN/Ag multilayered coating with the modulation periods of 7.5 nm, 12 nm is in 0-1 scope, which indicates this film has no cytotoxicity to L929. HUVEC on TiN/Ag multilayered film grows well and shows good cellularity. Auger electronic spectroscopy reveals the relationship between the structure of TiN/Ag multilayered film and the biomedical properties.     

Bactericidal and biocompatible properties of TiN/Ag multilayered films by ion beam assisted deposition

Nanoscale TiN/Ag multilayered films of thickness 500 nm were synthesized on AISI317 stainless steel by ion beam assisted deposition (IBAD) with the modulation period of 4, 5, 6, 7.5, and 12 nm. The bactericidal and biocompatible properties of TiN/Ag multilayered films were investigated through Gram negative E. coli bacteria and L929 cells (mice fibroblast) as well as human umbilical vein endothelial cells (HUVEC). The results show that the TiN/Ag multilayered films with the modulation period of 7.5 nm possess the strongest bactericidal property. The cytotoxicity grade of TiN/Ag multilayered coating with the modulation periods of 7.5 nm, 12 nm is in 0–1 scope, which indicates this film has no cytotoxicity to L929. HUVEC on TiN/Ag multilayered film grows well and shows good cellularity. Auger electronic spectroscopy reveals the relationship between the structure of TiN/Ag multilayered film and the biomedical properties.     

Nano-Ag-loaded hydroxyapatite coatings on titanium surfaces by electrochemical deposition

Hydroxyapatite (HA) coatings on titanium (Ti) substrates have attracted much attention owing to the combination of good mechanical properties of Ti and superior biocompatibility of HA. Incorporating silver (Ag) into HA coatings is an effective method to impart the coatings with antibacterial properties. However, the uniform distribution of Ag is still a challenge and Ag particles in the coatings are easy to agglomerate, which in turn affects the applications of the coatings. In this study, we employed pulsed electrochemical deposition to co-deposit HA and Ag simultaneously, which realized the uniform distribution of Ag particles in the coatings. This method was based on the use of a well-designed electrolyte containing Ag ions, calcium ions and l-cysteine, in which cysteine acted as the coordination agent to stabilize Ag ions. The antibacterial and cell culture tests were used to evaluate the antibacterial properties and biocompatibility of HA/Ag composite coatings, respectively. The results indicated the as-prepared coatings had good antibacterial properties and biocompatibility. However, an appropriate silver content should be chosen to balance the biocompatibility and antibacterial properties. Heat treatments promoted the adhesive strength and enhanced the biocompatibility without sacrificing the antibacterial properties of the HA/Ag coatings. In summary, this study provided an alternative method to prepare bioactive surfaces with bactericidal ability for biomedical devices.     

Synthesis of titanium oxide thin films containing antibacterial silver nanoparticles by a reactive magnetron co-sputtering system for application in biomedical implants

Titanium oxide thin films containing silver (Ag) nanoparticles were synthesized on commercially pure titanium (cp-Ti) substrates using a reactive magnetron co-sputtering method. The goal was to maximize bactericidal activity along with sustained biocompatibility. Furthermore, this study examined the correlation between Ag nanoparticle dispersion in the films and the antibacterial efficacy of the Ag ions released from the films. The results showed that there might be two factors affecting the inhibition of bacterial attachment to the surface of the specimens: surface morphology and Ag ion release. MTT assay results demonstrated that there was no cytotoxicity on fibroblast cells in any group. Overall, the magnetron sputtered Ag nanoparticle-containing titanium oxide coatings in this study can be used as an efficient antibacterial layer with sustained biocompatibility.     

Corrosion behavior of nanolayered TiN/NbN multilayer coatings prepared by reactive direct current magnetron sputtering process

TiN, NbN and TiN/NbN multilayer coatings were deposited on tool steel substrates using a reactive DC magnetron sputtering process. The coatings were characterized using X-ray diffraction, nanoindentation, atomic force microscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray analysis. The corrosion behavior of TiN/NbN multilayer coatings was studied in 0.5 M HCl and 0.5 M NaCl solutions using potentiodynamic polarization and compared with single layered TiN and NbN coatings. Approximately 1.5 μm thick coatings of TiN, NbN and TiN/NbN multilayers showed good corrosion protection of the tool steel substrate and multilayer coatings performed better than single layered coatings. The corrosion behavior of the multilayers improved with total number of interfaces in the coatings. In order to conclusively demonstrate the positive effect of layering, corrosion behavior of 40-layer TiN/NbN multilayers was studied at lower coating thicknesses (32–200 nm) and compared with single layer TiN coatings of similar thicknesses. The polarization data and SEM studies of these coatings indicated that the corrosion behavior improved with coating thickness and multilayers showed better corrosion resistance as compared to the single layer coatings. Other studies such as intrinsic corrosion, effects of Ti interlayer and post-deposition annealing on the corrosion behavior of the multilayer coatings are also presented in this paper. The results of this study demonstrate that nanolayered multilayers can effectively improve the corrosion behavior of transition metal nitride hard coatings.     

SiO2层晶化对TiN/SiO2纳米多层膜结构和性能的影响

采用多靶磁控溅射法制备了一系列具有不同SiO2调制层厚的TiN/SiO2纳米多层膜.利用X射线衍射、X射线能量色散谱、扫描电子显微镜、高分辨电子显微镜和微力学探针表征和研究了多层膜的生长结构和力学性能.结果表明,具有适当厚度(0.45～0.9 nm)的SiO2调制层,在溅射条件下通常为非晶态,在TiN层的模板作用下晶化并与TiN层共格外延生长,形成具有强烈(111)织构的超晶格柱状晶多层膜;与此相应,纳米多层膜产生了硬度和弹性模量异常增高的超硬效应(最高硬度达45 GPa).随着SiO2层厚度的继续增加,SiO2层转变为非晶态,阻断了多层膜的共格外延生长,使纳米多层膜形成非晶SiO2层和纳米晶TiN层的多层结构,多层膜的硬度和弹性模量逐渐下降.     

Fabrication of anticorrosive multilayer onto magnesium alloy substrates via spin-assisted layer-by-layer technique

To improve the corrosion resistance of magnesium alloy, we reported a novel approach for the fabrication of anticorrosive multilayers onto AZ91D substrates. The multilayers were composed of poly(ethylene imine) (PEI), poly(styrene sulfonate) (PSS) and 8-hydroxyquinoline (8HQ). They were deposited onto AZ91D substrates via a spin-assisted layer-by-layer (LbL) technique. The multilayered structure was stabilized with glutaraldehyde (GA) as crossing linker. It was confirmed by Fourier transform infrared spectroscopy (FT-IR). Surface morphologies and elemental compositions of the formed anticorrosive multilayers were characterized with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The corrosion performance of the multilayer coated AZ91D substrates was characterized by hydrogen evolution. The results of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements suggested that the multilayered coating improved the corrosion resistance of AZ91D substrates. In vitro study revealed that the multilayered coating was cytocompatible. The study provides a potential alternative for the fabrication of corrosion resistant magnesium alloy-based implants.     

Quantification of silver ion release,in vitro cytotoxicity and antibacterial properties of nanostuctured Ag doped TiO2 coatings on stainless steel deposited by RF magnetron sputtering

Surface treatments on biomaterials using several methods have greatly reduced the in vivo bacterial attachment, surface colonization and formation of biofilm. In this study, the effect of silver (Ag) ion release against in vitro antibacterial activity and cytotoxicity of 1–4wt% Ag doped titania (TiO₂) thin film coatings were evaluated. These coatings were deposited for 1–6 h onto stainless steel substrate (SS) using (radio frequency) RF magnetron sputtering technique. The coatings predominantly in the crystalline anatase phase were configured using X-ray Diffraction (XRD). Scanning electron microscopy (SEM) observation showed the presence of Ag–TiO₂ nanoparticles of less than 100 nm in all the coated surfaces confirming the formation of nanostructured coatings. An initial rapid release, followed by a sustained lower release of Ag ion concentration was measured between 0.45 and 122 ppb when all the coated substrates immersed in Phosphate Buffered Saline (PBS) for 1–10 days. The obtained concentration was less than the maximum toxic concentration for human cells; yet achieved antibacterial concentration, sufficient to kill or inhibit the growth of bacteria. In vitro cytotoxicity results have indicated that 1–4 wt% of Ag doped TiO₂ coatings had no adverse effect on mouse fibroblast proliferation, confirming its cytocompatibility. The antibacterial assessment was performed on 1 and 2 wt% Ag–TiO₂ coatings using Staphylococcus aureus (S. aureus) whereby significant antibacterial activity was observed in 2 wt% Ag–TiO₂ coatings.     

Hard implant coatings with antimicrobial properties

Infection of orthopaedic implants often leads to inflammation immediately after surgery and increases patient morbidity due to repetitive operations. Silver ions have been shown to combine good biocompatibility with a low risk of inducing bacterial resistance. In this study a physical vapour deposition system using both arc deposition and magnetron sputtering has been utilized to produce silver ion doped TiN coatings on Ti substrates. This biphasic system combines the advantages of silver induced bactericidity with the good mechanical properties of TiN. Crystallographic analysis by X-ray diffraction showed that silver was deposited as well in its elementary form as it was incorporated into the crystal lattice of TiN, which resulted in increasing hardness of the TiN-coatings. Elution experiments revealed a continuous release of Ag ions in phosphate buffered saline. The coatings showed significant inhibitory effects on the growth of Staphylococcus epidermidis and Staphylococcus aureus and practically no cell-toxicity in cytocompatibility tests.     

不锈钢表面含银有机硅烷偶联剂抗菌耐蚀薄膜制备和性能

通过溶胶-凝胶方法在乙烯基三甲氧基硅烷偶联剂中加入银离子,得到含银有机硅烷水解溶液,在不锈钢表面制备了抗菌、耐蚀的不锈钢抗菌膜层,研究了银离子的掺入工艺以及薄膜的抗菌性能和耐蚀性能.抗菌性能研究结果表明:银离子含量增加到3%以上时,样品的抗菌性能均增加到99.9%以上.样品经过24h去离子水的浸泡后,所有样品的抗菌性能均有所降低;银离子含量越高的样品抗菌性能保持得越好,不锈钢表面经过预氧化处理的略优于表面未经预氧化处理的薄膜.10?Cl3溶液点蚀实验测试结果表明,样品的耐腐蚀性能有明显提高,点蚀率仅为相同条件下不锈钢的1/40.